Tag: low energy

  • HPH138 : Why an integrated design approach works well for self build – with Charles Grylls and Nick Grant

    HPH138 : Why an integrated design approach works well for self build – with Charles Grylls and Nick Grant

    Charles Grylls and Nick Grant explain what is meant by integrated design and how it can benefit a self build project.

    Charles Grylls
    Charles Grylls – Dempsey Decourcy Architects
    Nick Grant - Elemental Solutions
    Nick Grant – Elemental Solutions

     

    Interview with Charles Grylls and Nick Grant

    For the last 5 years, architect Charles Grylls has been working with a design team on Passivhaus projects in Herefordshire. The team includes Nick Grant (Passivhaus Consultant), Alan Clarke (Services Engineer), Allan Pearce (Structural Engineer), and Mike Whitfield (Contractor). Although they are independently employed they collaborate together on projects, which benefits the client but also develops their expertise and aids their understanding for the future.

    Their first project working together was a Passivhaus in Garway, which has led on to subsequent builds.

    Garway
    Garway – Photo by George Mikurcik

    As Nick explains, traditionally it tends to be that the architect draws something, the engineer has to try and make it work, and the builder has to try and build it. A collaborative approach from the outset enables non-hierarchical input and advice, working together, to make the project a success.

     

    Working relationships and connections were already in place

    Charles knew Nick and Mike from working with them when he was an employed by Architype. Mike and Allan Pearce had both been involved when Nick had built his house, so there had already been working relationships in place for 15 years or so.

    Nick said: “We’re a bunch of friends. I know it’s often not the best thing to work with your friends, it can be a recipe for disaster, but we get on well and we respect each other.”

    It did take a few weeks of working together as an integrated team to understand what each members’ role would be and what each would be bringing to the design team.

    Nick stresses that although it’s an informal arrangement they have, it is based on trust and responsibility. The contractor particularly is seeing problems on site through the eyes of the rest of the team and has a responsibility to notify the others if they think something needs doing.

    Charles Grylls and Mike Whitfield
    Charles Grylls and Mike Whitfield

     

    There can be less risk using a negotiated tender process

    In a traditional contract a client would work with an architect from concept through to a detailed design, which would then go to planning. Once planning has been achieved it might go out to tender, so already you’re a long way through the process before even speaking to a contractor or consultant about how to build it or how to solve energy problems.

    Charles sees there being risks in terms of cost and quality control using builders through this process who don’t have Passivhaus experience. His experience of competitive tendering for a Passivhaus project is that they will either come in with a low price because they don’t understand what they’re going to have to build, or price it for risk and so overprice it. Using a negotiated tender process, which is still a traditional route to go down, can be less risky.

     

     

    It’s about quality and people who care!

    Nick says that you don’t necessarily need to find a builder or team members who have had Passivhaus experience, but they just need to care about what they’re doing. Often smaller builders will be at a disadvantage when it comes to tendering because they don’t have a department specifically geared to do that, but Nick says they’ll happily turn up, do the job and work for a fair price. By finding a small builder and speaking to previous clients, you could end up with a cheaper and better job.

     

     

    Good, but not superfluous, communication is required

    The team collaborate using shared folders online for consultants’ information so that everyone can cross-check, evaluate and provide an immediate response to information that goes out. The client can also be included in this way. They also make sure that people are only involved when they need to be, so their time is not being wasted.

    Being a group of friends, some of the team’s communication takes place down the pub, chewing over challenges and working out solutions and better ways of doing things in the future!

    Charles stresses that as a client, starting off with a good brief, keeping on-site changes to a minimum, and ensuring that communication lines are kept open throughout are some of the most helpful things you can do. He suggests a flow diagram can be useful in showing members’ roles and responsibilities if it gets complex. Within this team it tends to work slightly differently from a traditional procurement where the architect is project manager and administers the contract, because Mike (the contractor) forms a contract direct with the client. Charles explains that this keeps things simple because everything has been worked out between the team beforehand so there are not usually too many changes.

     

    Establish and be honest about your budget from the outset

    Nick explains that sometimes when projects are drawn up and put out to tender, they come in way over budget and so then go through a “value engineering” process to strip out all the good bits to make it affordable. Far better is to establish a budget and be honest about what that is. There’s no point in being coy and saying your budget is lower than it is because the danger is the design may not then include the features that you might have desired but, according to your stated budget, couldn’t afford.

    Having the builder involved early on is an advantage because they can give input from experience on how much things are likely to cost, so things are not added to the design that may later need to be removed because of budget constraints.

     

    Reviewing the finished project benefits the team as well as the client

    Going back and seeing how the building is performing can help the occupants establish whether it’s being used to its full potential and whether any adjustments can be made to increase comfort, etc.

    As Nick says, the team are only likely to be offering this if they’re fairly confident there won’t be too many problems! If there are problems they want to know about them and learn from them, to avoid them from happening again.

     

    Transcript

    Download a transcript of the interview with Charles Grylls and Nick Grant

     

    Find out more

    Visit the website of Dempsey Decourcy Architects

    Visit the website of Elemental Solutions

    Follow Charles Grylls on Twitter

    Follow Nick Grant on Twitter

     

    The Hub update

    We are currently looking for our next self build project to follow in The Hub. Ideally it would be a Passivhaus that is different from our first case study Long Barrow (e.g. not built with insulated concrete formwork) and again we would focus on the decision-making process from the design stage right through to construction.

    If you think you have a project that may be suitable, then please do get in touch and tell us about it.

     

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  • HPH135 : Tips for buying land at auction – with Tom Gresford from Gresford Architects

    HPH135 : Tips for buying land at auction – with Tom Gresford from Gresford Architects

    Architect Tom Gresford shares his experience of buying land at auction.

     

    Interview with Tom Gresford

    Tom Gresford of Gresford Architects qualified as an architect in 2002, set up his own practice in 2006 and for the last 5 or 6 years has been increasingly focusing on low energy and sustainable design.

    Tom finds auctions an interesting way of purchasing unusual properties and quirky development sites that perhaps aren’t found on sites like Rightmove, and he has bought 3 or 4 using this method himself.

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    Do your research and employ a planning consultant

    Buying at auction is much the same as buying any plot, in that you should do your research first, even though there’s no guarantee of being the successful bidder. Tom recommends hiring a planning consultant to do 5 or 6 hours of work on the site and local appropriate policies, probably costing around £500 or £600, to advise on the likelihood of gaining planning consent.

     

    Look for potential where others may not see it

    Tom explains that because the market is quite overcrowded, he tends to steer away from anything straight forward. Instead he looks for quirky or unusual things that other people might not think they can do anything with. His Chieveley Passivhaus was an old water tower which was one of 6 assets being sold by Thames Water at a Savills auction. He did a planning study for each of the 6 and identified this as being the one most appropriate for development.

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    However, there are never any guarantees in development! Tom gives an example of a site he purchased in Staines. Because it was on a flood plain they fought to try and get planning permission for 2 years and went to appeal, before deciding to sell the plot on. Tom thinks there will also be people willing to pick up these pieces of land, as they may have different intentions for its use.

     

    You should always go into an auction with a limit!

    Tom says that you should always decide in advance what the maximum you are prepared to pay will be. Without that you may end up paying considerably more than the land is worth. You should go in having an idea of the land’s value, so if you had to exit the deal you would know how much you could expect to get back on it.

    Deciding what price you’re prepared to pay may also be dependent on your motives for buying. If you’re buying it to build your own home then you may be willing to pay more than if you’re buying it as a development opportunity. Tom does say that the majority of people at these auctions are professional investors, but that you can always spot who are the self builders!

    “There’s no rule of thumb and you never know who you’re going to come up against, how deep their pockets are and what they might be thinking on the day.”

     

    Buying at auction is an incredible adrenaline rush

    Tom has lost out on far more bids than he has actually won, but says there can be an incredible adrenaline rush, particularly if there are quite a few people bidding. He tends to wait for a while before starting to bid, and is always clear with himself what level he is prepared to go to. He says if for example you get to that limit and there are still 3 other people in the bidding for it then you know you’re not going to win and just have to walk away.

     

    Try to remain aloof and detached

    While it can be a thrilling experience, Tom advises caution in getting carried away because it can be a real emotional rollercoaster. That is particularly likely to be the case if you’re buying the site to build your own house.

    “You wouldn’t choose to buy somewhere if you didn’t want to live there, but then the very fact you want to live there will mean you’ll get emotionally attached to the idea.”

    Trying to remain aloof and detached is a good way of helping you to bid in a sensible manner, and also help you deal with the emotions of potentially not having the winning bid, which statistically you are unlikely to have.

     

    The brief for Chieveley Passivhaus was based on an imaginary family

    Because there was no client for this build, Tom had to imagine a scenario around which to design. They worked on knowing what tends to be popular, which is a 4 bedroom house, the master bedroom having an en-suite, a family bathroom and then a downstairs toilet. Their imaginary family were interested in modern design and were concerned about the environment and low energy living.

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    When the house was put up for sale they received 3 sealed bids from 3 sets of people with very differing profiles. None of them previously had an interest in Passivhaus but saw it as a massive advantage.

    “We were showing that you could build beautiful modern houses in the Passivhaus way.”

    They went down a construction management route of procurement so Tom believes that despite it being a Passivhaus it probably cost the same as most people would build a standard house. If you used the same procurement method but not built to Passivhaus then it would have been cheaper because there are elements such as the blinds, triple glazed windows, MVHR etc that totalled around £15,000, that you don’t have on standard buildings.

    With the house being west facing to take advantage of the views, they have used manual blinds to take advantage of winter solar gain without having the problems of overheating in the summer.

    IMG_1125

    “It’s just a really good house. A really good, well designed, beautiful, comfortable to live in house…It demonstrates that you can live a really comfortable life with having absolutely minimal impact on the environment and the dwindling resources that we have to face up to.”

     

    Transcript

    Download a transcript of the interview with Tom Gresford

     

    Find out more

    Visit the website of Gresford Architects

    Follow Tom on Twitter

     

     

    The Hub update

    The Hub draws on our experience of video and audio production to bring you more in depth information to help with self build projects.

    Our current video case study is following Alex Baines’ Long Barrow Passivhaus project, which is an insulated concrete formwork, semi earth sheltered construction. We’ve worked our way up from the basement to the first floor ICF walls and soon we’ll be going into the roof.

    We also have our private Facebook networking group and we’re coming up to the first of we what we hope will be quarterly progress calls, where we can get together and discuss how our projects are going, trying to help with any problems, and we might even bring in a guest or two from time to time to help with any queries.

    If you want any more information then check out our video which will give you an overview of what you can find in The Hub.

     

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  • HPH014 : Low Energy Barn Conversions – with Bill Butcher from Green Building Store

    HPH014 : Low Energy Barn Conversions – with Bill Butcher from Green Building Store

    Bill Butcher from Green Building Store shares his approach to creating a low energy barn conversion by building a box within a box. Stirley Community Farm will meet the EnerPHit standard.

    Bill-Butcher

     

    Interview with Bill Butcher

    Bill started out, aged 16, at the tech college in Exeter doing an HNC in building. From there he pursued the quantity surveying route, before becoming a builder. He has always had an interest in the environment and founded Green Building Store with two other colleagues in 1995. Green Building Store focusses on supplying the components and services around low energy and sustainable construction.

     

    In 2007 They Realised The Potential of Passivhaus

    Bill tells the story of how his business partner, Chris Herring, had been over to Bregenz for the Passivhaus International Conference and had come back convinced that their business should go down this route.

     

    An Opportunity Presented Itself in Denby Dale

    When Geoff and Kate Tunstall approached the Green Building Store about constructing a ‘green house’, which in their eyes was going to be a dormer bungalow with a low of renewables, it presented the perfect opportunity to construct their new home to Passivhaus standard. In 2009, they started building. You can read a comprehensive blog on the whole project.

    Denby-Dale-night

     

    To Keep The Price Reasonable, Builders Will Stay Within Their Comfort Zones

    As Green Building Store had built with masonry and cavity wall in the past, this was the approach taken at Denby Dale. This meant that all the materials were available locally in Huddersfield, with the exception of triple-glazed windows with insulated frames, mechanical ventilation heat recovery (MVHR), and various tapes and membranes (all of which are now handily stocked by the Green Building Store!).

     

    Passivhaus is Not Restricted to a Single Construction Methodology

    Bill talks about other examples including John Williamson from JPW Construction building with timber frame and Bere Architects using a kit home imported from Austria for the Camden House.

    Denby-Dale-kitchen

     

    Passivhaus is as Much About Comfort as Anything

    Benefits of a fabric first approach not only include the performance of the building, but you also create an environment that is tranquil and comfortable. Even when it is -10°C outside there’ll be no internal surfaces less than 17°C. This drastically reduces convection. Bill explains with an analogy of standing in front of a fire on Bonfire Night, where you’re burning on the front side but freezing on your back! In a Passivhaus where you don’t have that convection of cold air falling you can keep the thermostat down to 18°C, whereas in a conventional build you might have to adjust the thermostat to 23°C to counteract that feeling.

    Denby-Dale-window

     

    Stirley Community Farm

    These were three bankrupt dairy farms on the outskirts of Huddersfield (in quite an exposed location) that were owned by Kirklees Council. Yorkshire Wildlife Trust took them over, and recognising that wildlife and farming are intertwined, they are now running the farms quite traditionally with minimal fertilisers. In addition to rearing a herd of beef cattle, they are growing food, and also showing how this can then be prepared and cooked inside the new education centre.

    Stirley-Community-Farm-barn-before-EnerPHit

     

    The Building Was Structurally Unsound

    After getting in the structural engineers, the existing buildings were found to be unstable. Therefore a lot of work had to be carried out on making the building stand up by underpinning the foundations. The foundations themselves were very minimal.

    Stirley-Farm-Artist-impressionAn artist’s impression of the new Stirley Community Farm, courtesy of Eco Arc

     

    Insulation is Put Under The Floor

    Bill explains the process of excavating down in order to insulate underneath the floor (200mm of polyurethane underneath a 6-inch concrete slab with the hard core). Alternate 1m by 1m concrete pads are also placed under the existing wall to stabilise it.

     

    Creating a Box Within a Box

    As a barn is just an open space, the pioneering approach on which they settled was to construct a timber frame building within the existing masonry. At the same time the existing masonry would be stabilised with the timber frame, and the envelope would be insulated and made airtight. The two structures will then be separated by a nominal cavity. Bill goes into more detail.

    Stirley-Community-Farm-Ground-Floor-Proposed-plan-High-Res

     

    A Building With No Windows or Doors Would Be More Energy Efficient!

    Bill explains to Ben that you can build a wall to a U value of 0.1 quite easily (which is currently 3 times better than building regulations in the UK). However when it comes to the windows and doors, even using the best components, you might get to a U value of 0.8. That’s 8 times worse than the wall next to it. Therefore how that’s installed in the wall is crucial. The frame must be wrapped with insulation from the walls or so that it’s continuing the insulation around the frames. They are a thermal bridge in their own right.

     

    Thermal Performance as Important as Keeping The Rain Out

    Bill believes we have to look at the concept right from the beginning in a different manner where thermal performance is as important as keeping the rain out. He stresses that you wouldn’t want steel balconies cantilevering out of your buildings because steel is one of the worst conductors of heat.

     

    Construction Industry Has an Opportunity to Raise its Game

    Buildings of this quality demand attention to detail, and skill and teamwork are more important than ever. This is not the last bastion of a school leaver. It is also an opportunity for the whole team, including the client, to gain a better understanding of what the project is about.

     

    Putting Tenders Out to 10 Builders Will Never Lead to High Performance

    Bill suggests a procurement method in which we put out tenders to 5 or 10 builders will never lead to high performance, because the builder hasn’t any ownership over the project. It’s far better to get a builder in partnership during the design stages so they can have their input into the design.

     

    Sources of Moisture

    The problem with moisture in buildings can come from several different angles. One is groundwater, which is why people use damp proof courses and so on, and tanking when below ground. There’s also moisture from wind-driven rain through a wall, through masonry because stone brick is porous and it has to be dealt with in one way or another.

     

    A Well-Ventilated Cavity Will Avoid Solar Driven Moisture

    Solar driven moisture is less well known. It can happen in the summertime and is a danger where you’ve got a radical construction. Once you’ve extremely well insulated internally, the external masonry wall will be colder and it becomes more like a garden wall (lime based mortars breathe, allowing moisture both in and out of the wall).

    When you’ve put internal insulation in with a complete air tightness layer, what can happen in the summer when you have a heavy rainstorm is that the wall gets very wet. After that the sun comes out and the heat from the sun drives the moisture inwards. If you haven’t got a well ventilated cavity, that moisture could potentially soak the timber frame inside. There was an example in Belgium where this damage occurred because there was not enough attention to detail during the planning stages.

     

    WUFI

    A software program called WUFI allows you work out the minimum air change rate that should be acceptable (in the cavity in this case) in order for moisture to be taken away as vapour. The calculation for this project shows that it is only if the cavity goes below 8 air changes per hour that there is a danger that moisture could start building up in timber frame. In other words, it can be designed out.

    StirleyCommunityFarm-positioning-concrete-wall-connectors

     

    Not Practical to Have Every Building With Moisture Sensors

    Stirley Farm will have moisture sensors but Bill suggests that it would be impractical to do it on every new building.

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    Green Building Store’s Free Resources

     

    Transcript

    Download a transcript of the interview with Bill Butcher.

     

    Ask Your Questions or Share Your Feedback

     

    3 Videos on Energy-Efficient Homes

    Ben has been filming with former podcast guest Martin Evans from the Malthouse Consultancy. There’ll be 3 informative videos coming soon.

     

    Google+ Communities

    If you’re reluctant to take on more social media, find out why Google+ is important. We have set up 3 communities – Eco Homes, Energy-Efficient Homes and Passivhaus – which we’d love you to join.

     

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