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  • HPH203 : Putting craftsmanship at the centre of your eco build – with Will Anderson

    HPH203 : Putting craftsmanship at the centre of your eco build – with Will Anderson

    Author and self-builder Will Anderson talks about realising his self-build dream not once but twice!

    Interview with Will Anderson

    Will describes himself as “a writer, actor, builder and craftsman”. His account of his first self-build was published in The Independent newspaper and is now available to buy as a book. His previous work has included writing and contributing to other publications with an environmental angle.

    A tree inspired a house with high environmental standards

    Around the year 2000, Will Anderson and his partner snapped up a rare South London plot. The very big tree it housed inspired the name and design of Tree House: a house that would work like a tree. Wanting to do their very best for that plot meant building a house that was not only wonderful to live in, but had the very best ecological performance.

    Will says any extra costs were justified by long term savings, adding, “If you built a house that had the very best environmental performance, it would also, hopefully, be the very best for you.”

    Technology helped Tree House achieve its ambitious goals

    Will was interested in the Passivhaus standard and had even contacted Wolfgang Feist, but in 2004 it wasn’t an established approach in the UK. So Will worked with his architect, Peter Smithdale of Constructive Individuals, to deliver a house that was self-sufficient in energy and “zero carbon”. To manage this meant combining a fabric first approach with “quite a lot of technology”.

    The high-performance house included a PV cell array, and a hot water panel. Furthermore, a ground source heat pump was installed in boreholes in the small plot. Will says this tried and tested technology continues to work very well, explaining, “They’re quite simple bits of technology compared to boilers.”

    Will built with the plot next door in mind

    Tree House was detached, but they knew that eventually it would become semi-detached, as there was a plot next door. Thinking ahead, Will avoided putting windows on the northern elevation that would become a party wall.

    The people who owned the garden in question appreciated the consideration and gave him first option when they decided to sell the land. He took the chance to build his second house, The Orchard.

    Where the two houses meet

    Will had to overcome issues of planning and party walls

    Building onto a detached property presented some challenges. For example, the render board had to be removed from Tree House and another timber frame wall built and filled with insulation. Furthermore the two walls couldn’t be attached (apart from some metal ties at the very top) to ensure acoustic isolation.

    Getting the right design and gaining planning permission took a long time too, but one of the biggest problems was the party wall agreement. Will advises getting a really good party wall surveyor and paying attention to the detail of the party wall award, adding, “You need to just make sure you’re properly protected.”

    The Orchard has an improved fabric but less technology

    Will wanted The Orchard to use less technology but still be very comfortable. This meant improving the fabric of the house in order to cut out the heating system. Contractors and materials were more familiar with Passivhaus principles by then and The Orchard benefitted from a purpose built external airtight layer.

    The Orchard is ventilated non-mechanically, a deliberate decision on Will’s part. He is very pleased with their Ventive passive heat recovery ventilation system, commenting, “We’ve got a completely draft free, stable interior temperature, but we still have good air quality without having all the business of mechanical ventilation.”

    Heat-recovery ventilation cowls

    Will wanted to get more hands-on second time around

    Helping finish the building of Tree House gave Will enough confidence to get more involved the second time around, although he says, “You need to know your limits, obviously”. So, even though he had done a bricklaying course, he called on an experienced bricklayer when he lost confidence on the garden wall after the tenth course of bricks.

    Some subcontractors will have their own helpers and will want to do all their work on their own terms. But Will says there are others who won’t mind you joining in. For example, given Will had some experience, the frame company, Touchwood Homes were very happy for him to lend a hand.

    The Arts and Crafts Movement inspired Will’s labour of love

    As part of the house building process, Will made his own workbench. That it has remained part of the main room says much about Will’s love of handmade items. The Orchard is inspired by the Arts and Crafts Movement and its architects, many of whose houses he has visited. What he likes so much is “the handcrafted approach, the delight in materials and in a kind of clean but very rich design.”

    Although he started without any craft skills, Will learnt a lot of trades to build The Orchard, including ceramics, even making tiles from their excavated foundations clay. To find the right course Will recommends trying out what’s local. He found one reasonably nearby in Croydon, where he learnt joinery, bricklaying and plastering. He went further afield for the more specialist skills: cabinet making in Kent and stained glass making at the Working Men’s College in North London.

    Learning skills had to be balanced with designing and building

    At the design stage, Will was already thinking about how to incorporate these crafts aspects, meaning careful planning was needed. He admits it was tricky to move between design, doing courses and starting on site and keep it all going at the same time.

    For example, the open-plan kitchen in the main living space had to be part of the overall design to make sure it would fit in: it was built long before the house! Likewise the two-storey, triple-glazed, staircase window, finished with stained glass, was always part of the design.

    Self-builders need support and patience, and to understand the industry

    Will says that self-building with no experience isn’t so hard if you get the right people to do the right jobs and you have enough patience. Understanding how the building industry works is important too. For example, Will advises being flexible rather than getting frustrated if builders don’t start when they said they would. “In the building industry, that’s absolutely standard. Not because builders are unreliable, but because people’s timetables and schedules are always shifting,” he explains.

    New technology can help with using reclaimed materials

    Will has used reclaimed materials in both houses. For example the parquet flooring uses African, Australian and Asian woods that would be impossible to source sustainably today. Modern glues can “recharge the bitumen”, so it didn’t need to be removed. This made the process easier but it was still labour intensive, especially as each room used a different wood and a different pattern.

    The blocks of wood had to be cleaned then set out properly. Will’s method was to build out from a long spine of blocks down the middle of the room. Care was needed to avoid the pattern going wonky and having to cut blocks to fit them in. Next everything was sanded down to a new surface and then oiled. Will reflects, “A massive, massive amount of work that was. But I absolutely love it.”

    Careful planning has paid off

    As the name suggests, Will wanted to build an urban orchard. He knew he wouldn’t get big machinery to the back of the house after it was built, so before he started building he replaced a lot of the poor soil with “really good quality muck”. Now the front and back gardens are densely planted with fruit trees and outside the thermal envelope are a larder and a conservatory where Will grows more tender fruit.

    As so much of the house is hand made it has been a long project, but all the work and planning was worthwhile. Will says, “We’ve taken a long time over it. But we’re going to be here forever, so that’s okay.”

    Links

    Diary of an eco-builder

     

    Transcript

    Download a transcript of the interview with Will Anderson

     

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  • HPH199 : The challenges of building close to your boundaries – with Oliver Smallman

    HPH199 : The challenges of building close to your boundaries – with Oliver Smallman

    Self-builder Oliver Smallman tells us about planning, building and living in his London Passivhaus.

    © Tim Wilcockson

    Interview with Oliver Smallman

    Oliver and his wife are not absolute beginners at self-building. They co-designed a house in Corfu where they have lived on and off for 27 years. As Oliver sums it up, “Probably not the best design I’ve ever seen in the world, but with the most remarkable view.”

    Photo courtesy of RDA (http://www.rdauk.com/)

    A rare chance to build green in London

    While the Corfu project was a tremendous experience, Oliver had no intention of self-building again. However, when he had an opportunity to buy a house in Chiswick, with an unusually large garden, he saw the chance to use new, ecological building methods to build a Passivhaus.

    © Tim Wilcockson

    The sunken design meant opting for concrete

    Oliver designed his Passivhaus with Richard Dudzicki, of RDA Architects. They originally planned to use Structural Insulated Panels but the site was very constrained and Richard saw the potential for sinking the house below ground. Thus they chose a piled site and a concrete build.

    Oliver had already fallen in love with the use of boarded concrete and explains, “The concrete walls on the interior, boarded and plain and smooth, were always in the plan.” The mixture of textures is part of what Oliver calls, “concrete as a look”; they even allowed the errors of the pouring to remain.

    © Tim Wilcockson

    The brief called for concrete, convenience and light

    As well as using concrete, Oliver wanted to avoid the house being dark. He says lots of glazing along the south of the house works well for a Passivhaus.

    In terms of style, he had grown used to travelling in his work life and Oliver appreciates functional touches like having the lights over your bed and the switch at hand. “It’s a little bit “hotel-y” but it really suits me,” he says.

    © Tim Wilcockson

    Neighbours objected to the modern design

    Although the planning application was recommended for approval, about 40 local residents came to the planning meeting with extremely negative reactions and three councillors stopped the application.

    One reason given was excessive size, despite the majority of the house being underground. They also argued the house was not “in keeping with the area” but Oliver has a different perspective, asking, “Why would you build a replica of a house that was built in 1949 or 1950? You’d be mad!”

    © Tim Wilcockson

    Repeated planning applications didn’t just pay lip service

    Rather than sacrifice his contemporary design, Oliver tried to absorb feedback to gain his neighbours’ support. This meant some meaningful compromises where the design was blended in. For example, Oliver chose to match the white exterior walls and bricks of the other houses in the road.

    A smaller second design allowed more green space, but the application was rejected again. Oliver then lost his appeal on the grounds that he wasn’t providing parking. Further reducing the top floor enabled off-street parking to be included in the next application.

    © Tim Wilcockson

    Getting planning consent took four applications

    Having seen the application a number of times, twelve Council members gave up their Saturday morning to come and look at the site. The opposition party made representations but Oliver says they made the mistake of behaving rudely. As he explains, “I think the Council officers probably thought, ‘You lot are nuts and this guy’s doing something perfectly reasonable.’”

    At the next vote, the same three councillors objected, but the others disagreed, so planning permission was finally granted four years into the process. Oliver notes that the final design fits the street and has become accepted. The modern house is softened by use of greenery and locally appropriate materials.

    © Tim Wilcockson

    Research led to the right concrete and windows

    Although Oliver was inspired by the use of concrete in stations like Westminster, his design contrasts it with wooden floors. In addition, he used Portland Whitener to lighten the colour. Oliver went to the Concrete Centre and signed up for the course in concrete pouring. “You can’t just phone up a concrete company and they bring you concrete and pour it and then it looks like this,” he says.

    Oliver also did a lot of research to find the right triple-glazed windows. He has been happy with the certified Passivhaus windows and service provided by Internorm.

    © Tim Wilcockson

    A tight urban site presented challenges

    The eight by eighteen metre site meant building close to boundary walls. The existing house had to be underpinned and Oliver needed to protect his neighbour’s house and cherry tree while digging a four-metre hole within three metres of them. To give Oliver the security to start digging out, a specialist company was used to sink the concrete piles.

    Digging a large hole on such a tight site meant that space for storage and machinery was permanently on the move. As Oliver says, “It’s like a dance. When we were piling it, the piler would be in one corner, the concrete machine would have to be in another one.” They even built a platform to put the digger on to remove the last piece of soil.

     

    © Tim Wilcockson

    The Passivhaus offers comfortable, healthy living

    When the house was complete, Oliver actually rented it out for a while. Staying in his existing draughty house meant he appreciated the difference even more when he moved in. Three things surprised him. Firstly, how quiet the concrete-built, triple-glazed house is. Secondly, the fantastic air quality and thirdly, living draught free, with the same temperature everywhere.

    Oliver isn’t dogmatic about the Passivhaus method but is extremely satisfied. “There may well be better solutions in the future, but I’ve now had the opportunity to live in this house for nearly a year and I absolutely love it,” he says.

    © Tim Wilcockson

    Leaving a legacy costs more

    Oliver’s house is designed to last and be efficient. As he explains, “I’m trying to build something that uses very little power and little energy, and I’ll be long gone but it’ll be a very valuable asset either for my own children or for somebody else.” In fact, he says his energy costs are easily under £500 a year.

    However, Oliver admits the build cost more than he’d intended, saying, “I thought I could do it for £400,000 and I built it for £600,000 finished.” Digging out the soil had been much more expensive due to bad weather. Moreover, he could have saved on some specifications but paid more for feel and durability. For example, he fell in love with the floor in the Saatchi Gallery. He reveals it cost “a crazy amount of money” but the untreated Douglas Fir will last hundreds of years and could be sanded a thousand times.

    © Tim Wilcockson

    Oliver’s tips for self-builders

    Commercial builders tend to avoid low energy builds as they are less profitable, but Oliver remarks that the more people who put up good buildings, the more the country as a whole will benefit.

    His key advice is to persevere. As well as using Google for research, he has two other top tips for green builders:

    Find out more

    UK Passivhaus Awards 2016

    RDA Architects

     

    Watch a video on Chiswick Eco Lodge

    Transcript

    Download a transcript of the interview with Oliver Smallman

    Please connect with me

  • HPH198 : Creating an interior that works perfectly with the exterior – with Emily Bizley

    HPH198 : Creating an interior that works perfectly with the exterior – with Emily Bizley

    Interior designer Emily Bizley explains how she and her husband, an architect, co-designed their RIBA shortlisted self-build home.

    Interview with Emily Bizley

    Emily wanted to be an interior designer since she was very small, but ended up studying French and Psychology at university before deciding to go to Chelsea Art College to pursue her childhood dream. After gaining more qualifications, Emily worked for architects to get some experience. From there she went to work for an interior designer in London, and now has her own practice based in Somerset.

    The interior shouldn’t be an afterthought

    If design decisions aren’t guided by “a bigger idea about what the building is supposed to be”, there’s a risk that the interior and exterior won’t be coherent. Emily explains they wanted to build a timber house that was sympathetic to and connected with the surrounding countryside and nearby agricultural buildings.

    She says she’s visited a lot of timber clad houses that look fabulous on the outside but whose interiors are “a crashing disappointment because it’s all white plasterboard with twinkly down lighters and absolutely no atmosphere.” She finds it surprising these houses aren’t made of wood both inside and out, like those she and her husband visited in Switzerland.

    Ask yourself how you want each room to feel

    Emily and her husband both did a lot of sketching for their self-build. They focused much more on how they wanted a room to feel, rather than how it would look. Sketches of room scenes helped them imagine their lives in the new house and captured the desired atmosphere.

    Design the interior and exterior in partnership with one another

    Focusing on how they wanted the kitchen to feel took them through a series of questions; the answers defined the design inside and out. For example, thinking about what they wanted to look at while eating breakfast, and where the sun would be coming in, suggested the size and position of the windows. But then they had to consider how this would affect the elevation outside, and the design needed tweaking to get to the point where it worked inside and out.

    Emily says they decided to have their sitting room separate to (but adjoining) the open plan kitchen dining area. They designed this room to be a half level up with the ceiling following the roofline down, making it a cosy snug. She explains the materials they used are the same, it’s just that the space has been slightly manipulated to create a different atmosphere.

    Think about how natural light will reach all the spaces

    Emily’s house has light from all sides. She says it is really important to ensure that the darkest parts of the house still get natural light. They incorporated skylights into the design for their self-build, to avoid any “dark dingy corners”.

    Create interesting relationships between spaces, inside and out

    The sloping site presented challenges. Emily explains, “A developer house would just be plonked on stilts at the front to make the site flat, but then you lose the relationship to the garden”, adding, “We didn’t want that feeling of being on the upper floor and feeling really disconnected from the garden.” Instead, they dug down to enable the house to sit back in the hillside and decided to go for an upside down layout, taking care to create access to the garden from different places.

    Their self-build uses internal glazing to create interesting relationships within the house – the rooms aren’t “a series of boxes with doors”. Emily says that internal glazing was something she and her husband had always liked about French houses and had been on their list of things they’d wanted to incorporate into their designs.

    Be generous with some spaces to create the right atmosphere

    Sometimes it’s worth sacrificing a bit of space to be generous elsewhere. In the case of Emily’s self-build, the design for the lower floor incorporated a wider hallway. She doesn’t see this as wasted space as it avoids the feeling of going downstairs into a rabbit warren of bedrooms.

    Restrict the palette to avoid a “mishmash of everything”

    There are a lot of options when it comes to interior finishes. Emily says they were quite disciplined in having just a few ideas for their interior and carrying those through with some rigour. She describes the house as having “two quite distinct overall sorts of atmosphere”. The rooms are either lined with oak or painted plywood; no walls are just plastered. And some of the ceilings are crafted from rough-sawn softwood and painted.

    A joiner made their bespoke kitchen and he sourced the wood from the same supplier used for oak lining the walls. Emily comments, “The kitchen is intended to look like the walls, and blend in.”

    Think about furniture early on as it impacts the design

    Although Emily believes it’s good to let ideas develop and to be able to respond in an organic way, it’s also important to have an overall idea when it comes to furniture. She uses their veranda as an example, explaining that it is pretty much square in plan, but as the house is not a square box the corner of the deck intentionally gets wider to accommodate the table and chairs.

    It also helps to know what you’re planning to do furniture-wise to produce electrical plans. For example, do you want to sit in a particular well-lit corner and read? The position of an extractor fan in the kitchen is another important consideration – what type of cooking do you tend to do, and does that require extraction directly above the hob?

    Factor in storage during the design stage

    Emily comments, “If we did decide to put everything away, there would be a space for everything.” The big store at the back houses the plant, store and utility rooms. They also incorporated really big wardrobes into the kids’ bedrooms and Emily and her husband have a lot of storage space in their dressing room.

    Other tips for self-builders

    • Collate images of anything you really like into a folder
    • Have some clear ideas and follow them through – don’t get distracted
    • Think about how materials and texture can achieve the atmosphere you want 

    Watch a 2-minute video about their home

    Find out more

    Visit the website of Emily Bizley Interior Design

    Follow Emily Bizley on Instagram

    Visit the website of Prewitt Bizley Architects

    Transcript

    Download a transcript of the interview with Emily Bizley

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    Follow Ben Adam-Smith on Bluesky

  • HPH197 : Taking risks, overcoming challenges and achieving outstanding results – with Jon Martin

    HPH197 : Taking risks, overcoming challenges and achieving outstanding results – with Jon Martin

    Jon Martin explains how he beat the odds with his extraordinary self-build tree house.

    Photo courtesy of Grand Designs Magazine

    Interview with Jon Martin

    Plumber Jon Martin and ceramicist Noreen Jaafar sold their high-maintenance Edwardian house to fulfil their dream of building their own home: an architecturally innovative Passivhaus that preserves the ecology of its urban plot.

    All house photos by Tomas Millar of Millar + Howard Workshop

    Local knowledge helped Jon find an urban plot

    Jon has always liked living in the town centre. He wanted to keep his fuel and energy costs and carbon footprint to a minimum. Urban plots are usually hard to come by but they managed to find one within nine months.

    Once the large, formally planted garden of a bank manager, the plot was sold off by the Royal Bank of Scotland. Although considered an eyesore locally, the plot had 28 listed trees and a rich ecology, and various planning applications had been turned down.

    Jon explained to the neighbours and council that he wanted to preserve what was there, not just “come in and butcher the area”. As a local, he thinks he may have been more readily trusted, saying, “I don’t think it had any sway but I didn’t get the resistance that I think somebody from outside might.”

    The need for surveys and outstanding design increased cost

    Jon and Noreen knew that gaining planning permission rested on their design adding outstanding architectural value to the surrounding area. Outline drawings cost a fair amount and an outstanding architect costs even more.

    In addition, they needed to reassure the planners that existing ecology, arboriculture and even archaeology could be protected. There was abundant wildlife, including bats, badgers and slow worms. Jon says, “The only thing we don’t have is a great crested newt!” Specialists were needed to establish what was present and prove it could be preserved.

    Buying without planning permission was a big risk

    Although the house hasn’t been valued, Jon believes that the plot economics have worked out. However, he probably wouldn’t take such a risk again, saying, “We bought it without planning permission, actually having been told by the local Council we wouldn’t get planning permission.”

    The plot cost £85,000 and its restrictions meant spending nearly £20,000 on surveys, meaning that the couple had borrowed £105,000 before getting planning permission. Considering their limited budget, Jon says, “It was either a very reasonably priced building plot or an incredibly expensive garden!”

    Local support and detailed designs helped their appeal

    Despite having unequivocal support from the neighbouring church and the Parish Council, the planning application was turned down. The only option was to go to appeal at the district Council. Jon went armed with a scale model showing every tree.

    The appeal went through unanimously with the application cited as an exemplar of how to enhance a town centre. They have also been given a Campaign for the Protection of Rural England award. Jon says it is rare for a house to be recognised like this but with no concrete used throughout the build, it actually “treads very lightly”.

    The design was challenging and contractors got cold feet

    Finding the right professionals wasn’t straightforward. The structural engineer needed to work with a design delicately raising cantilevered sections into the air on slender legs, surrounded by trees. Planning how the 16 piles would miss tree roots took trial and error, digging small excavation holes and where roots were found, repositioning the pile and recalculating.

    Unfortunately the first contractor they gave a deposit to went bankrupt. Moreover, Jon says that some contractors were put off by the project appearing on Grand Designs. A second contractor tendered for the contract but then got nervous and wanted to raise their price. About three years in, with only a few screw piles in the ground, Jon realised he had to take over as the main contractor.

    Building a Passivhaus provided a standard to meet

    The Passivhaus standard dictated levels for air quality, MVHR noise, duct size, energy use and temperature range. Jon says the cost of an energy consultant paid off in comfort, adding, “On a sunny day, it really does heat itself, it’s incredibly pleasant to live in.”

    The Passivhaus ‘form factor’ determined how other aspects of design had to offset the shape of the building. Jon and Noreen’s house has quite a large surface area compared to volume and Jon says, “Everything has to be proportionally better to come in under the Passivhaus benchmark.”

    Innovations in the structure and insulation benefitted the house

    The house is free from thermal bridges, achieved by a “twin skin” containing 400mm of insulation. Using open-celled spray foam insulation improved airtightness and reduced off-gassing. Jon says it is nearly impossible to get the airtightness required for a Passivhaus using slabs of insulation. With spray foam and a lot of design and taping he achieved an exceptional airtightness.

    The open-celled structure of the foam meant that off-gassing finished within two days whereas Jon says formaldehyde can come out of conventional slabs of insulation for decades. Although more of the open-celled material is needed, it breathes and is airtight and so he says it is hard to beat.

    The house was 90% built by two people in 18 months

    Jon thinks it took about 18 months of building for him and another man, with occasional help from a plasterer, an electrician and one additional man. Jon’s huge DIY effort included plumbing, putting the roof on, hauling and cutting all the timber and putting up the floors, walls and tonnes of steel.

    Although the house wasn’t completely finished when they moved in, another six months saw the bedrooms and stud walls finished off.

    Jon’s tips to keep it simple and love your build

    Jon admits that he actually hated the build process at times. They even fell ill during the difficult planning process. “Unfortunately it really does rip your soul out,” he says. Now that he is settled into the building, however, he absolutely loves it.

    House building is challenging and Jon would try to enjoy it more if he did it again. To achieve this, and come in on budget, his advice is to simplify:

    • Choose a simple design
    • Invest where it pays dividends: the fabric of the building, the insulation and the windows.
    • Save on areas you can upgrade later: the kitchen, carpets or floor material
    • Cut costs early and be honest with yourself. The buck stops with you, so make changes sooner rather than later, whether relating to contractors, materials, or unforeseen circumstances.

    Find out more

    Visit the website of Dursley Tree House

    Sign up for Jon and Noreen’s newsletter

    Transcript

    Download a transcript of the interview with Jon Martin

    Please connect with me

  • HPH195 : What is cellulose insulation? – with Gordon Lewis

    HPH195 : What is cellulose insulation? – with Gordon Lewis

    Gordon Lewis explains what cellulose insulation is, how it’s applied and why self-builders can benefit from choosing it.

    Interview with Gordon Lewis

    Gordon Lewis has been involved with cellulose insulation for over 26 years. He mainly works installing Warmcel insulation into timber-framed properties.

    Choosing insulation material is important

    Cellulose became known as an insulation product in the early 1980s. Made from recycled newspaper, it is a highly sustainable product. The newspaper is milled down to make the fibres much smaller, then fire-retardants are added.

    Gordon admits that man-made insulation materials are likely to continue in the market but he is optimistic about the alternatives, saying, “Cellulose is slowly creeping back into the marketplace and doing a great job.”

    Paper use has declined but cellulose insulation is still available

    The growth in information technology has meant a decline in the availability of newspaper for recycling. Along with overhead costs, this has resulted in some factories closing. For example, Gordon’s former employer, Excel, the sole UK manufacturer of cellulose insulation, closed down in 2014.

    Sources of newspaper and cellulose insulation do still exist, however. There is one company in Ireland and there are many more manufacturers of cellulose on the continent. Gordon uses a brand called Warmcel, which is made by CIUR in the Czech Republic and shipped to the UK.

    Any timber-framed building can incorporate cellulose insulation

    Cellulose can be used for other build methods, but is ideally suited to timber frame buildings. Because it’s made from paper, it must be fitted in a way that avoids contact with any damp surfaces. There are a number of different materials that can make the “sandwich” containing the insulation; it might be rigid board on both sides, or one side could be a membrane.

    Different boards also have different thermal performances, so it is worth thoroughly researching all the materials involved. This includes speaking to people that have had properties built, architects, builders, or the installers. Gordon says, “Ask as many questions as you possibly can to get on the right foot, to say, ‘that’s the product that I need.’”

    Cost and quantity of insulation are based on location, depth and density

    In order to calculate cost and how much product is needed, Gordon considers where the cellulose insulation’s going, the depth of the space to be filled and the density required. Locations could include internal or external walls, floors, an attic space or a sloping ceiling. Gordon uses formulae to establish how much material is required for that particular build.

    Any moisture issues must be addressed prior to installation

    Generally, before any installation is carried out with cellulose, the building needs to be wind and watertight. Cellulose will dry up and cope with a certain amount of moisture, but not too much. For example a constant leak or rainwater continually getting in to the frame would cause problems. If the doors and windows are not in, those access areas can be masked off with polythene on both sides to stop rain being driven in. Gordon will look out for water or staining on boards from rainwater that may have dried up over a day or two. To inspect for damp before installing cellulose he might drill the wall and test by hand.

    Holes in the wall allow the insulation to be pumped in

    The cellulose needs to fill voids created by the timber frames and rigid boards, and there can be hundreds of them to find. Experience gives Gordon familiarity with typical frame kits so he knows the small gaps to watch out for, and how to access them. He can also identify them from the screw patterns, looking at the drawings, speaking to whoever fitted the boards, or even asking them to mark the boards showing whether or not there’s a gap. If there’s still any doubt, he may drill a small hole to check.

    Special sealing tape is used to maintain airtightness afterwards

    Once a hole has been cut to access each void, and the insulation pumped in, the core is sealed back over the board. To make it 100% airtight, the tape must have no creases. On the job where Gordon and Ben met, the PH15 build had close to 500 holes cut and repaired. The airtightness test showed below 0.01 air changes an hour at 50 Pascal; one of the best results recorded.

    After installation, moisture problems are rare and can be rectified

    In Gordon’s experience, once the insulation’s in, it’s there for the lifetime of the building. He comments, “As long as the fabric and the structure of the building is sound, it’ll be there forever and a day.” He has had few subsequent issues, maybe three or four over 26 years. He believes those failures arose because people didn’t understand the building needed to be wind and watertight.

    If mismanagement does result in a bad leak going into the insulation, it can be replaced once the building is watertight. Gordon explains, “We have to cut a large hole in the board, if it’s not too badly damaged, or the whole board is taken off, and then all that wet insulation is totally removed before it can be replaced.”

    Experience counts but self-builders can get involved

    While Gordon has a lot of expertise in his field he encourages keen self-builders to get involved, saying, “They can get to the point where they can actually install the insulation themselves, if they want.”

    When he’s been on jobs where self-builders have helped, Gordon has supervised everything and made sure the equipment is set up right. Gordon uses a Krendl machine that breaks up the fibre, and then blows it from an airlock through the hose to the delivery point. Knowing that each cavity is full enough is mostly down to experience, but there are tests to check the density and location.

    Cellulose insulation is gaining popularity

    Gordon sees a growth in using cellulose insulation in line with a wider increase in green building techniques. More people are demanding greener products and want the benefits of Warmcel or another cellulose product.

    He sees the market increasing slowly, saying, “People are looking to recycle as much as they possibly can. Whether it be the insulation, the boards, all sorts of things, and sourcing the material as locally as possible.”

     

    Find out more

    Visit the website of CIUR

    Transcript

    Download a transcript of the interview with Gordon Lewis

    Why the location of a self build is an eco consideration

    Ben Adam-Smith reflects on one aspect of his last house that he absolutely loved: its location. It was close to local amenities, and meant that Ben did a lot more walking and only needed one car for the whole family!

    Please connect with me

  • HPH193 : Should you specify uPVC windows? – with Simon Corbey from ASBP

    HPH193 : Should you specify uPVC windows? – with Simon Corbey from ASBP

    Simon Corbey from ASBP shares some of his research into the costs and life cycle of plastic windows and suggests some considerations for self-builders.

    Interview with Simon Corbey

    Simon Corbey worked as a chartered surveyor in the ‘90s, and went on to become a specialist in natural paints for London’s first eco builders’ merchant, Construction Resources. He has also worked for BioRegional, the Sustainable Development Foundation, the Good Homes Alliance and the Alliance for Sustainable Building Products (ASBP). Last time we spoke to Simon, he talked to us about healthy building products.

    We should question the chemicals in uPVC

    Simon Corbey has been working on behalf of the ASBP to compare plastic and timber windows. Consumers tend to be more concerned with how windows will look and last than where plastic comes from and the issues around it. Simon remarks that plastic windows are manufactured widely in the UK, but these impacts are not really considered, adding, “I do think that there’s an opportunity for the UK to develop their building physics and approaches to making windows.”

    Simon notes that plastic windows appeal, as they are generally cheaper and available in a range of styles. He describes the marketing as aggressive, adding, “It’s well funded, of course. It’s the petrochemical industry.” Plastic windows contain a range of chemicals but no research has suggested a negative effect on indoor air quality. The window itself may be benign, but Simon has also been researching product manufacture and life cycle.

    Manufacturing chlorine is hugely energy intensive

    Simon explains that uPVC (unplasticized polyvinyl chloride) contains chlorine. Used in swimming pools and our water supply, it’s common enough to not raise concern. However, he explains that its manufacture has an incredible impact on the environment.

    Simon estimates that producing 80% of the UK’s chlorine uses more electricity than Liverpool. Production of PVC in Europe in 2015 used 8.6 million tonnes of chlorine. “So it’s hugely energy intensive,” says Simon, adding, “From a life cycle analysis it’s a terrible, terrible thing.”

    Simon’s research shows the hidden costs of uPVC windows

    Simon has further researched Ineos, who produce most of the UK’s chlorine. Describing it as “a very murky world,” he says he feels motivated to bring this to people’s attention. The site of the Ineos plant in Cheshire is of particular concern. Simon describes how Ineos were caught dumping mercury into the Manchester Ship Canal in 2014 and the land contains a dump once used to “make everything from nuclear weapons to World War II stuff”.

    Previously owned by ICI, the dump was linked to toxic chemical leaching and reports of ill health in the early 2000s. Today, explains Simon, if you look at the Land Registry, this dump apparently has no owner. “There is a completely toxic dump just there which the council don’t own,” he says. “Ineos have somehow redrawn the lines of their site and conveniently they don’t own it any longer.”

    Timber windows struggle to compete on price and marketing

    Despite their significant environmental price, plastic windows remain cost effective for manufacturers. The price of oil and gas is still low, making the raw materials cheap. The process of gathering timber, processing, sawing and milling it is quite energy intensive in comparison and the end product is heavier to transport. All of this adds to cost.

    Simon further points out that the UK timber industry is quite fragmented, containing many different disparate interests. Conversely the plastics industry markets products with “one voice”, typified by slick campaigns, such as that for Everest windows. Moreover, Simon describes it as quite litigious, recalling a threat of court action when his former employer persuaded a Scottish Housing Association to cancel their order for plastic windows.

    Plastic windows may not outlast timber

    There is a perception that timber windows will rot, requiring repeated maintenance, while plastic is assumed to be tougher. Simon questions these preconceptions. While acknowledging that timber windows have a finite life cycle he points out that plastic windows are prone to yellowing after a while. Simon himself has 120-year-old timber windows, which are “going strong”. “They’re a bit leaky,” he says, “but they’re okay as far as I’m concerned.”

    Other options for window materials do exist. Simon recommends considering factors such as product life cycle and building location. Aluminium is very durable but highly energy intensive; composite timber and aluminium windows are one alternative.

    The quality of UK timber windows is improving

    Windows are an essential part of the building fabric’s performance. With improvements in building science, double glazed and triple glazed windows are appropriate for new builds and both plastic and timber windows can achieve Passivhaus Trust certification.

    Where good indoor air quality is maintained by natural ventilation, windows must function well, being easy to open and clean. There have been some issues of quality with some timber windows but Simon sees this improving, following the standard of European and Scandinavian manufacturers.

    Recycling plastic windows involves additional expense, chemicals and risks

    The Scottish Civic Trust suggests that the recycling rate for windows might be 3% and according to the Green Guide, BRE suggest that the UK average is about 15%. However, Simon suggests the many issues with recycling, such as the chemicals and risks involved, make that figure optimistic.

    The formulation of plastic has changed quite a lot since the ‘60s and the industry has made great attempts to clean itself up. Substances considered by REACH to be of very high concern, such as lead and cadmium, are being phased out although tiny quantities are still allowed.

    Plastic is worse than wooden windows in a fire

    Simon believes that toxicity is a huge issue. He confirms that plastic windows pose a greater risk than wooden ones in the event of a fire and believes that more research is needed. However, currently all the testing institutes are very busy “as a result of Grenfell”.

    Simon notes that in the USA, The Healthy Building Network has liaised with the Fire & Safety community to argue for a complete halt to use of plastic products. Likewise, the ASBP has initiated contact with Kent Fire and Rescue and the London Fire Brigade. As Simon explains, “there is some research underway but it’s early doors, I would suggest, this type of testing.”

    Industry and consumers are moving away from plastic

    Techniques and attitudes continue to change. Acetylated wood is an example where window science has improved. This process basically uses vinegar to extend the maintenance life of timber to over 60 years.

    Simon notes a growing interest in health and wellbeing, as well as a global campaign against plastics. He summarises, “I think at ASBP we’re trying to suggest that as a society we’ve just got to start using less plastic through and through, in all the things that we do and windows being one of those things.”

    Find out more

    Visit the website of the Alliance for Sustainable Building Products (ASBP)

    Follow the ASBP on Bluesky 

    Transcript

    Download a transcript of the interview with Simon Corbey

    Please connect with us

    Subscribe, rate and review us on Apple Podcasts

    Like our Facebook page

    Follow Ben Adam-Smith on Bluesky

  • HPH191 : Key decisions that impact on the sustainability of a house build – with Lloyd Alter from TreeHugger

    HPH191 : Key decisions that impact on the sustainability of a house build – with Lloyd Alter from TreeHugger

    Lloyd Alter from TreeHugger shares his advice on what we should be prioritising as 21st century self-builders.

    Interview with Lloyd Alter

    We catch up again with Lloyd Alter, whose work as an architect and a real estate developer led to his interest in modern building methods. He blogs for the website TreeHugger and also teaches sustainable design at Ryerson University in Toronto, Canada. Previously, Lloyd’s talked to us about worldwide trends in green designs.

    Don’t measure value in pounds per square foot

    Lloyd says that size will be the most important decision about a house build because so much relates to it. While building small may be preferable for sustainability, he acknowledges there are various problems to overcome.

    Some contractors may refuse work on smaller houses, or argue that a bigger house is better value. Lloyd warns against buying more space than you need. A bigger house may cost less per square foot but that is a dangerous criterion for measuring value. He explains, “It will cost you more per unit of area to build smaller but the aggregate, it will still cost you less.” Operating and maintenance costs will also be less with a smaller dwelling.

    House size may be dictated by the plot

    Re-sale value can force a self-builder into a larger project. Often it’s the land that really has the value, so there’s a judgement to be made about the right sized house for the size of the plot. And Lloyd points out that putting in services costs the same regardless of house size, potentially making it harder to recoup costs on a smaller house.

    By-laws can, in some instances, prevent small homes being built. For example, Lloyd explains that some North American municipalities fix minimum square footages to guarantee a minimum tax return.

    Balance location with lifestyle

    Lloyd recognises the dilemma for self-builders who want to minimise their carbon footprint but can’t afford the expensive land located close to facilities.

    Low energy buildings can reduce environmental impact, and changing habits can also mitigate high-energy consumption. Someone Lloyd knows – who lives 9km away from town – cycles, uses a hybrid car when he has to drive, minimises shopping trips and avoids ordering things delivered by truck. Lloyd himself tries to balance his many air miles by cycling and keeping his house at “incredibly low temperatures”.

    An independent expert will help you design for sustainability

    In a poorly planned house, you pay more for a poor living experience. Lloyd mentions one self-builder who incorrectly fitted insulation and this decision threatened to destroy his house.

    For Lloyd, an architect should “help you get to the essentials and put the essentials together in the most efficient, satisfying and beautiful way.” He sees this as directly linked to building sustainably: “The key to sustainability is living with less and the key to living with less is to have it designed properly.”

    To choose an architect or builder, Lloyd suggests going to see their work and spending enough time with them to know that you like them, they understand you and that you can understand what they’re saying; clients shouldn’t have to deal with what he calls “Architectese”!

    Simplicity should be designed into the house in the first place

    So-called “smart homes” are fashionable but Lloyd is wary of unnecessary complexity that adds cost and needs maintenance. “My attitude is I like a dumb home!”, he says, citing the Passivhaus as a good example of this. Using less power means no need for a smart thermostat or a complicated solar panel system connected to the grid. “The house takes care of itself,” he says.

    Another reason to keep house design simple is to accommodate changing technology. Low voltage LED bulbs have practically eliminated the problem of lighting load and our technology increasingly runs on low voltage DC wiring. Lloyd envisages future houses solely using DC, so any high voltage electric systems fitted now should be kept accessible.

    As different building elements last different lengths of time, Lloyd’s advice is to prepare and keep things simple. “Put as little of it as you need in. Because at some point, you’re going to have to redo it anyway.” Homeowners should be able to access, change or fix any systems in the house:

    Element of your propertyHow long it may last
    LandForever
    Frame of your house500 years
    Cladding200 years
    Windows100 years
    Plumbing50 years
    Electrical20 years
    Mechanical systems10 years

    Fabric first is fairer as well as simpler

    Lloyd believes it is unreasonable to simply aim for “net zero carbon”, stating, “We have to use less, period. Even if we’re trying to offset it with energy from sun or wind.” Thus, investment in domestic energy production is another trend that Lloyd mistrusts. Compared to the huge amount of energy used for transport, he describes solar panels on roofs as inconsequential. “We should be going after the big things. And that’s efficiency, not solar panels on the roofs,” he says.

    He remarks that policies of domestic generation of electricity disproportionately favour people who have south-facing roofs. Someone without a roof or who can’t afford solar panels will pay more for their electricity, meaning the poor end up paying for the grid. A fairer system in Lloyd’s view would be for everyone to live in houses that are built to a higher standard and use less energy.

    Preferred methods of building continue to change

    Lloyd teaches a sustainable design course and the content can change every year. Ten years ago, he taught about spray foam that seals and insulates efficiently, but we know now this foam contains unhealthy flame-retardants and some don’t even work below three degrees Celsius. The current insulation trend is for low carbon cellulose, although Lloyd prefers rockwool.

    On the subject of new building techniques, Lloyd says, “I’ve become very conservative as I’ve gotten older.” He sees people who want the “latest new thing” demolishing existing houses on highly sought-after plots. This discourages building really good quality houses because “they don’t seem to be building them forever anymore”.

    Construction methods can be more suited to specific locations

    Building with “brick and block” gives thermal mass, holding heat in the day and releasing it at night. Lloyd says that this principle works well in the high Arizona desert, with hot days and cold nights. In less extreme climates such as the UK it is less effective, and making bricks, concrete and mortar releases a lot of carbon dioxide before construction even begins.

    Homes should be comfortable, safe, secure and resilient

    A self-build should bring comfort and happiness. Just because it’s environmentally friendly doesn’t mean you have to suffer!

    Considering our changing world, Lloyd advises self-builders to prepare for power outages, provide some storage for water and food, and build high enough and not in the middle of a flood plain. He adds that if you have to cycle to get milk, then make sure you can actually do it! “That’s what a home is supposed to be,” he says. “A place of security and comfort. That’s what we should all be striving for.”

    Find out more

    Visit the website of TreeHugger

    Follow Lloyd Alter on Twitter

     

    Transcript

    Download a transcript of the interview with Lloyd Alter

    Please connect with me

  • HPH187 : What keeps a self-builder awake at night? – with Will Kirkman from Ecomerchant

    HPH187 : What keeps a self-builder awake at night? – with Will Kirkman from Ecomerchant

    Will Kirkman from Ecomerchant shares the key results of a survey the company ran to find out what self-builders worry about most.

    Interview with Will Kirkman

    Will didn’t actually get a PAYE job until his 40s. Assorted pursuits over the years, including farming and metalwork, eventually led him to civil engineering. He now runs Ecomerchant, a sustainable building materials supplier.

    Will says that self-building is a unique and new experience for most people who do it, so there can be a lot of uncertainty along the way.

    In an effort to find out a little bit more about the market, the company surveyed customers and identified the top five worries.

    1. How much should my project really cost?

    Total build cost is made up of many components. It can be hard to work out what proportion of the total should be on various upfront fees and professional services versus the construction itself, let alone establish actual costs. As dreams become reality, controlling costs can also prove tricky causing anxiety levels to rise.

    Will acknowledges that there is a sliding scale depending on how ‘standard’ the build is and how hands-on a self-builder plans to be, but suggests an indicative cost of between £1200 and £1800 per square metre.

    When it comes to build cost, trusting the professionals is important. Will suggests the core three team members would ideally be client, architect and builder, and recommends engaging with the building materials supplier as soon as possible.

    Will says there are ways to prevent the budget being blown by unforeseen problems. If a builder is doing something for the first time, the quote is likely to take into account this increased risk. So it is wise to choose an architect and builder that is experienced with your preferred build system.

    2. Am I getting good value and good quality?

    Will says, “I think this is about being sensible about what your expectations are and also understanding what people’s skillsets are.”

    He argues it is reasonable to want a house to perform in the long term and therefore expect it be built to a high standard. Unlike the volume housing market, self-builders are in more control of this; but success relies on the entire build team sharing a common understanding of what they’re trying to achieve.

    Will recognises that people can be tempted by short-term savings, especially if their project is going over budget. However, these savings will often cost more in the long run; some examples include:

    • A relatively inexpensive paint can peel off or fail in other ways;
    • Plastic baths will always move, leading to gaps along the silicone, and possibly leaks and damage;
    • Internal doors contribute massively to the acoustics of a building and cheap ones won’t insulate noise well.

    Aesthetics can also distract from a product’s core function. Will reminds us that “value and quality are different things to taste.” Concentrate on how something needs to perform, when weighing up options and prices.

    3. Am I paying too much?

    Being new to the build process can mean people worry they are paying too much. Whatever your budget, you will want to feel that you spent your money wisely.

    While a huge budget may make some decisions easier, Will thinks you are better off being wise than being wealthy in terms of the build; of course money is critical, but getting the job done the way you want it is important too.

    A good way to better understand the process, without adding costs, is to network within the self-build and construction environment. Asking how people have used products and materials will help and you can even learn from other people’s mistakes.

    4. How can I find a reliable supplier?

    While big builders’ merchants might compete in terms of service and special deals, they tend to offer a similar selection of products driven by industry standards. Keeping things simple makes life easy for everybody concerned, but this means self-builders typically encounter problems when it comes to getting more in depth advice, especially on less common building techniques. Will explains, “What builders’ merchants are generally not keen to do is to invest an awful lot of knowledge at the counter front or in the branch, because they don’t see a return for it easily.”

    Will argues that there is a need to promote local builders’ merchants, who are more likely to support regional build systems or non-standard construction methodology.

    5. Who do I turn to for help and advice?

    A good starting place is looking at case studies and finding out what other self-builders are doing. For general help and advice, Will says it’s best to talk to someone who has done what you want to do.

    For technical or professional help, he suggests that a sympathetic architect who understands your ambitions can help find tradesmen with the right experience. However, Will also notes that when he has supplied some building companies with new materials, such as lime plaster for the first time, they realised it wasn’t too difficult and were happy to offer this new skill to customers.

    Other avenues of research include the Internet and roadshows. Will points out that this stage of the process doesn’t have to cost much, so it’s well worth testing the water before you spend a lot of money.

    Some of the relevant information might be too technical for the ‘average punter’ and this is where you might have to abdicate responsibility to the experts. For those wanting an eco-home, it can be hard to work out what that might even mean and the right questions to ask.

    Sustainability can mean different things to different people

    An eco-home could be summarised as: benign in construction, use and potentially in disposal. As Will says, “It benefits occupants’ health and wellbeing, it doesn’t pollute the environment and demands very low levels of energy.” He adds that most buildings built using eco principles feel like really nice houses!

    Some people worry that they aren’t creating the best possible eco-home, but self-builders need to set their own realistic goals. Will compares the desire for an eco-home to healthy eating. “Doing something is better than doing nothing. One salad a week is better than no salads a week. And we’re not expecting everybody to be vegan. There is a happy medium that is entirely personal to every single person.”

     

    Find out more

    Visit the website of Ecomerchant

    Follow Ecomerchant on Twitter

     

    Transcript

    Download a transcript of the interview with Will Kirkman
     

    The Future of Housing

    During our interview with Will he mentioned our documentary The Future of Housing.

    This explored the quality of housing in the UK and how we might improve the situation.

    There’s also a chance to see some exemplar projects.

     

    Please connect with me

  • HPH178 : Natural clay plaster wall finishes – with Clare Whitney from Clayworks

    HPH178 : Natural clay plaster wall finishes – with Clare Whitney from Clayworks

    Clare Whitney from Clayworks explains how clay plasters are made, their applications and why we might choose them over other wall finishes.

    Interview with Clare Whitney

    Clare Whitney has been working at Clayworks since 2009. The founders of Clayworks were specialists in cob building, even writing a book about it, and used clay onsite as a sustainable building product.

    Clayworks now manufactures natural clay plaster, having spent two years creating a consistent and tested product that can be ready mixed and made available to anyone in the world at any time.

    Clay is an ancient building material

    Clay is one of the most naturally abundant minerals. Clare says that clay blocks and clay building methods are being rediscovered all around the world as a sustainable material with relatively low carbon intake. Clayworks focus on the application of clay as a plaster.

    Clay plasters finish the interior walls of buildings

    Clay plasters are a mixture of clay subsoil, aggregates and some natural form of fibre, with clay acting as the binder. Clay absorbs moisture, so water intake is critical; too much or not enough affects the consistency. Clare explains that Clayworks comprehensively researched different clay minerals to get the mixture absolutely right, so that the clay will not crack or “dust”.

    Clay plaster differs from other wall finishes in several ways

    Clare says it’s hard to describe the aesthetic, as you really have to see and feel and sense them, adding, “It’s a completely different feeling to walk into a room with clay plasters.”

    Advantages of clay plaster include:

    A different aesthetic:• The patina is earthy and very soft
    • A slight texture gives depth
    • Clay doesn’t set, so you can create patterns and textures
    More sustainable than most other wall plasters:• Clay is a naturally abundant raw material
    • It doesn’t have to be quarried
    • The processing of clay plasters is minimal
    • Apart from transport, there’s relatively little embodied carbon
    Numerous health benefits:• Clay plaster helps regulate the moisture inside a building
    • Helps mitigate allergies and asthmas
    • Helps offset the effects of formaldehydes and indoor pollutants
    The robustness of the material:• The product is scientifically tested
    • Proven finish and durability
    • Transportable and widely available

    Clay plasters work with any type of construction

    Clay plasters are now used all over the world in cities and in steel and modern buildings. However they have typically been used a lot in straw bale constructions and buildings with a lot of timber, due to their moisture-absorbing properties, and also in Passivhaus and other buildings where sustainable building products are key.

    Furthermore, clay plaster helps to absorb odours and has very clear acoustic advantages, making it ideal for use in bathrooms and kitchens.

    Materials can be beautiful as well as functional

    Although their clay plasters were originally marketed on sustainability and health credentials, Clare says designers and architects have adopted them for their aesthetic qualities.

    Clayworks’ plasters are now being supplied to customers all over the world; Clare attributes this success to their ease of use and the fact they can be trusted to stay on the walls and hold patterns, sculptures and shapes. Commercially their clay plasters have been used to fit out of well-known chain restaurants and public buildings.

    You don’t need to paint clay plasters

    Clare makes the point that although their clay plasters are a little more expensive than other wall finishes (starting at around £20 per m2), the overall cost is probably similar because:

    • You never need to paint them
    • They are through-pigmented, so you won’t notice a discolouration if they become chipped
    • They’re easily repaired

    Part of Clayworks’ research included coming up with a very comprehensive range of colours using natural mineral pigments. Clare explains, “We make colours in a fairly infinite mix. We’re always making up colours to people’s specifications…we can do a lot of turquoises, blues, greens and we’ve even done pinks and purples over the years.”

    Different types of plaster have particular uses

    Clay plasters are ideal for internal walls and ceilings throughout a house. The only areas to avoid would be wet rooms and exteriors, where Clare would recommend lime plasters, as they are more water repellent.

    Clay plasters can also be used for feature walls and fronts of other surfaces such as kitchen interior bars and similar furniture-type applications.

    If you can plaster, you can use clay plaster

    Clare says you don’t need specialist skills as clay plasters are applied like any other plaster; it just takes a little longer because the clay is a slightly different consistency.

    There is a series of different layers and depending on the substrate, you would need different binders, which Clayworks supply. A base coat and topcoat then follow.

    Any good plasterer can use their clay plasters to achieve a plain finish, and artisan plasterers would be able to create specialist textured or sculptural finishes.

    Self-builders can learn how to use clay plaster

    There are lots of resources and support available:

    1. Call the Clayworks technical team who can talk you through every aspect of how to apply the clay; the services, substrates, primers and the entire plaster build-up.
    2. Visit Clayworks’ website for techniques and tips.
    3. Clayworks offer one-day training courses for professionals and novice plasterers.
    4. Self-help resources, such as Using Natural Finishes, can help you learn about the process of applying clay and lime.
    5. There’s a network of recommended professionals who have been trained by Clayworks.

     

    Find out more

    Visit the website of Clayworks

    Follow Clayworks on Twitter

    Transcript

    Download a transcript of the interview with Clare Whitney

    Please connect with me

  • HPH176 : A self build case study of ‘The Den’ Passivhaus – with Dennis and Nicola Merrigan

    HPH176 : A self build case study of ‘The Den’ Passivhaus – with Dennis and Nicola Merrigan

    Interview with Dennis and Nicola Merrigan

    Dennis and Nicola Merrigan talk about the highs and lows of their Passivhaus self-build project, sharing lessons learned.

     

     

    A ‘challenging’ plot at auction was affordable

    Dennis Merrigan had always wanted to build his own home and he loved the county of Dorset. He says they got lucky when their plot came up at auction, as they didn’t have to exceed their agreed budget. The neighbouring pub car park and pig farm may have put others off, but Dennis and Nicola are fond of the rare breed pigs and see the benefit of being close to the pub.

     

    The project inspired Nicola to become a Passivhaus advocate

    Nicola was initially overwhelmed by the build process and didn’t know what a Passivhaus was. The eco houses she had seen were on early episodes of Grand Designs, which normally showed “a sad looking woman putting sawdust down her composting toilet”! She was happy for Dennis to take the lead on the build but was adamant that she needed a flushing loo!

    As the build progressed she worked more closely with Dennis and fell in love with the story of Passivhaus. Becoming increasingly interested, she looked on Twitter for other self-builders. “Even though it’s something I’d never heard of before, I just thought it was really interesting and I wanted to learn more.”

    Planning permission informed the final design choices

    Dennis tweaked the existing planning consent to slightly increase the size of the house, but the planners turned down their initial red brick and stone design, saying they wanted something more modern.

    Dennis felt that “passive was the way to go” anyway, and had architect Paul Mallion of Conker Conservation in mind. Keeping Nicola in the loop, they tweaked the design as they went, deciding on timber frame for the construction. The second planning application imposed a height restriction but Dennis actually thinks the house looks better for it.

    Good neighbours can help to overcome challenges

    Dennis says they are lucky to get on very well with their neighbour. Together they solved some drainage problems for all concerned by using the neighbour’s suggestion of putting a sump on his land and building a drainage channel right through the Merrigan’s property.

    Manage the build with teamwork and communication

    During the build Nicola and Dennis were mostly away working, which Nicola wouldn’t recommend, saying that being near to the site is really important. However, with many phone calls to discuss details, client, builder and architect managed a lot of the project remotely. It was the builder’s first Passivhaus but being quite technical, he could understand the premise behind it. While Dennis’ architect only visited the site once during the build, he was very helpful on the phone.

    Dennis advises getting the building team onside for the air test. He says, “We played a little game on site that if they got it first time, there’d be a little bonus. And they did get it first time.” He adds that the air test is also a great way of testing that they’ve built it properly.

    Problems can become learning experiences

    The biggest challenge on the project came when the timber frame company went into liquidation. They had paid 50% upfront to have the timber frame made to their specifications.

    The contractor tried to minimise the damage by letting them take some of the materials and recommending another timber frame company. Good relations with the builder helped too, as he juggled his schedule.

    However, there was still a £20,000 deficit. Dennis’ tip to protect yourself against similar situations is to use a personal credit card for hefty deposits as that offers insurance.

    He remains philosophical, saying, “I think once you do get around things and overcome problems, then other problems that come up are very minor and you sort of get hardened to it.”

    Recycling can help solve budget issues

    They ended up with a lovely, finished house but no money left for a kitchen. However, Nicola says, “The gods of building take away and then give back.” Dennis works as an independent surveyor with loss adjusters on fire and flood claims. A very high-end kitchen shop had had a flood in the basement, but had a kitchen upstairs which had been written off. They were able to buy it at a manageable price and, though not the kitchen they would have designed, are really pleased with it.

    Nicola’s memories of the build process

    1. July 22nd 2012, first digger came to clear site

    2. Concrete was poured for foundations

    3. Timber frame went up – it looked like a house

    4. Siberian larch cladding went on – it looked even more like a house

    5. Fermacell boarding

    6. Kitchen went in – it was finally a home

    The little details make the difference

    Dennis says that finishing a property is all about detail. They have a good ventilation system but avoided ‘toys’, keeping things simple with timber floors upstairs and polished concrete floors downstairs. Details like aluminium guttering add refinement but nothing stands out on the roof. The solar PV panels are black and were built in. The solar thermal panels also ‘melt into the roof’, as they match the Fakro roof lights. (They also get the money back on the PV so they have a warm house and no bills.) Although told they wouldn’t need a log burner they put one in for looks. However, they are glad to have it to use occasionally when they haven’t been in the house for a while.

    The budget was difficult to manage

    Initial budgeting is hard and even Dennis’ builder wouldn’t work to a price having never done Passivhaus. Dennis agreed to pay the labour on a daily basis, so it was hard to stick to the budget. For example, the Fermacell is very heavy so took a lot longer and cost a lot more than plasterboard would have.

    Dennis admits that he made mistakes but they did have enough resources to finish the project. For example, they had to wait a little time but they did manage to get the kitchen.

    Nicola advises to not only budget for the house but also the surrounding area, something they didn’t do. Their neighbour came to their rescue again, doing the landscaping with his digger.

    5 tips for people wanting to build their own home

    Dennis and Nicola share some great advice for self-builders:

    • Be prepared: finding land is really hard
    • You need a good architect that you get on with
    • Get your finances in place – they used the Ecology Building Society and couldn’t fault them; furthermore, have a contingency; money can be a big worry, so don’t start without the project fully resourced.
    • Consider the form of contract; are you going to get somebody to do the whole thing or part-manage it yourself?
    • Especially with a Passivhaus, decide all the detail before you start because you can’t change things easily; even moving the structure inside is very hard because of the ventilation system.

    Dennis notes everybody will have different challenges with the build itself. However, once you’re in the house and benefitting from it, you forget all the problems. He concludes, “It’s worth doing. I’d recommend it, but you need to know what you’re taking on.”

     

    Find out more

    Conker Conservation

    Follow Nicola on Twitter

    Transcript

    Download a transcript of the interview with Dennis and Nicola Merrigan

    Please connect with me