Tag: Building an energy efficient home

HPH277 : The importance of building performance evaluation – with Professor Fionn Stevenson

Professor Fionn Stevenson explains why building performance monitoring and post-occupancy evaluation should be mandatory on new homes.

Interview with Fionn Stevenson

Having spent eight years in practice as a chartered architect, Fionn was finding that the housing wasn’t performing as well as she had designed it to do. This led to her interest in building performance and eventually she became a researcher and academic in the subject, as Professor at University of Sheffield – School of Architecture. She has now been involved in building performance for over 20 years.

Six simple action points in a light touch review

A light touch post-occupancy evaluation involves going into a home to check how well it’s performing against its design intentions.

The first step is for the expert to spend around half a day studying the original drawings and specifications for the project, as these are what will be checked against during a tour of the home. They provide the baseline of what is supposed to have been done.

This is followed by a half day tour of the home with the occupants, plus the designer and contractor. The occupants will explain about living in the house for the evaluator to see what’s going on and check that against the original design intentions.

The occupants will also complete a simple two-page survey which provides a lot of further information.

A half day thermographic imaging survey is then carried out to see how the fabric of the building is really working.

Next is looking at how the building is performing in terms of energy used and water consumption. This can be done at the simplest level of looking at utility bills, or recorded through smart metres.

And finally, there will be a spot check where, during the half day tour, the evaluator will use a hand-held 4-in-1 metre to check on the room temperatures, plus levels of light, sound and humidity.

UK housing doesn’t perform as it should

Given the nature of unique sites and being very contextual, Fionn says UK housing does not perform as it is expected to do. She says that research shows that on average new homes in the UK use at least twice the amount of energy they’re supposed to use. That can be down to the design but also the quality of construction.

Another concern is the indoor air quality results, with high levels of carbon dioxide build-up, low-level toxins from off-gassing of new materials, and air fresheners which are supposed to make the air quality better but can actually make it worse. New homes need to have good ventilation strategies, but often they have been poorly designed, constructed or commissioned.

Building evaluation should be mandatory

As well as post-occupancy evaluation, there can also be building performance evaluation. This involves starting the evaluation process from as early as developing the brief, and right through the complete cycle of the project.

Fionn says it’s amazing that there is no mandatory requirement to carry out post-occupancy or building performance evaluations, and that is something she is lobbying to get changed. The RIBA is now producing new guidance and in the future is looking to mandate its practitioners to make it a part of their service. But there’s no mandatory requirement to carry it out as currently it requires consent from the client.

“If it was mandatory there would be an automatic performance feedback loop because people would have to automatically report what is actually going on in the housing. That reporting would then go into databases and everyone could see what was going on.”

Fionn has worked with a number of volume housebuilders, and says that although they carry out extensive customer satisfaction surveys to see how well their buildings are performing, they are not asking the right questions. They don’t drill down into why the house is or isn’t working for them, and this is because they haven’t had to be accountable for the performance in mandatory terms.

“What they’re interested in is selling the home. They’re not as interested in how well the home is performing once they’ve sold it. They just want to make sure the customer is happy, they want to make sure that they get their NHBC scorecard with the highest number of stars, and that’s all about reputation. And their reputation rests on the initial customer satisfaction survey, not the overall performance of their homes.”

There needs to be databases of results

Fionn mentions the Building Performance Network as being a group of organisations and experts who are spearheading the drive to make building performance evaluation and post-occupancy evaluation routine. They are collecting data and setting up a UK database.

And Fionn says that this is what needs to be happening. She says there should be two databases: one a private one where people can access their own data, and the other a public one with anonymised results to give a national picture of how everyone is doing and enable people to benchmark and compare against others.

A culture shift is required

Fionn explains that at the moment the process for architects and clients is “let’s design a home.” In fact what it should be, is “let’s design and evaluate the performance of a home.” The majority of architects don’t go back to really evaluate how well their buildings are performing. Fionn says the key message she is trying to get across in her book is that this should be routine.

Be energy sufficient, not just energy efficient

Fionn is in the process of starting her own self build project. But rather than design it herself, as she has been out of practice working as an academic for so long now, she is using the networks she has built up to find the best team to deliver her project.

She has prepared her brief and will be looking for people that will champion her wants, needs and follow the details of the brief throughout.

A fabric first approach will be used to make sure the house is properly insulated, airtight and ventilated. With that is the importance of getting the size of the home right. She explains that it’s not enough just to be energy efficient, but we need to think about whether we are being energy sufficient. In other words, having the house optimally sized and not any larger than it needs to be.

“There’s a bit of a misnomer about zero-carbon because of course you can make your home automatically zero-carbon if you go onto a renewable energy supplier. But that doesn’t mean your home is actually being very good for the environment. We’ve got very large self-built homes that are claiming to be exceptionally low energy or carbon zero but actually the embodied energy, the amount of materials that are being used in them is huge.”

Keep the buildings simple

Fionn says that there is a temptation with self build to have the house of your dreams and put in a lot of unnecessary kit. Her own research has found that often in homes that were using heat pumps together with PV and solar-thermal, often they were contradicting each other as they weren’t designed to work together. Also, solar renewable energy installations hadn’t been installed correctly or on the wrong orientation, meaning they weren’t performing as they had been designed to do.

Another thing the post-occupancy evaluations have thrown up, is how important it is for any mechanical ventilation system to be well designed, brilliantly constructed and have the minimum duct runs possible. It must have vents perfectly positioned and be ergonomically designed in a way that is accessible for the occupant to interact with it.

There isn’t enough data to help self-builders with decision-making

Fionn explains that we’re still flying blind with a lot of modern building systems as there just isn’t enough data from post-occupancy evaluations to see how well they perform. Being laboratory tested can only do so much.

“Who is going out there, outside of the laboratories, into the homes with the thermal imaging camera, doing the walkaround, seeing the little bits of mould that are appearing in the corners? If we move on to service systems, we’ve got loads of mechanical ventilation heat recovery systems. But who went out there and actually asked the occupants whether they can use them? That’s been the issue, that it is difficult for self-builders to choose systems and know that those systems have been not just rigorously tested in the laboratory where the products are developed but that they’d been systematically tested around the country in every city, in every town, as a routine part of post-occupancy evaluation which is then fed back into the industry. This is exactly why the housing industry performs so badly.”

An investment worth making

Fionn stresses that you should be alert throughout the whole design, build and occupancy process, but there are key points where attention particularly should be paid.

The first is at the outset of the project, where post-occupancy evaluation is included in the brief, and budget allocated for it. Typically it might cost around £5,000 for a light touch post-occupancy evaluation, but it could be saving you tens of thousands in identifying hidden risks and defects.

Other benefits are that you’re also future-proofing for climate changes, ensuring there won’t be overheating as UK summers continue to get hotter, and also improving health issues with better air quality.

The second critical stage is the commissioning of the home. When the services, heating and ventilation systems are commissioned is a crucial time for there to be an independent evaluator checking whether they have been set up properly, to avoid a lot of problems down the line.

Find out more

Follow Fionn Stevenson on Twitter

Check out Fionn’s book:

Transcript

Download a transcript of the interview with Fionn Stevenson.

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February 12, 2020

HPH182 : Extracting energy from watercourses by generating electricity and extracting heat – with Justin Broadbent from ISO Energy

Justin Broadbent from ISO Energy explains the options available for extracting energy from water on your plot of land.

Interview with Justin Broadbent

It’s our second chat with Justin Broadbent who is the chairman and founder of ISO Energy, a renewable energy installer. Last time he explained what a ground source heat pump is.

Water gives more energy than wind because of its density

There is a long history of using watercourses to drive mechanical objects in the UK. Although grain grinding was wind-powered, the mills of the early Industrial Revolution were driven by water because of the amount of power in it.

Extracting heat from water can be simple and efficient

If you have a small stream running through your garden, the simplest and most worthwhile thing you can do is extract energy in the form of heat. Justin says, “If you have the right spot and you have the right watercourse, then it is fantastic.”

Any water can be used for energy extraction

A large pond can be used for extracting heat; the amount of energy depends on the size of the pond and the heat load required. A flowing river has a constant temperature of 7 to 12 degrees, and a pond can get much warmer.

If there’s a flow in and out of the pond, the energy is effectively being replaced all the time. With a stream, the energy is quickly replaced so more heat can be extracted.

Choose the correct heat extraction device

In a pond with fairly slow running water, Justin would install a simple mechanism that extracts heat using coils of plastic pipe.

In slightly flowing water he would use ‘Energy Blades’. These banks of stainless steel ‘radiators’ extract an enormous amount of energy. Justin explains, “Almost whatever you take out, as long as you don’t actually freeze the water, two seconds later, there’s new fresh water coming down the stream.” Such systems can be scaled up to extract hundreds of thousands of kilowatt-hours a year, by putting in banks of multiple radiators.

You may need planning permission

In an area of outstanding natural beauty you must obtain planning permission for works like these. Additionally, Justin says you would need permission from the Environment Agency to dam a river or stream, but not if you wanted to put an Energy Blade in the water as it’s easily removable.

Expertise is necessary but installation is relatively straightforward

Justin says that extracting heat from water is cheaper and more efficient than from the ground, which is not as straightforward. He says it’s worth employing professionals but essentially, if you’re fortunate enough to have a stream, you can easily install an Energy Blade for two to three thousand pounds. To do the same in the ground, he estimates a cost of five or six thousand pounds.

Heat extraction doesn’t have to be hugely invasive

Some of Justin’s clients make a feature of how they’re heating their house, for example diverting part of their stream, and adding a canal and viewing walkway. But you can simply put the energy blade in the stream and dig a small trench back to your heat pump.

Hydroelectric generation ideally needs both volume and flow of water

To generate electricity from water, you need the water to drop enough between the top and bottom of the stream. The greater this ‘flow’ or ‘head’, the more power you can generate. Justin summarises, “In an ideal world you have head and volume and then you can build a traditional turbine. If you don’t have the head, then you have to have even more volume.”

Traditional hydro systems are built near big mountain rivers in places like the Alps, Scotland and Wales. The right features are not easily found in the south of England and where they do exist you’d be unlikely to get planning permission.

If you can’t have a turbine, look for old water mills

In Southern England, generating electricity from water is rare. However, Justin’s company has converted several mills where turbines can’t be used but the volume in the hill stream is sufficient to drive an ‘Archimedes Screw’, where the flow of water turns an electrical generator.

The same feed-in tariff for photovoltaic cells applies to an Archimedes Screw

Some of these systems generate a constant 15 to 20 kilowatts of electricity an hour. As this is far more than a single house needs, you can sell the surplus back to the electricity companies. Justin adds, “If you have photovoltaic panels on your roof, they might produce a few kilowatts. Well, an Archimedes Screw should be able to generate tens of kilowatts. Much more efficient.”

These are low maintenance, robust systems

Energy blades are fairly static and require very little maintenance. As they are stainless steel they don’t rust and have quite a long lifecycle. Furthermore, they are protected by guards built on the front.

Likewise, Archimedes screw systems are heavy but fairly basic, just needing the bearings replaced when they eventually go and some maintenance of the gearbox.

Environmental considerations can add costs

Heat extraction in streams won’t affect wildlife, as the amount of energy taken out is so small in relation to the volumes involved. A pond cooling may affect wildlife slightly, but Justin is reassured that those species survive lower temperatures in Scotland.

Justin explains that you can’t block a stream completely to use the power of the water. One common, though costly, method to ensure that fish, eels and animals can get by is to use a ‘fish pass’. A maze of gradual drops allows fish to swim upstream, avoiding the mechanism.

You get less return on investment with a smaller system

There’s not much difference in the cost of a small system producing five kilowatts and one giving 10 to 20 kilowatts of energy, because of the costs of getting permissions, civil engineering and manufacturing. Justin explains that his company rarely works on systems that are producing less than 20 kilowatts. “Suddenly you’ve found that it’s all going to cost £150,000 and you’re only going to make £5,000 a year out of it. It doesn’t pay back.”

Item	Approximate Cost
5 kilowatt Archimedes Screw	£15,000
20 kilowatt Archimedes Screw	£60,000
Civil engineering	£20,000
Fish pass	£30,000
Planning permission / consultant’s time	£40,000

It’s worth investigating how to use any water source on your plot

You may be able to generate electricity or heat, or even both, from water on your land.

With current government incentives (those for generating electricity normally last 20 years, and about seven years for heat), Justin calculates you can get your money back on a heat system within three to five years, followed by hugely reduced running costs.

And you might even be able to get government incentives to support the construction of the system. “So, it’s definitely worth doing,” Justin says, “So long as the government grants are out there.”

Find out more

Visit the website of ISO Energy

Follow ISO Energy on Twitter

Transcript

Download a transcript of the interview with Justin Broadbent

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June 22, 2017

HPH175 : From briefing to planning – with Chris Parsons
Interview with Chris Parsons

Ben reviews the journey from briefing to planning stage for his own self-build project, with their architect Chris Parsons from Parsons & Whittley.

Initial sketches seek to reconcile constraints and opportunities

After their briefing session with Ben & Kay, Parsons & Whittley set about sketching some ideas to see how the whole brief could come together. Constraints (such as where the building can be situated, the orientation etc.) and opportunities (for example nice views) needed to be incorporated into the designs.

The firm uses SketchUp for initial designs through to the planning stage; this 3-D software enables them to play with shapes to try to find a form that works.

When you add materials, the building takes on a different identity

Chris explains it was a deliberate decision to omit materials from the first sketches sent to Ben & Kay, as materials can have a significant impact on how a building looks and the first task was to isolate the form.

They had some ideas about materials when producing the first sketches, but when they put them onto the model in SketchUp, Chris felt it might be a step too far at that point to try and get commitment on material choices.

Involving planners early on can inform the end design

After a bit of feedback from Ben & Kay about the form and floor layout, Parsons & Whittley submitted updated designs. The planners flagged a potential issue with the height of the building, which could affect the neighbour.

As Chris puts it, “There’s no such thing really as a right to a view and there’s not much in terms of a right to light. However, the planners aren’t going to approve something that seriously impacts on the amenity and the enjoyment of the neighbour.”

Therefore both neighbours and the surrounding area have to be kept in mind during the design phase. The following measures were taken for Ben & Kay’s house to address the issue:
- Ridge height reduced
- Small catslide element put across the lesser status rooms at the back
- House repositioned slightly further away from neighbour than in the earlier consent
Specific materials may have architectural implications

Chris recalls that trying to find the right material balance for what they were trying to achieve required some ‘toing and froing’. Brick and barn aesthetics were discussed, along with black weatherboard, but Ben & Key felt this to be too strong. A rendered look was more appealing, but perhaps not for the whole building.

This thinking, along with trying to avoid overlooking the neighbour, meant different materials were considered for different elements and started to introduce a degree of complexity that neither party really wanted. However it was a valuable process that resulted in a return to a simpler form but with a provision to protect the neighbour’s privacy.

Understand the local vernacular in terms of materials

Chris explains that once form and scale have been agreed, the following questions will help work out what finishes will be applied to the outside:
- What are appropriate materials for the location and setting?
- What does the client like?
- Are there issues around maintenance and longevity of certain materials?
It’s also time to decide how the house will be built, using timber frame or masonry, for example. Kay expressed an interest in a soft lime rendered finish and to do that properly, Chris felt it would be easiest and most cost-effective to apply that to a masonry external skin.

It’ll be a whole lot easier if you avoid the green belt

Parsons & Whittley eventually managed to track down a copy of the green belt area, which they then transferred onto their plans. This showed the planners they weren’t straying into the green belt, only coming up to the edge of it so that the house would be as far away from the neighbour as possible and maximise the amount of private garden for Ben & Kay.

Anticipate what planners are going to ask you

Chris’s advice is to think carefully about what you’ll need to demonstrate within all of the documents being submitted as part of a planning application.

SketchUp allows them to position the house “in the real world”, so they did quite a lot of work in terms of a ‘shadow study’ for Ben & Kay’s project. By setting a date and time within the software, they can see where the shadows are likely to fall and demonstrate there’d be no overshadowing of the neighbour.

They also developed a cross-section that showed i) the existing consent, ii) all previous consents on the site, and iii) what was now being proposed, for comparison and to dispel concerns of overshadowing.

Lastly, they ran a straightforward PHPP model (with some assumptions at this stage) and submitted the verification sheet to the planners to support the argument that this will be a Passivhaus.

A section 73 application to alter existing consent may be appropriate

You don’t always need to submit a brand new planning application if consent already exists. In Ben & Kay’s case, Chris simply wanted to vary the approved drawings.

This was a tactical decision given the proximity of the site to the green belt. As the principle of building on it has already been established, the section 73 application allows the planning officer to determine if this dwelling they’re now presented with is acceptable in planning terms.

Changes in legislation require planning departments to list the drawings that they’ve approved, which makes it easier to pursue this route of seeking to change approved drawings rather than revisiting the whole policy of ‘can I have a house there?’.

It’s not always a straightforward ‘yes’ or ‘no’ planning decision

Planners are required to make a decision within eight weeks from the date of validation. Chris says that most planning authorities get about 90–95% of decisions through in that period of time. If decisions need to go to a committee, then the timeframe might be extended but only with permission. If they can’t make a decision within eight weeks, applicants have the option to appeal to the Secretary of State against non-determination. However this isn’t a process Chris would recommend as it would likely take at least six months to get through it.

The outcome will be yes or no but might be a yes with conditions, some of which the applicant isn’t happy about. If the planners were to refuse the section 73 application submitted on behalf of Ben & Kay, they could only do so on planning grounds. Parsons & Whittley would look at what those planning grounds were and advise on the best way to proceed. This may be simply amending the design to satisfy the planner’s concerns and re-submitting, which within 12 months for the same type of application does not carry a fee.

The appeal route would remain a last resort. However, Chris argues it shouldn’t get to that point as a good architect will stay in contact with the officer during the eight-week review period to ascertain if there are any objections that can be resolved before any decision is made.

Find out more

Visit the website of Parsons + Whittley

Follow Parsons + Whittley on Twitter

Transcript

Download a transcript of the interview with Chris Parsons

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May 3, 2017
HPH162 : Briefing our architect for our house build
Ben and Kay Adam-Smith sit down with Chris Parsons from Parsons + Whittley to run through the brief for their self build project.

Discussing our self build project brief

This podcast is slightly different to normal because we’re eavesdropping on a meeting! And this is no ordinary meeting: it’s the initial briefing session with our Passivhaus architecture specialists, Parsons + Whittley. Chris and John sat down with us.

So, we hear a few extracts from that meeting.

Items on the agenda
- Our accommodation requirements
- Budget
- Stylistic preferences
- Constraints (including planning history)
There’s no such word as ‘no’ when compiling the brief

As Kay reads through our list of accommodation requirements, she gets to the snug room.

Kay says: “I’d really love a fireplace but I’m told I can’t have a fireplace!”

Chris responds: “There’s no such thing as can’t. Everyone recognises the emotional attachment to a heat source. It can be done. We have done wood-burners, for example. You need a really good one because you need to control the air supply etcetera.”

However, Chris goes on to explain that one of the underlying benefits of a Passivhaus is that they are ‘innately comfortable’. With the indoor environment so pleasant, you don’t come into the house and shiver . . . and so there’s no need to sit around a heat source.

How could we build in flexibility?

Where we currently live (with a floor area of 60 square metres) has been a squeeze as our family has grown. This has meant we can no longer have guests to stay unless they are prepared to brave the sofa.

So in our new house we’d love some flexibility of how we might accommodate more guests at Christmas, for example, without building five guest rooms!

We are keen to use all the space every day (or get as close to this mantra as we possibly can); and let rooms do double duty when we have people to stay.

Creating ample storage space

With an attic brimming with ‘stuff’ we highlight storage as being something that’s important in the new house.

Accustomed to using our attic space, we ask Chris whether building a warm roof (also known as a Cathedral roof) is the best option.

Chris replies: “I would rather keep everything within a simple thermal envelope because that just makes it easier to build, cheaper to build, more efficient, more effective. To disrupt that for storage . . . maybe there are better options.”

Having all of our possessions within the house would also make them easier to access. Plus we might be more ruthless in accessing whether we really need everything (or can have a clear-out).

Where is the balance between traditional and modern?

While my aesthetic tastes have broadened since launching the podcast, Kay’s favourite buildings are period properties.

That said, we both like modern interiors – open plan living, big windows that bring in lots of light, etc.

So while the external appearance matters to me it is not as important as designing a house that all the family loves. So, how do we do this?

Chris explains: “It’s about distilling what it is that you like about that [the buildings you love] and trying to make sure we deliver it. We might be a little bit subtle about how we make sure it’s still a modern home, in terms of the facilities, the way that you use it, the spaces that are available.”

Chris continues: “So they do present conflicts, because the kind of stuff you like [old cottages etc.] is driven from an architectural vernacular which is quite limiting in terms of the spaces available. It was basically driven by how big a tree can you find. Because if you’re going to have a rafter or beam you’re limited by the size you can get.”

Building with ‘natural’ materials will have a cost impact

Kay and I are both drawn to materials like straw bales, lime render, clay plaster, thatched roofs, etc.

Upon hearing our list Chris wanted to chip in: “There’s a sort of sliding scale of really super-duper, sustainable materials which is almost diametrically opposed to the costs.”

“The most efficient material is probably not the nicest for the planet but will give us the best cost output. So somewhere on the spectrum I need to understand where you are sitting.”

We decided that we were tending more towards the ‘ecological’ materials but probably not going to the extreme.

Next steps

After our meeting (which was probably closer to 2 hours rather than the 30-minute podcast), Chris and John went to look at the plot.

Now they have all the information they need to create some sketches (either hand-drawn or in SketchUp).

Find out more

Visit the website of Parsons + Whittley

Follow on Chris Parsons on Twitter

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February 2, 2017
HPH143 : Why I couldn’t build a house in 4 years – with Ben Adam-Smith
Ben Adam-Smith reviews the key decisions that may have led to failing to build an energy-efficient home within his desired 4-year timeframe.

The story

Watch this video to get a refresher of the challenge Ben set himself in August 2016.

Five decisions that could have impacted on the progress

1. Spending two years doing research before starting my land search

2. Not being prepared to relocate to available plots

3. Not being prepared (or sometimes able) to pay over the odds

4. Not managing to enlist a homebuilding coach (architect/builder)

5. Not taking risks beyond a certain point

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August 23, 2016
HPH079 : How Ventilation in the Home Has Evolved – with Mark Chesney from Beam
Mark Chesney from Beam Vacuum & Ventilation explains how houses have become increasingly airtight and why this has had a significant impact on energy efficiency. He also shares why having a good ventilation strategy is so important.

Interview with Mark Chesney

Mark Chesney is the Installation and Services Manager at Beam. For 15 years the company has been fitting ventilation products into new and existing homes as part of energy saving measures and to provide clean indoor air.

Ventilation Products are for All Homes

Mark believes this is applicable whether the homes are decades old or airtight new builds.

There are Three Parts of a Building That Need Ventilation
- The living space
- The structure
- Where there might be combustible appliances, such as fires and stoves etc.
Mechanical Ventilation is Required on More Airtight Buildings

Historically, mechanical ventilation hasn’t been required as buildings have had so much natural leakage within the frame of the house. With the ever rising costs of fuel to heat homes, far more consideration is being given to creating more airtight dwellings, and with this is the need for mechanical ventilation to allow the people within the home to breathe more easily and allow for better air change.

The Cheapest Way to Ventilate a Building is to Open the Windows!

Obviously the drawback of natural leakage and opening windows to ventilate buildings is that you can’t control the cold ingress from outside or the heat loss to the outside.

This method of natural ventilation progressed to trickle vents and independent extract fans to more modern mechanical extract systems and ultimately the Mechanical Ventilation with Heat Recovery (MVHR) systems that are now recognised as an essential part of an airtight home.

The Number of Air Changes Per Hour Will Impact on the Building’s Ability to Retain Heat

If you were to ventilate a domestic home with 4 air changes per hour you would struggle to retain heat within the home. The recognised rate for a new build would be closer to just less than half an air change per hour. A Passivhaus is even less at .3 changes per hour.

Setting a new home to have one air change every two hours will greatly reduce or eliminate condensation and mould, and provide a fresh air climate. Most of the products will also filter the air to some degree.

The Airtightness of the Home Will Help Determine the System to Use

Things to consider when choosing a system are, the number of people living in the home, its airtightness, and whether it is well insulated enough that it warrants an MVHR system. Sometimes a simpler system will be an approved alternative in an older and less airtight retrofit.

The heat within a Passivhaus equipped with MVHR system will be retained much more easily than in a traditional dwelling, which even with a low air permeability rating and high levels of insulation, is still going to need a primary heat source.

A Central Vacuum System is Independent of a Ventilation System

At Beam, they provide both central vacuum systems and ventilation systems which, while being standalone products, both have the combined aim of providing cleaner air and a better indoor climate for everybody, with particular benefits to those suffering from asthma or allergies.

The central vacuum system works by drawing out dust through special wall sockets, along a lightweight hose and out via a motor located in a non-living area of the house.

Airtightness is Now an Integral Part of House Building in Northern Ireland

Mark believes that with the greater range of airtightness products available on the market over the last decade, the construction industry in Northern Ireland has adapted to such an extent that nowadays everyone involved at each phase takes it on board to ensure that houses are being built airtight and built better.

Find Out More

Follow Beam on Twitter

Transcript

Download a transcript of the interview with Mark Chesney.

The Future of Housing – Premiere

This week we completed the filming of our crowdfunded documentary The Future of Housing – And How Airtightness Can Help. Next stop: the edit!

So if you want to attend the London premiere, don’t delay because there are only 50 tickets left!

The launch takes place on Thursday 4th December 2014 at the Mildmay Community Centre and there are already some big names from the green building world booked in!

Be part of our special evening – get your ticket now.

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November 22, 2014
HPH043 : Building an Energy-Efficient Home on a Tight Budget – with David and Penny Learmonth
David and Penny Learmonth share their experience of building an ultra low energy home on a budget. They also project managed this themselves.

Interview with David and Penny Learmonth

David and Penny Learmonth have tackled three renovations over the years and this gave them the confidence that they could manage a new build project, creating an energy-efficient home for their retirement.

Initially they were inspired by John Christophers’ Zero Carbon House in Birmingham.

John Christopher’s Zero Carbon House. Photo copyright Martine Hamilton Knight

They Seized an Opportunity to Build

David and Penny lived in a listed property in Essex, UK, but around 2007 the planning envelope for their village was extended.

This meant that a paddock that they owned now fell within this new boundary and they were starting to get calls from property developers.

Instead of selling, they decided to take on a project themselves, which would also be an opportunity for them to build a more comfortable house with lower running costs.

A Simple Form is Easy to Make Energy Efficient

As the new house was going to be built next to the listed farmhouse, there were restrictions on what they could build.

After their initial design was turned down, their architect came up with a house that looked a bit like a calf barn. It would be clad in timber and have a slate roof.

The building was rectangular in shape, which was perfect in terms of energy efficiency.

David explains: “It’s very fashionable these days, as perhaps you’ve noticed, lots of gable ends and dormer windows, complicated shapes that of course makes it very difficult to build an efficient house because you have got all the risks of thermal bridgings and insulations and nasty corners to get round.”

The insulation layer goes down

A Tight Budget Meant They Had to Spend Their Money Wisely

This build was financially driven, because the company that David used to work for went bust, owing its pension fund quite a lot of money.

Using savings and inherited money they worked out that they could do this if they were careful. They would then sell their old house to fund their retirement.

So they spent their money on the things that really mattered: the fabric of the building.

For example, the light fittings they chose were bottom of the range as were the doors and sanitation. The big advantage of doing this was that these items could be easily upgraded at a later date.

Their House will be Adaptable to Changing Circumstances

After caring for her parents, Penny reflects on how people need more space as they get older.

So their simple and open plan layout allows for wheelchair access or hoists (and so on).

Although they have bedrooms upstairs, the house is essentially a bungalow and so they could easily live on the ground floor.

Touchwood Homes erect the timber frame

A Local Sustainability Network was a Great Resource

While at a Christmas party a friend recommended using local resource The Uttlesford Sustainable Homes Network.

Although this hadn’t shown up in any of David’s searches online, this website proved to be a tremendous help. From it they found their main contractor (Touchwood Homes), heating contractor and architect.

Understanding the Sequence of the Build is Important

David gives an example of how the big thermal store had to be put in place before some of the walls.

If this sequence hadn’t been taken into account there may have been issues with decorating because once the thermal store was in, it would be difficult to get to a lot of the plasterboard.

Solar Thermal Panels and a Log Burner Provide Heat

In order to create a zero carbon house, David and Penny wanted to move away from fossil fuels such as gas or oil for their heating and hot water.

So they use heat from the sun for part of the year and heat from a log burner for the rest (as they have a plentiful supply of wood).

In the summer, there is no need for heating and the solar thermal panels provide all the hot water they require.

When they get into winter the log burner is the heating source. As the heat goes into the water, too, there is little chance of the house overheating (because it is so well insulated).

David has been recording information on the amount of wood they have been using. The graph above shows the number of fires they’ve been having each week and the amount of wood they are bringing into the house (measured in wheelbarrows full).

Although they have a lot of wood, eventually there’s likely to come a time when they have to buy in wood. If the job is becoming too much for them in their old age, they could always replace the burner with a pellet burner.

The solar thermal panels are fitted

Changing Filters Protects the MVHR

As it’s an airtight house mechanical ventilation is necessary.

This is a low technology piece of kit that only needs its filters to be changed every so often. David stresses why this is done: “You get an interesting collection of insects on the filter with the air coming in. You get a rather depressingly grey sludge on the filter of the air coming out of the house, which I was excitingly informed was mainly dead skin, a really unpleasant thought but obviously you’ve got to protect the matrix from getting dirty otherwise it’s not going to work.”

Once the Build is Underway, Don’t Change Your Mind!

In the early stages, carry out thorough research and keep on refining your design. This ensures that once the ground is broken everything should run smoothly.

Resist the temptation to change your mind halfway through as this can be when things go wrong and money vanishes.

Check All Items as They Arrive on Site

The only significant delay on the project was due to the stairs. Although they had arrived in good time they had not been unpacked. As the spindles were wrong the whole lot had to go back and this had a knock-on effect.

It took about a month to get the stairs back, by which stage certain workmen had finished on site and so David and Penny had to wait until they were able to return.

Overall this cost money because they weren’t out of their old house.

Find Out More
- Read their blog about the build (which goes into a lot more detail)
Transcript

Download a transcript of the interview with David and Penny Learmonth.

Our Question for the Comments Section

What has inspired you to take on a low energy project?

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March 5, 2014
HPH041 : 5 Fundamentals to Creating a Better House – with Ben Adam-Smith
Ben Adam-Smith looks at some of the essentials that you need to understand if you are going to create an energy-efficient house. There is more detail in Ben’s new e-book: Why Most People Don’t Build Energy-Efficient Homes.

House Planning Help – Year 1

When I set up this website it was always with the intention of learning from other people, namely professionals who have accumulated a wealth of experience through their careers in construction, and self-builders (or custom builders) who have been there and done it as the clients.

Reviewing this body of material I was keen to discover if there were common messages for those in the research stages. I poured all of this into a mindmap to begin with.

Then I wanted to start again and put it all back together in a much more logical sequence. My aim was to produce a multimedia e-book that could reaffirm the key learnings.

So here are five concepts that I believe can take you a very long way when it comes to building an energy-efficient house.

1. Mindset – Keep an Open Mind

I bet no other building website will suggest this as one of the fundamentals of building an energy-efficient house, but I really want to put this down as step one!

My reasoning is because we come into this with baggage. We have lived in houses all our lives, so when it comes to building one we probably think we know what we want.

If you are genuinely wanting to build an energy-efficient home that also has a low impact on the environment, this must be your priority. So keep an open mind while you’re doing your research rather than being prescriptive and then trying to bolt-on the ‘eco’ side of things.

I believe this will pay dividends because you can deepen your understanding of how houses have advanced and what you could have from a 21st century house.

A smaller house caught between two mansions!

2. Scale – Not Too Big!

The size of your house matters.

You will make hundreds, if not thousands, of decisions about your house but this is one of the most significant.

Increasing the floor area means that other costs increase too. Larger houses have larger build costs, larger running costs and larger maintenance costs.

In the life cycle of the building this can really add up.

So spend time really considering how you can get more from less. For example, when it comes to rooms a study is rarely used at the same time as a guest bedroom so is there a way to do double duty?

Scale is ultimately down to personal preference but keeping our ambition under control can have a massive impact. While the Tiny House movement might be at one end of the spectrum it’s fascinating to see how these people do not feel like they’re missing out – if anything they are a more positive group!

3. Optimise – As Much as You Can!

It’s a crying shame that houses are often built with no intention to make them as good as they could be.

We are in an era where we should be striving to optimise as much as possible about our houses. The ultimate aim is to get the most from the least amount of resources while minimising waste.

So when it comes to housing this should include:

a) Carefully considering the location of the plot – have we chosen somewhere that will reduce our dependency on cars?

b) Orientating the house to benefit from sunlight – why wouldn’t we take advantage of this free source of light and heat?

c) Creating a dwelling that is aesthetically pleasing – this has to be the full package.

e) Personalising the house – this has to have our own stamp on it or else what are we doing!

Tools can help us when it comes optimising our houses. The Passive House Planning Package, for example, allows us to test buildings before they’re even built and try different variations.

This way we can make intelligent choices about our design knowing what the consequences are for our future comfort and energy bills rather than finding out the hard way when the building is finished.

4. Fabric First

These days most people don’t need much convincing that a fabric first approach is preferable to bolting on technology to try and neutralise your carbon footprint.

The reason is that bolt-on technology is not part of the building. By investing in the fabric of the building – the walls, doors, windows, floors etc. – we can create a high quality building envelope that will largely last for the lifetime of the building. And therefore this can do all the hard work.

Airtightness and high levels of insulation are the two most important factors when it comes to keeping the heat in (or the heat out if you’re in a hot climate).

I would encourage every person who wishes to create a low energy house to learn about the Passivhaus standard. This goes beyond fabric first and sets various criteria that a house must meet in order to be certified to the standard. Not only does this save energy but there are huge benefits to occupant comfort as well.

5. Simplicity – Embrace Eco-minimalism

Building an ultra low energy house does not have to cost more than a standard house but – and it’s a big ‘but’ – you have to spend your money wisely and make energy efficiency the priority.

For example, if you desired to reach the Passivhaus standard you would know what that means. There would be certain non-negotiable elements such as your house would need very high levels of insulation, triple-glazed windows, mechanical ventilation with heat recovery and so forth.

Accounting for these items and almost working backwards, you are then left with a certain amount of money to design and specify your house. This is likely to mean avoiding complexity, because that inevitably results in higher costs, and instead keeping the form and detailing of the building simple. That doesn’t mean boring, but it does mean finding the elegance in simplicity.

Few construction professionals think like this but it is entirely possible.

A Big Thank You

In case you are wondering whether this e-book might be flawed because it’s written by a novice, well I’ve tried to prevent that from happening. Elrond Burrell, an architect well known on social media and a prominent advocate of the Passivhaus standard, has worked with me on this project (he is also an associate at Architype but has helped me in a personal capacity) allowing me to have a voice but pulling me back when I start making it up! So I must say a massive thank you to him.

Elrond is launching his own blog later this year and you can be sure we’ll be supporting him in any way we can.

What More Do I Get From This E-Book?

I have tried to make this something that is both fun and informative, which is one of the reasons why I decided to publish this on the Snippet App. Snippet is a new platform that goes beyond what a conventional e-book can do and turns it into a multi-media experience. I feel this format has a lot of potential when it comes to enhancing the learning experience.

Anyway in this e-book I go into more detail about the concepts outlined above. I also look at natural materials, retrofitting and have some tips for project success.

There are photos of completed Passivhaus standard projects and videos that I’ve put together to illustrate some of the themes. You even get a chance to see my childhood home!

Why Should I Buy This E-Book?

I’ve put this Snippet together for those who want to create their own energy-efficient homes. Hopefully we have similar objectives and you have found these blogs/videos/podcasts useful. So I hope this e-book will do the following for you:
- Accelerate you on your journey
- Provide a much more logical sequence and better way to learn
- Reaffirm some of the things you already know
- Highlight the decisions that have monetary and environmental consequences attached to them
I personally think this e-book is exceptional value (although perhaps I would say that as the author who wants to shift some copies!). The Snippet App sets the price of these downloads so for $5 I feel you cannot go wrong.

The final reason – perhaps for those who work in the industry! – is to help me. I have given away lots of free information on House Planning Help but putting together products like this take time. I won’t lie – I love being able to create content like this but to support me in what I’m doing here it would be fantastic if you could buy a copy. Thank you in advance.

Buy E-book Now

Go directly to my author page on the Snippet App.

OR
1. Search for the Snippet App in the App Store (on your iPhone or iPad).
2. Install the Snippet App.
3. Buy ‘Why Most People Don’t Build Energy-Efficient Homes’. Then start reading. Enjoy!
There’s is also a Kindle version available, too, although the book is best viewed on Snippet.

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February 5, 2014
HPH005 : The Passivhaus Standard #3 Retrofitting to Passivhaus (Passive House) – with Adam Dadeby from Passivhaus Homes
Adam Dadeby from Passivhaus Homes talks about some of the challenges he faced when retrofitting his own home to the Passivhaus standard. He’s also co-author of a new book called The Passivhaus Handbook.

Interview with Adam Dadeby

Adam explains that it was while he was studying sustainablilty at the Centre for Alternative Technology in Wales that the Passivhaus standard caught his attention. He particularly liked the fact that it focusses on a narrow goal of energy usage, which is backed up by science and the practice of what works. It also thinks about how people use buildings and how occupants behave in buildings. Detail and quality are fundamental.

Sustainability Approaches

Adam gives examples of some of the other approaches he looked at in his studies, which include those that focus on Carbon more than energy (in terms of its resource usage during the lifetime of the building), those which are about natural materials and low embodied energy (low impact materials), and others which are absorbed by gadgetry and technology.

The Code For Sustainable Homes

In the UK, the Code For Sustainable Homes has up until now concentrated on Carbon. This has not had the desired effect, creating inefficient buildings plastered with PV and a woodchip board that no-one knows how to use or service. The Passivhaus approach is to address the fabric, to get the building to demand as little energy as possible. The choice of how you then provide that little heat that is required is a secondary consideration.

Energy Performance Standards

Adam explains the benefits of aiming for a fabric focussed energy performance standard.
If you’re retrofitting there is also the EnerPHit standard.

Insulation Constraints on His Retrofit Project

Using natural, low embodied energy and low impact materials is something that Adam would always want to do. However, when retrofitting his home there were severe space constraints imposed by the existing structure, making it difficult to use sustainable, but less thermally efficient, insulation. The impact of changing certain aspects of the design and materials can be modelled with the Passive House Planning Package, which helps you what the effect is on the energy performance.

Four Ways to Measure Floor Area in the UK!

Adam reveals to Ben that there is no agreed method of how to measure floor area in the UK, making comparisons of certain aspects very difficult. Ben cannot quite believe this! Germany keeps it simple with one method to measure floor area… again leading the way.

Refurbish and Extend, or Build New?

Adam emphasises the importance of spending time to get the brief right. He always wanted to get his house certified to the Passivhaus standard and so his biggest decision was whether to refurbish or build from new. His decision to retrofit was driven by the belief that he needed to save and re-use materials because his house had a lot of concrete in it. With the added complications and increased costs, in hindsight he says that he would probably have built new.

Policy Changes

In the UK there are tax benefits which favour new build. Adam suggests that a better approach could be to link the VAT rate to the energy performance of the final building. This tweak, which could be revenue neutral overall, would provide a huge incentive to build low energy housing. He also believes builders will do the right thing if they understand why adopting new methods is so beneficial. That’s where training schemes could educate on the importance of airtightness.

Cultural Change is Needed Too

Reducing our throwaway culture and investing in the quality of buildings is a mindset we must adopt. We have become blinded by items that have a low initial capital cost, but require ongoing monthly payments (satellite TV and mobile phone subscriptions etc.). As you are likely to live in your new house for years and years, spending a bit more to get something that lasts is a lot greener.

The Passivhaus Handbook

Co-written with RIBA architect Janet Cotterell, Adam talks about his new book the Passivhaus Handbook, which is aimed at all those considering building with this methodology. The book offers practical advice as well as enough detail for architects, builders, planners and the like to become better informed. It also has a section that is specific to the UK and another section about what it’s like to live in a Passivhaus.

This is our affiliate link to buy the Passivhaus Handbook on Amazon.

Adam’s Top Three Tips
1. Try not to change your brief. This is a good idea on any project but more so with Passivhaus because the implications will ripple through the build.
2. Be modest with the size of house you want. Consider what you really need. The bigger the house, the more energy it’s going to use (irrespective of anything else).
3. The trio of client, architect and builder need to trust and cooperate with one another. This is the most important success factor for any build.
Transcript

Download a transcript of the interview with Adam Dadeby.

Building a House You Both Want!

Ben Adam-Smith describes his first major mistake – getting carried away on a solo mission and not involving his wife in the process of thinking of their new home! Basic error, yes. Argument, yes. The lesson that has been learned: if you are in a relationship, you have to be deciding things together. You have been warned!

Updates for Homebuilding and Renovating Magazine

There’s exciting news. We will be posting updates on Homebuilding and Renovating’s website about what we get up to on the House Planning Help Podcast.

Totnes Passivhaus Bed and Breakfast

If you’ve ever wondered what it feels like to live in a Passivhaus, then Adam Dadeby may have the answer. After retrofitting a property to the Passivhaus standard, you can now stay at the Totnes Passivhaus Bed and Breakfast and experience the excellent comfort and superior air quality for yourself. It’s the only Passivhaus holiday accommodation in the UK (as far as we are aware).

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September 25, 2012
Is It Worth Spending The Extra Money To Build Your House To a Low Energy Standard?
In recent years there has been a cultural shift away from buying items of high quality and a move towards cheaper goods. This seems to apply in many walks of life, but it could be argued that it creates a false economy. While it caters for immediate needs, the items in question rarely last long and must soon be replaced. Due to the cheap design and materials from which the product is made, there may also be next to no recycling value.

There’s a similar situation with satellite TV subscriptions and mobile phone rental (or even buying a printer or electric toothbrush), the upfront cost is temptingly low and somehow the ongoing monthly costs don’t feature that much in the decision-making process. It’s a form of credit, where we probably know there is a better way of doing things but we’re living for today!

Oddly it doesn’t apply across the board. Look at the case of Apple computers, which are substantially more expensive than PCs but have a certain kudos. Perhaps a new car might be a status symbol… So what might our thinking be when we come to build a new home?

In terms of meeting a low energy building standard (let’s consider Passivhaus), it is true to say that – at this point in time – it costs more, but only fractionally more. The upsides, however, are considerable.
- You get large savings on your bills (due to minimal heating requirements)
- You have less maintenance to do (because there’s less heating infrastructure than a traditional house)
- The air quality is good (with a ventilation system) and there are no draughts
- It’s quiet (because the house is sealed and there’s triple glazing)
- The overall build is robust and long-lasting
With the average self builder moving every 25 years, spending a little bit more on your construction for all these added benefits seems like a common sense judgement. It should be a greener choice too!

*Episode 3 of the House Planning Help Podcast starts a mini series on the Passivhaus standard*
August 25, 2012