Tag: new build

HPH329 : What does a structural engineer do? – with Beth Williams
Beth Williams from Build Collective outlines the role of a structural engineer and explains what tasks might be undertaken on a house build.

Interview with Beth Williams

Beth had wanted to be an architect since she was a teenager, and graduated from university with a degree in architecture and structural engineering. However, at the time she graduated, the UK was in the grip of a recession and the only job opportunities she found were in structural engineering. Part of the reason she has since gone on to work in the low-energy space, is that she enjoys the close working relationship with the design team.

Beth is a Chartered Civil Engineer and Certified Passivhaus Designer. She is an associate at Build Collective; a bespoke engineering consultancy in Bristol.

Structural engineering is a sub-discipline of civil engineering

Civil engineering sits at the top of the hierarchy. It covers things like highways and drainage.

Structural engineering is a specialism within that, but can still be quite broad. Structures can mean a focus on things like bridges and masts, or it can be for buildings.

So if you’re looking for a structural engineer for your project, you can either opt for a chartered civil engineer (with a specialism in structures), or a chartered structural engineer. Beth explains that there isn’t really any difference in terms of insurances and liabilities. The qualifications to look for are: the MICE (Chartered Member of the Institute of Civil Engineers), and the MIStructE (Chartered Member of the Institute of Structural Engineers).

They work as designers, under the principal designer

If there is no architect on the project, such as for a small domestic knock-through, then the structural engineer may take on the required role of principal designer looking after health and safety.

For most other projects though, the architect is the principal designer. They coordinate the flows of information between the design team members, and produce a pre-construction pack. That is all of the information from all of the designers, and all the health and safety risks. This is then passed on to the principal contractor to take as their responsibility once the construction phase gets underway.

Small projects might not need a structural engineer

If you are redecorating or moving an internal wall that isn’t structural then you probably don’t need a structural engineer.

Part A of the Building Regulations gives a generic outline of the structural principles, which could be used by an architect to design a very limited building such as a garage or an extremely basic house.

It used to be the case that people doing architectural work would have cover in their professional indemnity insurance for designing small structures. However, since Grenfell and a number of basement collapses in London, a lot of them have lost those insurances so the work has come back to the structural engineers.

Domestic clients will usually pay a fixed fee

Larger projects tend to be costed up on a percentage basis, whereas domestic clients are likely to pay a fixed fee for the defined scope of works. Beth’s advice is to always check what is on the scope of works, and the number of passes included.

A lot of engineers base their fee on responding to a set of drawings once. Build Collective however, do a two-stage pass. This involves some rough sizing and layouts as a preliminary design. The architect uses that to develop their details before returning to the structural engineer for their detailed design. Having that extra pass allows for tweaks to be made based on new knowledge that might be acquired during the process, such as ground conditions for foundations.

Many factors impact on the structural system

Corner windows, fancy overhanging roofs, and flat roofs are just a few elements that will impact the structural system. This all feeds into the “Have I got enough wall?” question, which is for the structural engineer to answer. Things like large glazing and an open plan design will all obviously limit the amount of wall that they have. So it’s about how much wall there is to make the structure stand up, and evenly distributing it throughout the building. Large stair openings and double-height voids mean there is less floor area to be able to distribute the loads.

Where there aren’t walls, it might mean putting in portal frames or goalpost frames to give stability.

It’s not just the vertical loads that need to be considered either. They also need to factor in whether the walls can withstand the horizontal load when wind is blowing on them.

Local structural engineers may have better knowledge of ground conditions

One advantage of hiring a local structural engineer is that they will be familiar with the area and its challenges.

For example Beth says that there are many cheap building plots in Bath because the ground conditions are often horrendous. It has a lot of historic landslip material that is volatile to work on. And Bristol has lots of coal mining areas and slope stability issues that will prove challenging.

Beth suggests a good use of money would be to pay a structural engineer for a few hours to look at geographical maps for your site and provide advice.

She would also recommend having a proper geotechnical survey for a new build, which costs around £3,500-£5,000. This involves a specialist geotechnical engineer doing bore holes or trial pits. They will log the findings and send samples away for lab testing, and report on the different structural and chemical properties of the ground.

If you can get a good ground investigation early on, you mitigate a lot of potential risks that could occur later on.

Your foundations will depend on your ground conditions

There is a range of sizes of ground particles, from large rocks down to gravels, sands, and clays.
- Rock – For rock at depth, you might be able to pile down onto it, and lock onto the top surfaces
- Gravel – Can be very flexible and have good bearing capacity
- Sand – These can be good because they don’t have the same volume change potential you get in clays
- Clay – Clay heave can be an issue. The clay will swell and shrink over the seasons as it takes on more or less water. To get around that, you dig deeper to where the clay isn’t affected by the heave. That may then be too deep to dig safely, so would need piling
Concrete may be something that you’re keen to avoid but it does have its place.

Beth uses a lot of insulated raft slabs on low energy projects. It’s a good solution for timber frame projects because you need some weight in the building to hold it down. If you are going to use concrete the important thing is to use it efficiently.

Another foundation option could be screw piles. They have some tension capacity in order to do the uplift for a timber frame. However, they’re not going to be possible in every scenario, and Beth warns against clients fixating on them before knowing whether their ground conditions will be suitable.

(AECB members can access a webinar recording of Beth discussing alternatives to concrete foundations.)

The design starts with the roof

Beth uses a top-down approach, starting with the roof design. This is followed by any suspended floors, then the walls and lintels in the walls.

Even before she does these vertical load takedowns, she will look at overall stability. This incorporates the wind and snow loads.

A surprising level of information is needed to do the structural design

There are lots of things that feed into the structural design that may not be immediately obvious.

Staircases are a good example. Where there’s a stair opening going up through the floors there needs to be a stair trimmer. There may also be a balustrade to prevent falls. What that balustrade is made out of will impact the structure. Glass obviously has more significant limitations on the deflection it can take before it cracks, than a lot of other materials. It has different fixing requirements too. Another consideration is how the balustrades for the stair itself join onto the rest of the balustrade.

When clients arrive with a specific product that they want to use, Beth sources all the data from the supplier in order to do the design. She has developed her foreign language skills because often the technical information isn’t supplied in English!

Don’t be afraid to involve an engineer early on!

This is especially the case if there is a specific product or system that you want to use. Get advice early to see how that might impact what the structure looks like, where the windows might go, and how many walls you might need inside. Beth would then do preliminary rough structural layout markups, ahead of planning, to show where the beams and frames could go. The architect can feed this back into their designs.

Find out more

Visit the website of Build Collective

Follow Beth Williams on Twitter

Transcript

Download a transcript of the interview with Beth Williams

Calling future engineers

Water expert Cath Hassell has featured on the podcast several times before (discussing topics such as saving water, rainwater harvesting and dealing with sewage). However she is also the creator of the Frankie the Flamingo series of books for children. So if you have a budding engineer on your hands perhaps The Mysterious Case of the Elephant that Forgot is a good place to start.

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March 15, 2023
HPH295 : How to connect a new electricity supply to your home – with Neil Clarke from UK Power Networks

Neil Clarke from UK Power Networks explains how to get mains electricity to a new build home.

Interview with Neil Clarke

Neil has been working for UK Power Networks for over 32 years, and currently heads up their connections services division. This covers new builds of up to four plots, highway services (bus shelters, speed cameras, streetlights), as well as the disconnection side when buildings are being demolished.

The main electricity network is broken into 12 separate regions, which are owned by six different companies. UK Power Networks cover the Eastern, South Eastern and London regions. Their role isn’t to generate electricity, but to enable its distribution, through maintenance of the wires and sub-stations in the network.

If you’re not sure who your distribution network operator is there’s a useful search tool on the Energy Networks Association website.

New builds account for 40% of their connections

UK Power Networks receive around 60,000 inquiries a year for small, domestic connections services. This generates around 24,000 quotes, with approximately 60% take-up.

Applications can be done online

There are two approaches that customers can take to get the connection process started. The first is to complete an online application form, which is something that regular customers would be most likely to do.

For anyone that needs a bit more help, the second approach is where the customer can request a site visit. A representative will arrange to meet the customer at the site, talk them through the process, and assist with filling in the application form and processing it through the system.

They provide online videos and tutorials to assist with the application, whether it be for a new service, an alteration, connection on the highway, an electric vehicle charger, etc.

They will work with the homeowner or their electrician

Neil says that if someone is making an application then they usually know roughly what it is that they need. Sometimes this will be because the homeowner will have an electrician applying on their behalf.

If that’s not the case then Neil’s department will work with the homeowner to explain what kind of supply they would need. Most houses would be a single phase, one-hundred amps. But if they have larger pumps and machinery then a three phase might be needed to even out the voltage across each phase.

Their behind the scenes technical checks will be included in the price and will look at volt drop, the size of the substation, any differences for being in a rural area where there’s no electricity, etc.

Larger developments of four units and above will be handled by a different department, as they may need to have network reinforcements.

“All we’re trying to do is support the integrity of the network, to make sure that whatever we supply is sufficient for the homeowner but also fits in with the network.”

Anything is possible, but there will be costs attached

Neil says that even in rural areas anything is possible. But it’s worth considering if you’re having problems with getting an electricity connection, then you’re likely to also have issues with getting water and gas to the site too, and at this point the decision might be that a self build isn’t going to be viable.

The most efficient and cost effective way of going about it is to tie-in with the other utilities, rather than trenches needing to be dug each time. When permits are requested from the local authority they can say whether gas and water are going in, and there can be a collaborative working between them to reduce costs and disruption, and get the work done more quickly.

Their responsibility isn’t as a supplier or meter operator

UK Power Network’s responsibility is up to the termination, from the house outwards. This termination will be 100 amps. From there, a single or a three-phase cable will come out of the property, into a ducting which is usually on their property and runs to their boundary line. At that point it goes to the public footway, or possibly across the road, depending on where the mains cable is.

Plans of where the cables are, are available from their plans provision team, but in the case of a new connection, a surveyor would be sent to map out all of the cables and plot them on the drawings. These are cross-checked with their logged records to make sure they match up correctly.

Staff receive continous training

How many UK Power Networks staff you have attend will depend on the site specifics. Generally, in addition to having a surveyor visit, the field staff will usually come in teams of two. This could include a civils gang, a jointing gang, and a reinstating team.

All staff are fully trained and have refresher sessions every six months to keep their competency up. At six month intervals they are also monitored and tested on site, and have regular safety briefings.

Costs are dependent on a number of factors

Every job will be site specific, but there is a basic cost for a new supply into a house. This would be sufficient for most houses, whether detached or otherwise, and covers up to 40m. Anything greater than 40m and they might need to lay a three-phase cable to stop volt drop, which would start to put the price up.

Other things that may prolong the process and add to the costs, can include having to cross a high-pressure gas main, which would need a specialist on-site for safety reasons, or needing to apply and give notice for a road closure. Other road conditions that could impact the cost, might be if specialist traffic management is needed, parking bay suspensions are required, or if it is crossing red routes.

Underground supplies are preferred

If the property is in a rural area and the only supply is overhead, then they would supply that property overhead, but generally they try to avoid working at height and run it underground into the property if possible.

Cables that are laid in the road are between 600mm and one metre below the ground. In the footway they is usually a minimum of 450mm deep.

The cables are plastic coated with an aluminium core and a copper neutral.

Programme timings can be driven by the customer

At an initial site visit, you might be advised to install a temporary builder’s supply (TBS) for use while the building work is being carried out. This would need to be in a lockable, waterproof housing and could be changed to a permanent supply if required later.

UK Power Networks will provide a quote within 5 days of the application being submitted.

Once the customer has paid they aim to provide the supply within 25 days, on a date of the customer’s choosing. Five days before the date of supply they will call the customer to check everything is on schedule, and a couple of days before they will pop by to check everything is ready.

Contact them as early as possible

Neil’s advice is to communicate with them as early as possible, even if it’s just to understand a process or how much it’s going to cost. He uses disconnections as an example, where a site has been demolished but their termination has been left standing, potentially being a danger to the customer or their staff.

Other parties involved could include electricians and a meter operator, so it is important that early communication involves those parties to ensure everyone is collaborating effectively.

Find out more

Visit the website of UK Power Networks

Follow UK Power Networks on Twitter

Transcript

Download a transcript of the interview with Neil Clarke.

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December 16, 2020
HPH266 : How to invest sweat equity into a project while maintaining quality – with Ajay Boardman and Nigel Bowley

Client Ajay Boardman and her builder/carpenter Nigel Bowley share their experience of working together on her self build project. In addition to project managing Ajay is labouring for Nigel. We look at why this relationship has worked well and consider how much money she is saving.

Interview with Ajay Boardman and Nigel Bowley

Ajay is building a 260m² Passivhaus in the South Downs National Park, using the PH15 build system. Having found Nigel Bowley to build the timber frame, it seemed natural that, being a practical person who didn’t have a job at the time, Ajay herself would take on the role of project manager and labourer.

Parental support has been invaluable

A big factor in Ajay being able to take on the project has been the support of her parents who live on a farm next to her and the site. Having plenty of experience helping her dad out with manual work on the farm has stood her in good stead for transferring her skills to the building project.

Not only has her dad helped out with the labouring when she has needed a break or to concentrate on the project management side, but he also always has the right tools for the job. In addition, Ajay’s mum helping out with childcare has meant that Ajay has been able to put in the extra hours while still having the children close by.

Nigel and Ajay quickly realised they would have a good working relationship

A carpenter by trade since joining a YTS scheme in 1986, Nigel has had a varied career working on projects such as house building, extensions, internal renovations, roofing and some commercial work. He is equally used to working on his own or having a small number of sub-contractors and labourers alongside.

From previous experience of working with labourers, Nigel had his doubts about how successful having Ajay and her dad work with him would be. However, Ajay soon demonstrated that she had a great interest in the building, listened, followed instructions and had good manual coordination and skills.

Working on a weekly payment basis rather than a contract, Nigel had the ability to walk away if he needed to, but after a successful first week levelling the site they both realised they would be able to work together well.

They also found that their different skills complemented each other well. Where Ajay’s knowledge of the parts and the process was lacking, her admin and communication skills helped take what was in Nigel’s head and translate it into something that she could work from.

Breaking the jobs down makes the whole process less overwhelming

Nigel explains that looking at the entire job and thinking about what needs doing can actually be pretty overwhelming. He tries to keep things more simple by breaking each job down into smaller parts. That way the focus only ever has to be on those few things that are needed over a short time span.

Doing it yourself gives you control over the quality

Having been to see a different PH15 house, Nigel was confident about the timber frame aspect and getting it level on the slab. Moving forward they may get an electrician and possibly a decorator in, but the rest of the work they are keen to do themselves. This includes the MVHR and all the taping and joining because they are so aware of the importance of getting it right for the airtightness.

Ajay and Nigel have found a happy balance in what they each need to control based on their individual skills, without controlling each other. While Nigel is in control of the job, he’s also answerable to Ajay’s quality control. This method has worked for them and hasn’t caused any conflict.

Nigel’s tips for anyone else in a similar situation would be around communication: listening to each other and knowing your boundaries on what to say and when.

Quality hasn’t been compromised by the cost savings

Taking on the role of labourer and project manager has obviously been a cost saving for Ajay, and by taking jobs like sweeping up and placing orders away from Nigel, it means his time can be spent more productively.

Having a relative novice alongside and working out things like the airtightness has meant that the speed of work has sometimes been slower than on his other jobs. However the quality hasn’t been compromised, with architect and co-creator of the PH15 system, Jae Cotterell, crediting the workmanship being of very high quality and better than a lot of professionals.

It’s physically very demanding

Nigel believes that sweat equity can work whether it is a PH15, masonry or other build system.

“I don’t think it matters on the style or the type of building. It’s just really if you’re prepared to work, properly work. Because I don’t think a lot of people really work that hard when it comes to physical.”

But doing it themselves has allowed an element of flexibility when it comes to working hours and fitting in around school runs and other responsibilities.

They are not working to a programme

Nigel is used to working to a programme, so not having one on this project has been one of the hardest things for him to adjust to. He is used to setting an ambitious timeline in order to keep the labourers motivated.

“On previous jobs, you can burn your labourers up quite quickly and they become unmotivated and they leave pretty quick. So, you’ve got to really manage their physical abilities, your own physical abilities, and so you kind of have to let the job lead you in that way really. And knowing when that is going to be a physical effort, a mental effort, a slow part of the job.”

It’s more about the process than the end result

With a few months left on the project, Ajay is relaxed about how the house will turn out. For her, the greatest satisfaction is the process of making it, though the air quality and comfort that comes with it being a Passivhaus is something she is particularly looking forward to.

Passivhaus Workshop

If you’re new to Passivhaus and want to find out more about it, then check out the National Self Build and Renovation Centre in Swindon which is running regular workshops. There will be explanations of the key principles along with case studies and demonstrations.

Find out more

Visit the website of Nigel’s South Downs Eco Homes

Find Nigel on Facebook

Read more about the PH15 build system

Transcript

Download a transcript of the interview with Ajay Boardman and Nigel Bowley

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October 9, 2019
HPH231 : How to design an interior for a modern home – with Gabrielle Blackman
Interior Designer Gabrielle Blackman explains how, when planned properly, good interior design should take the owner’s personality and stamp it on the house.

Interview with Gabrielle Blackman

Gabrielle Blackman trained as an artist and found that with interior design she was able to combine that with her passion for being hands-on, busy and working with people. Her career has seen her work in interior yacht design as well as with some of the leading designers around, before taking the step of starting her own company.

The line between interior design and architecture can cause on-site conflict

The use and practicality of the house can sometimes come into conflict with the architecture.

“So, an architect might want a floor-to-ceiling piece of beautiful glass, so you’re celebrating the space of the room and all of this wonderful natural light, and then I come in and say, ‘where are we going to put the furniture? How are we going to store stuff?’”

Gabrielle explains that there is always a bit of give and take involved and often some heated discussions, but it’s a healthy and robust relationship which as a result produces the right house for the client.

“But we get something amazing at the end of the day because it’s two skills that slightly butt heads, but you create something beautiful.”

It should feel full of personality, be incredibly practical and look amazing

Gabrielle believes that a good interior designer should be able to interpret their clients’ personality and stamp it on a building. What is also important is that the client feels immediately natural and comfortable within it, and not as though they are in a show home. That is something that comes about through the collaboration process.

“All the details that might be overlooked by exhausted clients who are under a barrage of decision making every day and having to deal with contractors, an interior designer should be able to come in fresh and fight for the extra details that makes it so lovely.”

The initial process is the same for every job: space planning and layout

Gabrielle has developed this process and follows it for every job, no matter how large or small, traditional Georgian home or new build Passivhaus, and it is based around space planning and layout. She builds a picture by understanding her clients’ needs, finding out: where the furniture is going to go, how they are going to use each room, whether they have children or pets, whether they work from home, etc.

So the basis of any good design has to start with the layout, ie the way the space is going to be used, how people are going to move around the house, and what they need to keep in each room.

From there, a plan can be produced for the electrical, lighting, plumbing and heating layout. This is why it is essential to consult the interior designer at such an early stage, before the trades are involved, so that radiators aren’t already in the place where a TV or sofa needs to go!

Create mood boards to develop ideas

Once the practicalities of how the house is going to work, the room layouts, and plumbing and electrical plans are sorted, the next step is to think about how you want it to look.

Gabrielle often uses Pinterest to communicate with clients and create mood boards for each room. She creates concept boards which are linked to the Pinterest boards, and which are then linked to the actual products. For clients making their own purchases this provides a quick and easy way of shopping for their selected items.

Even if you’re not using an interior designer, Gabrielle recommends using Pinterest to create your own mood boards by finding inspirational images that you love and then start pulling out the key elements from that to make your board.

Gabrielle tends to use one big inspirational image that gives the feel of the room, and then surrounds it with the actual items that are going to be put into the room, ie a table, a lamp etc.

The whole house should have a united feel

That’s not to say it all needs to be painted the same colour, but running the same flooring through each floor can create that feeling for example.

In Ben’s house, Gabrielle noted how the snug needed to have a different feel, ie the winding down and having space for the evening, as opposed to the natural light of the large open spaces. For this they used a dramatically different paint colour to make it feel cosy and cocooning.

Don’t compromise on floors and doors

With any project it is important to set your budget and work out what you want to prioritise as early as possible. If the budget is going to be tight, Gabrielle recommends making sure that you have a good floor and doors – the bones of the house – so you have no regrets later on, even if that means having basic or little furniture to start with as that can always be built up over time.

In Ben’s house they chose a beautiful herringbone floor which becomes a feature in the open, uncluttered space.

“Working with fantastic trades will make a house”

Gabrielle suggested getting bespoke storage made, and Ben was fortunate in that the building company he used had very talented carpenters.

“What I love about bespoke joinery is it will never go out of fashion. If you do some really beautifully made but simple built-in shelves and cupboards, you need that storage anyway. Every family needs more storage than you can ever imagine, and cupboards are just the source of all happiness, so that’s great. And having them beautifully made, it just means you’ll never be bored of them.”

The right interior designer should add value to your project

Gabrielle stresses that it is important to choose an interior designer who you feel you can communicate with, and who understands you. There should also be a fee structure that you’re comfortable with, for defined chunks of work, and not just an open cheque book. It is something that needs to be budgeted for like every other part of the build.

The finishing touches can be equally fun and stressful

Gabrielle has joined Ben at the house for working out the finishing touches. She likens this time as being at the end of the marathon when everyone’s a bit tired. The house needs to have the final styling and dressing which is where the interior designer can give help and reinforcement. Together they have searched through Ben’s existing belongings to see if there is anything that, coming at it with fresh eyes, they might have forgotten about which actually will look wonderful in their new home. And then it’s just a case of deciding on the few more pieces needed to finish it off.

Some images taken before and after Gabrielle’s visit

Key tips:
- It’s your space – don’t be afraid to make unpopular decisions.
- If you’re being pressured into something because it’s easier for the build, or if in your heart it doesn’t really feel like you, then stick to your guns.
- Measure everything!
- Be confident in your tastes – you are the expert on you.
- Make sure you prepare: get your mood boards and layouts done before you even meet your builder for the first time. Including everything such your chosen doors and floors will mean a more accurate quote.
Find out more

Visit the website of Gabrielle Blackman

Follow Gabrielle on Twitter

Transcript

Download a transcript of the interview with Gabrielle Blackman.

Please connect with me
- Subscribe, rate and review the podcast in iTunes
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November 15, 2018
HPH211 : How does a local building contractor approach a competitive tender? – with Mark Feldman
Mark Feldman of MARS Building Ltd offers an insight into how he prices up potential new jobs (including when he’s invited into a tender process).

Interview with Mark Feldman

Mark Feldman runs his own construction company based in Hertfordshire. He began in the industry working as an apprentice carpenter and over the years had experience as a trainee site manager before returning to carpentry. He started his own business in the early 1990s and since then has built it up to be a limited company working on large extensions and new builds. His company, MARS Building Ltd, is the main contractor currently working on Ben’s Passivhaus self build.

A good standard of work comes at a premium

Mark likes to make sure that he has work scheduled for at least a six month period, and while they mostly do large extensions or new builds he might also take on a smaller job if it will fit in between other planned projects. Most of their jobs are won through recommendations from previous clients but they do also get approached as a result of their website, signs and vans.

Mark concedes that they may not be the cheapest contractor but they pride themselves on providing a good standard of work and feel this is reflected in the price.

Where jobs don’t come with a specification and they have to specify the job themselves from the drawings they aim to be as comprehensive and detailed as possible. Again this could account for a higher figure as other contractors might put in a lower price but be constantly adding additional works and extra items throughout the build process.

Items are specified by the architect but quantified by the builder

Mark has to rely on the fact that the architect and client have got the specification accurate and that those details match the drawings.

On receiving a tender package Mark would work through the drawings and specification and highlight if there is anything unusual so that he can research and get prices for those items. Then it is a case of working through and pricing the specification, then coming back to it a few days later and checking it through again.

As they haven’t been involved in a Passivhaus construction before, Mark has been careful with the pricing for Ben’s project and built in a bit of an allowance, not so much for risk, but to cover additional time and taping. The architect having broken everything down well means that they’ve been able to price for the individual items instead of having to guess at what they need to do to achieve the airtightness.

Mark does say that on other jobs, “sometimes architects can go too far with detail, and you end up pricing every little item down to the last screw almost. Everything gets a little bit added on to it, so it can make it quite a bit more expensive for the client if it’s too detailed for a specification.”

Tender submission prices may vary depending on existing workload

Some items on an architect’s specification will have a profit allowance next to them. For others Mark will cost for labour, materials and allow for a bit of profit on top. He will also put in a cost for site management, allowing for a day or two each week which covers the time he spends in discussion with architects, looking things up on drawings, general organisation and mediating between the trades.

Prices they submit will depend slightly on the circumstances at that time and how much work they already have lined up. Their most competitive prices are likely to be when they are running close to the end of a job and don’t have anything else lined up for when they finish.

Work on projects may overlap

Obviously a common question clients have is when the contractor might be available to start. Mark explains that the type of people they want to work for are those that want someone doing a decent job and as such might be prepared to wait until they are available.

There is often a transition period where jobs can overlap by a few weeks. It might mean starting on groundworks and brickwork on the next job while still finishing off their current project.

Communication tends to be more effective with an architect’s involvement

If they are working on a project where the architect has a continued involvement, then both the contractor and client will communicate via the architect.

In other projects the client may only employ an architect to produce drawings, and will oversee the works themselves. In this situation the contractor would be dealing directly with the client.

Mark says it is probably more efficient working with the architect but either process works well.

A combination of factors is causing higher tender submission prices

Ben was alarmed at the prices that came back on their tender submission and had wondered what might have been the cause. Mark suggests the following reasons:
- Labour costs have seen an increase recently
- A shortage of bricklayers has put their prices up
- The pound being weaker against the Euro has increased the price of imported goods
- The cost of insulation has dramatically risen over the last year – as much as 30%
- Timber and other items have also seen price rises.
Some of these prices have previously been absorbed by the contractor to try and win the work, but in order to maintain profit their prices are now creeping up.

Find out more

Visit the website of MARS Building Ltd

Transcript

Download a transcript of the interview with Mark Feldman.

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March 19, 2018
HPH206 : What solar PV panels should I get for my roof? – with Robert Flynn from Solarbarn
Robert Flynn from Solarbarn explains how to choose a solar array to suit your needs.

Interview with Robert Flynn

After spending 25 years in the IT industry, Robert had a change of career and set up Solarbarn. It was 2010 and at a time when the government introduced the feed-in tariff scheme which kick-started the whole industry.

While we have spoken on the podcast before about solar PV, we haven’t discussed what is required for the installation process. As we have been following Solarbarn’s installation at Buckinghamshire Passivhaus, our video case study in The Hub, we thought we would speak to Robert to give us an idea of what you’ll need to think about if you’re planning to install solar PVs.

Higher watt panels are only really needed on a small roof

How many panels you need will depend on your roof area, how much energy you want to produce, and how much you are prepared to pay.

According to Robert, you can’t really have too big a system. A large system may well produce more electricity than you need at a particular time, ie during the summer, but any surplus isn’t wasted as it is simply fed back into the distribution network to be used by others.

A standard solar panel is now 300 watts, but you can get 360 watt panels if you want to pay extra for a more efficient product. Robert suggests if you have a large roof you don’t need to pay for the more expensive panels, as you have the space to install more of the cheaper, 300 watt panels. He says the pricier 360 watt panels are really only necessary where you have a small roof and typical sized panels aren’t going to give you the power you need.

Roof pitch should be considered along with orientation

A south facing array will produce more killowatt hours in a year than an array pointing east or west, or south-east or south-west.

The shallower the pitch, the less of an issue orientation is. For example, with a shallow, 20 degree pitch, the panels are closer to pointing up in the air than at the horizon. A 45 degree pitch will make a difference as it is pointing more to the horizon. So a 45 degree pitch east/west will produce probably 25% less than the same array on a south facing roof.

In terms of consumption however, there can be benefits of going east/west. An east facing array will produce a little more in the morning, and a west facing array will produce a bit more in the afternoon than a south facing array. A south facing array will give you a bigger peak at midday, with perhaps less in the morning and afternoon.

Installations on new-builds are built “in-roof”

As Buckinghamshire Passivhaus is a new-build they have been able to do an in-roof installation. The solar panels are part of the roof so it ends up being tidier than a retrofit would be. It also means you save on the cost of roof tiles as these are not required under the panels.

The roof is built, felted and battened. At that stage Solarbarn would lay interlocking plastic flashing frames onto the battens which will ultimately hold the panels in place. The roofers return to tile the rest of the roof up to the flashing frames and making it watertight. The solar panels themselves aren’t put in place until the roofers have finished their work, to make sure they are protected and aren’t going to get damaged.

At this installation the clients are using a power optimiser solution. A power optimiser on each solar panel means that the panels can work independently of each other, so if one is shaded for example, it wouldn’t affect the output on any of the others, which on a traditional wired system can be an issue.

The distribution network operators need to be notified of systems up to 4 kilowatts after they have been installed. Anything over 4 kilowatts, as in the case of Buckinghamshire Passivhaus (7kW), needs to have their approval in advance as they need to be sure that the infrastructure is capable of taking the load when power is being injected back into the network.

The solar array is first tested on a sunny day to make sure there is enough power going into all the panels and optimisers. The inverter is switched on and is paired with the optimisers at a safe 1 volt DC. When it is fully up and running it will be up to around 400 volts DC.

The inverters get hot when producing a lot of power and eventually they will need replacing. They should last at least 5 years, and are usually guaranteed to last between 5 and 10 years. The inverter on the Buckinghamshire Passivhaus project is guaranteed for 12 years.

Buckinghamshire Passivhaus

Excess power can be diverted to an immersion heater

A lot of customers of PV systems now have an immersion heater diverter, because in a lot of cases PV systems will produce a lot of energy when you don’t need it. This channels any surplus power that would otherwise be exported, into your immersion heater.

Robert doesn’t feel that the economics of using batteries are quite right just yet, as they are expensive, don’t store quite enough and don’t last long enough. He does see a tipping point where improvement in battery technology plus escalating electricity prices will make batteries in solar PV installations a more feasible option.

They have future-proofed Buckinghamshire Passivhaus by laying cables ready for batteries and technology to measure how much of the power they use and how much they export. By being able to measure their actual consumption they will be better placed when it comes to buying a battery array that is right for their needs.

Ground solar arrays can be an option if space permits

A solar panel pointing to the sun produces as much electricity on a frame in the ground as it does on the roof of a house, so space permitting, a ground installation might be an option. To make it worthwhile there usually needs to be a meaningful sized array, and for that size you will need to obtain planning consent. They need to be kept secure from children and animals endangering themselves, and also from theft. Typically, the ground arrays Solarbarn install for clients tend to be for large country houses that have swimming pools and huge oil consumption.

Benefits are now more about self-consumption savings, rather than feed-in tariff payments

People are always keen to know how soon the system will start paying back. Previously the benefits to be had were in the feed-in tariff payments, but nowadays the benefits are more to do with self-consumption savings, ie “producing lots of electricity, using it yourself and therefore not having to buy it from the grid.”

“Generally, the people that were motivated purely on return on investment and how quickly they could get their money back are not those that install solar these days. The people that install solar these days are the people that want to do it because they know it’s the right thing to do. ”

The benefits of installing a solar PV system at the time of building a house are that it is zero VAT (because it is a new build) and there are no scaffolding costs because the scaffolding is usually there already. Most of the work they do on new builds is now just considered an extra cost at the time of construction that will provide a huge ongoing benefit thereafter.

The Hub

For in depth videos following the progress of Buckinghamshire Passivhaus and other case studies you can join our members only area of The Hub. As well as step-by-step courses, you will also be able to join in with our monthly progress calls where members can share news of their self build projects and get advice from guest experts.

Find out more

Visit the website of Solarbarn

Follow Solarbarn on Twitter

Transcript

Download a transcript of the interview with Robert Flynn.

Please connect with me
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February 8, 2018
HPH171 : An eco interior designer in the home – with Elina Grigoriou
Elina Grigoriou from Grigoriou Interiors talks about design, wellbeing and sustainability, and the role of interior designers.

Interview with Elina

Elina and her sister founded Grigoriou Interiors in 2010. Their vision is “to create interior spaces of beauty and function that look after people and our planet”. A strong theme of sustainability is used in their branding and website, to educate people on the concept of sustainable interiors and to attract like-minded clients.

Interior design is about understanding how space affects you

Interior design involves looking specifically at the spaces that fall within the floor slab, ceiling slab and external walls. Elina explains: “From the moment you step into a building until you come back out of it, everything you touch, everywhere you interact within that space is forming the interior and the way that has been intentionally designed to support your life.”

Design can influence how well you sleep or eat

Wellbeing is a big issue right now, and Elina finds that a lot of people don’t understand the effect their space has on them. It is often only when they start talking about how they behave in an interior that they slowly start to realise how the space is informing some of their behaviours, or may be stopping them from behaving in a certain way.

For example, the shape of a table will affect how people communicate. Are you sitting opposite each other at a square or rectangular table, or around one with no sides? Elina suggests that dinner with your in-laws might be nicer at a round table!

And patterns tend to help people to relax. Elina explains that we find them reassuring because we trust things that are repeated. Movement is associated with asymmetry, whereas a balanced style promotes calmness.

An interior designer can help create a living environment

There are different motivations for hiring an interior designer. Elina says some people feel they should hire one because they’re ‘supposed to’ or to ‘keep up with the Joneses’, adding the image-conscious association often linked with interior design is not helpful.

A better reason would be someone wanting to create a home that feels like a home, where they can entertain guests, work, and allow the space to affect them in a positive way.

Elina guides clients through a decision-making process to make choices they will be happy with. Interiors contribute to the relationships people have in their homes, and she wants that contribution to be a positive one.

We can better understand and re-use existing buildings

One step is to establish whether the original architecture assumed a particular ‘user journey’ from the moment you walk through the door. What kind of volumes and spatial proportions did the designer envisage for the interior spaces? If this hasn’t been considered, you can get quite structural: reforming spaces and opening or closing up floors.

Self-builds can get it right from the beginning

Unlike commercial and residential developments, which tend to be quite ‘vanilla’, the self-build ethos creates an opportunity to engage in the design process and make a home fit for purpose.

With new builds, Elina would recommend involving an interior designer at the earlier stages, when forming the architecture and considering what kind of lifestyle you want to enjoy in the building. That’s the time to start discussing the internal spaces, views, etc.

A detailed brief gives a clear basis to start from

Elina recalls a previous project where the husband wanted to have lovely conversations with his daughter in the living room. She comments that this is the kind of brief they can respond to and believes this is the right kind of objective for a home.

Grigoriou Interiors create what they call a user profile. Every question they ask of each client in the design process goes back to this profile, gradually informing how the space needs to be and documenting where they started from and why. Typical questions might include:
- What’s the geographical location like?
- What’s the typical climate?
- Is it an existing or new building?
- How many bedrooms do you want?
- Do you entertain at home?
- Do you work out at home?
- Do you like lots of fresh air in your interior?
- Do you like a lot of natural daylight coming in?
- How are you going to clean it?
- How long do you want to live there?
- Will you be there throughout the year?
- Do you want to rent it out?
Shorter purchasing cycles mean greater impact on the environment

Architects consider lifespans of 20-30 years or more, and these timeframes inform product and material decisions. However the average interior lifecycle is just five to ten years.

Elina says it falls to designers to ensure that what they specify is sustainable in the first place. Grigoriou Interiors talk with their clients to understand where the environmental impacts are going to happen from the client’s own behaviour in a space. For example, working from home may mean longer periods of heating and lighting. Establishing this in the brief, at the start, allows them to create a sustainable interior and suggest certain materials and layouts based on how the space will be used.

Beauty is very important when it comes to interiors

Elina explains that the perception of beauty is personal to everyone’s individual conditions at a point in time. So she has to work with clients to understand what they consider beautiful and what kind of look they want. Something minimalist? Or a bit of texture? Do they have some lovely crafts, perhaps from their travels?

Existing furniture may not be suitable for your new home

If you are moving to a different sized house, Elina suggests that some of the furniture you currently own – such as the dining table or soft seating – may be too big or small for the new interiors. Similar spaces may allow you to re-use existing furniture but it’s worth questioning which pieces may need to be recycled.

A new build, especially a passivhaus, presents an opportunity to minimise or even eliminate the introduction of pollutants. Emissions from materials and furniture will affect the quality of air inside the house so, for example, an existing sofa will likely have chemical foams. Elina is excited to see alternatives such as coconut fillers becoming available.

Deciding not to re-use doesn’t mean throwing away

If you can’t use some or all of your existing furniture, there are plenty of quick and easy ways to pass it on before moving. Freecycle and Preloved are just two websites and Elina says more options are emerging all the time.

Interior design advice doesn’t have to cost the earth

Even with a limited budget, it’s still possible to engage the services of an interior designer. The key is bringing them in at the right time to get their feedback on architectural proposals. Elina describes it as having them dip in for a day or two to review the proposals, give you some feedback and possibly pose some questions.

Find out more

Visit the website of Elina Grigoriou

Follow Grigoriou Interiors on Twitter

Transcript

Download a transcript of the interview with Elina Grigoriou

Please connect with me
- Subscribe, rate and review the podcast in iTunes
- Rate and review the podcast on Stitcher
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April 5, 2017
HPH126 : When is it right to demolish and rebuild? – with Simon Sturgis from Sturgis Carbon Profiling
Architect Simon Sturgis explains the circumstances around whether it’s best to retrofit or rebuild.

Interview with Simon Sturgis

For the last 8 or 9 years, Simon Sturgis has been looking at the issue of carbon in construction. This followed a period of doing a lot of retrofit work where it seemed that huge amounts of only partly used materials were wastefully being thrown away. They decided their challenge was to be whether this could be quantified, which developed into the idea of carbon valuing: a valuation using carbon as a currency of sustainability.

“To make anything takes up energy, and depending on where it’s made, it determines the sort of energy”

People were already familiar with measuring energy usage in buildings, but Simon explains they were keen to come up with something equally familiar that related to materials, and the problems around the negative aspects of how they’re made.

Where the material is made will determine the kind of energy that is used to make it. For example in Norway it would probably have been made using hydroelectric energy, however in the UK it would more likely have been using gas and oil.

“So it’s really understanding that and trying to redirect our ability to make things away from, if you like, damaging carbon intensive technologies.”

Ensure any new building has the ability to be recycled and re-used

Simon discusses what you should consider if you’re thinking about demolishing a run-down old building to replace it with something new. He says that if it’s falling apart then it’s probably better to take it down and dispose of and recycle it as best you can, but build something in its place that fulfills the durability factor that the previous building didn’t have.

In your new building, consider whether it is capable of easy recycling or adaptability and re-use. If you’re constructing it from brick then you might be confident it will last a couple of hundred years, but if you’re using timber you might say that it’s not going to last as long but at least it can be adapted, re-used or moved to do other sorts of things with it.

A change of mind-set is needed

People need to change their way of thinking to a ‘circular economy’. Simon explains that in the City of London office buildings have an average life expectancy of around 17 or 18 years, which clearly is going to have a huge carbon investment. He believes that there should be planning at the outset for a building’s eventual disposal, and with the expectation that when you’ve finished with the building it can be taken apart and the elements distributed to be re-used in other buildings, not necessarily in the same place.

If you intend to re-use things you need to consider right at the beginning how they will be put together, in order to make it possible to dismantle and re-use them, i.e. using a lime mortar that can easily be removed from bricks, instead of cement mortar.

Simon uses the example of a two-storey office/shed type building where, because of its steel bolt and aluminium construction, they were able to help a client to take it apart, move it to a more suitable location, and re-build it, while tidying it up as they went along. They were able to re-use around 70% of the materials and along with significant carbon benefits, it cost 25%-30% less than a new building of the same size.

The cost of recycled products can be prohibitive

This may seem counterintuitive at a glance, but it’s cheaper to buy new bricks than old ones. Largely this comes down to the cost of cleaning up the bricks from a dismantled building is high.

However Simon suggests that if the process of cleaning the bricks was paid for through social value, for example being done by people who might otherwise be in prison, then not only could the recycled brick be bought for the same price as a new one, but you’re also contributing to social issues and turning the demolition process into a positive one.

You can’t necessarily demolish any building

If thinking about demolition, consider the following:
- Whether it has listed building consent or is in a conservation area.
- Possible health and safety issues if the building you’re demolishing is next to a sensitive site or railway line, etc.
- Whether there are issues to be resolved due to party walls.
A high standard of retrofit may have the lowest carbon impact

Sturgis Carbon Profiling produced an article looking at carbon emissions over a period of time in 3 different scenarios.

The first scenario was the carbon cost of maintaining an existing Victorian terraced house – principally in heating and energy use.

The second scenario looked at taking that same Victorian terraced house and upgrading it to a high standard. While that does take a lot of material going into the building, it does make a huge difference to the performance and requirement for heating.

The third scenario looked at building an entirely new Passivhaus, with its high levels of insulation and airtightness.

Their analysis considered both the carbon emissions from the materials used, together with carbon emissions from day-to-day use. What they found was that, based over a 60 year period, it was better to retrofit the existing terraced house to a high standard than it was to build the new terraced house. The reason for this is because there is so much energy used in producing bricks and other materials for the new build.

“So it’s not necessarily the case to say you should demolish Victorian buildings if you want to get a highly efficient carbon outcome. You need to make them work better… And in a sense we’re doing society a good service by re-using things rather than flattening them.”

Transcript

Download a transcript of the interview with Simon Sturgis.

Find out more

Visit the website of Sturgis Carbon Profiling

Follow Sturgis Carbon Profiling on Twitter

The Hub update

The Hub is an extra learning and networking resource, tying together everything we’ve learnt from our podcasts, together with extra information and interviews. We have video case studies and currently have a number of short videos showing the different stages of the Long Barrow Passivhaus project that we’ve been following. We’ll also soon be confirming details of our second case study.

Each month we’re also adding a new module which lays out different parts of the self-build process in simple steps.

Our current beta launch price of £45-a-year, which is a lock-in price that you will keep every time you renew, is going to expire at 9pm GMT on 30th April 2016. After that the price will go up to £99-a-year. Find out more.

Please connect with me
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April 27, 2016
HPH099 : My New Developer House has No Loft Insulation – with Luke Mahon
It has been almost a year since Luke Mahon took ownership of a new-build developer house, which he soon discovered lacked insulation! He talks us through his experience and the ongoing battle to get the house completed.

The Property Location and Size Were Ideal

The development was in their target area between Heathrow Airport and Reading town centre, whilst also being close to countryside. After being impressed by a show home on a similar development and hearing good reviews from his wife’s grandparents who had been very pleased with their own Taylor Wimpey home, they decided to purchase the property.

Within a Month the House Seemed Unreasonably Cold and Draughty

The large master bedroom in the eaves had been one of the reasons Luke was drawn to the house, but by the October (within a month of moving in) they were going to bed shivering from the cold and the breezes in the room. On investigating an area of the loft, Luke discovered there was no insulation!

Uninsulated loft space

The developer agreed to rectify this but Luke was insistent that even after insulation was added to the loft space it was still uncomfortably cold and was convinced it was still lacking in insulation. Luke describes how after much arguing they agreed to cut holes in the walls – and sure enough, found no insulation! After they stuffed some insulation in there and patched up the holes, Luke was desperate to have the work completed before his family arrived at his house for Christmas, and says on the last working day before Christmas he was given paint and a roller to paint the walls himself as all the painters had gone home.

The Snagging List Eventually Contained Over 400 Items

Initially the list was at around 150 items, but over time they discovered many more. While some were very minor and things they would have expected in a new house, others were significant. The list included: cracks on walls, plasterboard not properly matching, toilets in the wrong place, wrong tiles being laid, windows at an angle, doors needing to be replaced, walls needing to be rebuilt as they had been erected incorrectly / at the wrong angle / wobbly because they didn’t have enough studs in them, air bricks too low to the ground or even underground etc.

Luke says he had to fight for this door to be straightened

Luke Used His Marketing Experience to Get His Voice Heard

Luke says he was tired of repair works not progressing and his calls for action being constantly ignored. As they live close to the show home he put up posters in his window to alert potential purchasers. This caught the developer’s attention and Luke says for a period of a few weeks there was communication and numerous promises but that he grew frustrated by this only resulting in minor things being attended to, at a slow pace and a poor standard of work.

After trying unsuccessfully to resolve the issues through the on-site customer services representative, regional office and head office, Luke started his @MyHouseSucks Twitter account. He feels that it is only because of this and the media coverage it generated that he has been able to make any progress.

Poster in the window of Luke’s house

His House Was Not An ‘Isolated Incident’

Luke says he had been told by the developer that the other houses had been checked and didn’t suffer from a lack of insulation and that his house was an isolated incident. Through his Twitter account however Luke discovered his neighbours in the development’s first phase were having similar problems and claims that, despite knowing this, they continued to build further houses on the development with no insulation. Tweets he received from owners of homes built by other developers, led him to believe that the “isolated incident” tactic is commonly used to discourage people from talking to their neighbours and uncovering the extent of deficiencies.

Insulation going into the roof space

A Thermal Survey Was Conducted

It had not been possible to have a survey of the property before completion of the purchase. Luke says he had requested one but that access was refused as it was an active building site. He pushed later for a thermal survey which uncovered the extent of the problems.

Rectification works at the house have involved 14 weeks of workmen on site, a further 4 weeks where they had to move into alternative accommodation, and are currently going through another 4 weeks of backfilled soil being removed. In total, Luke estimates these works have probably taken longer than it took to build the house!

Thermal image after some initial rectification works had taken place

Luke Questions the Role of the National House Building Council

These buildings aren’t signed off by the local council building regulations department, but by the NHBC (National House-Building Council). Upon contacting the NHBC, Luke was told they would have noted the lack of insulation and asked the builder (verbally) to resolve the issue.

Luke is shocked, that not only did they sign off his property which clearly didn’t meet building regulations, but also those of his neighbours, and all of those that he says the developer knowingly built without insulation after discovering the omission in his own house!

With the NHBC being funded by the house builders, Luke asks of the situation:

“These large companies who snap up all the land, build these sub-standard properties, get them signed off by a body that they’re paying for to sign them off, that don’t meet building regulations and that’s all fine?”

A Happy Ending?

Almost a year after moving in Luke says they are down to around a final 10 items on the snagging list so he can see an end in sight.

“I’m so far beyond angry now. I was angry, probably a few months ago. I’m beyond that. I’m dispassionate about it now because it’s taken so long, it’s become part of my life.”

Despite that, Luke foresees that once the works are completed he and his wife will be happy in their home. The reasons why they chose the house will prevail – ie the space, the light, the size of the garden, it’s location backing onto natural parkland.

“And actually throughout all this kind of arduous year of hell, we’ve really built a really nice community here within this first phase because we’ve all got to know each other as neighbours and it’s a really great community of people here. So because of that it actually does feel like home.”

Find Out More

Follow Luke Mahon on Twitter

Transcript

Download a transcript of the interview with Luke Mahon.

Please Connect With Me
- Subscribe, rate and review the podcast in iTunes
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September 16, 2015
One week until the podcast launches!

The clock is ticking down to the first episode of the House Planning Help Podcast. It’s one week today that we launch with great guests lined up including eminent physicist Dr Wolfgang Feist, Pat Wilkinson from Touchwood Homes, Martin Evans from The Malthouse Consultancy, Simon Lewis from RW Armstrong, Adam Dadeby from Passivhaus Homes, and of course lots more. It’ll be available to download from iTunes but if you want to make sure you don’t miss it, sign up for the mailing list using the form to the right.

Check out the trailer by clicking here.

July 25, 2012