bdonline Blog

I am adding this intro 8 years after the first post was written. Having read them all again I don’t think there is anything I don’t stand by today.

I was asked to write the Sustainability Blog for bdonline. It was unpaid but I enjoyed  the chance to refine my thinking about some things  I had been musing on or discussing with friends and colleagues.

I find writing difficult and these posts owe a lot to the help and feedback of friends as well as editorial input from Kate de Selincourt. All errors And typos are mine. Regular discussions with Alan Clarke, as we try and make sense of the work we do, had a big influence on these posts.

I cannot claim credit for any of the ideas expressed but to name others who helped me shape these thoughts would risk me missing key influencers.

After writing the few posts that are all pasted here my enthusiasm waned. I felt I was repeating myself and preaching to the converted whilst being misunderstood by those I was hoping to reach.

Nick Grant April 2020.

You can read and comment on Nick Grant’s Sustainable Building blog at bdonline. You need to register but it is free.

See also the BLOG on this website for short topical posts and of course follow me on Twitter!

Previous posts from The Sustainability Blog:

Allowable Solutions, a brilliant idea

Posted by: Nick Grant, 16 August 2013

Allowable Solutions are up for consultation and this seems like the makings of an excellent idea that needs bold leadership to take it to its logical conclusion. The language used, with phrases such as “big society”, “localism agenda” and “capital magnets”, reassures me that this will be something really special.

I cannot claim to have read all of the hundreds of pages of documentation, but I did spot some Marginal Abatement Cost (MAC) curves in one of the PDFs and that got me excited.

In this context, a MAC curve is a chart listing all the climate change abatement measures we can think of, with the X axis representing the amount of CO₂e abated by the measures and the Y axis the cost per Tonne of CO₂e avoided. The idea is you start with all the measures that save money (negative cost) and work your way up through cost neutral measures to more expensive solutions until you have saved enough theoretical CO₂. Whilst the assumptions are always problematic, the concept is good.

Marginal abatement cost curveMac curve reprinted in Allowable Solutions: Evaluating Opportunities and PrioritiesSeptember 2012, Zero Carbon Hub. (Original pasted from Green Deal and ECO impact Assessment 2011)

This means that rather than investing in relatively expensive solar panels on fiddly little roofs in less than ideal locations, the housebuilder can put money into the most cost effective measures maximising bang for the buck, a win-win situation. This feels so much better than being told to stick your PV where the sun doesn’t shine.

Once buildings are properly built following the mantra of fabric first, transport becomes the elephant in the room in terms of building-related carbon emissions. However it would take very little effort to add a green transport Allowable Solutions charge to the formula. This could be banded by location with no charge for dense urban developments.

What is brilliant about the Allowable Solutions concept is that it can be applied to a whole range of measures that make so much more sense tackled on a bigger scale. Rather than paying £1000 for an ecology report for a single dwelling in Balham, how about buying 10 acres of rainforest in Bolivia? Also an allowable flood solutions fee could be paid, rather than requiring very expensive and ineffectual individual rainwater systems to meet the SUR 1 criteria of the Code for Sustainable homes.

Depending on your political persuasion this money could be paid to an NGO, to local councils or to private companies distributing corporate branded sandbags or renting  flood plains for flood alleviation.

The less public-spirited might see this as some sort of stealth tax. They might ask why the struggling construction industry is singled out to foot the bill for climate change mitigation? Others might ask why the most cost effective measures such as LED street lights are not being done anyway, as good local government investments — rather than funded by builders of new homes.

Those who see climate change as an actual problem that needs tackling with some urgency might suggest that it is a bit daft to set up such a complex scheme only to be funded by a levy on a few new buildings, when and if we start building again. Being such a great idea, surely we should all chip in? Perhaps this is what big society means, we all work together to solve the biggest threat to civilisation?

Of course detractors will argue that this is all too little too late and we should be thinking of adaption not mitigation. For them I propose “Unthinkable Solutions”. This would allow developers to fund measures such as sandbags for Bangladesh, or security fencing for autonomous rural eco homes in the UK.

By Nick Grant

Supply and demand

Posted by: Nick Grant, Fri, 19 Oct 2012

After HD Thoreau’s death in 1862 his friend Ralph Emerson wrote: “He chose to be rich by making his wants few”. In trying to live off the land, Thoreau realised that radical simplicity was essential. He did the numbers and saw that keeping an ox would greatly increase — not reduce — his workload, as it would require care and feeding. This would require more land to be rented and tilled. Fattening a pig made no sense either if he generated little waste.

scrap sculpture

Source: freeimageslive / cornishpasty/ Creative Commons

In Energy and Equity, Ivan Illich carried out a similar analysis for cars. Estimating the time spent travelling, sitting in traffic and working to pay for the capital and running costs, he calculated that the average American spent 1,600 hours to get 7,500 miles: less than five miles per hour. He didn’t include accidents, road infrastructure or time spent watching Top Gear repeats on Dave.

I’d be the first to pour cold water over romantic ideas of the good life, but I think Thoreau and Illich saw how, in todays jargon, focusing on the “supply side” of the environmental problem can fail to deliver actual resource reduction.

My hunch is that the world is divided into “less is more” demand side people, who focus on reducing their demand for emissions-heavy products and processes, and “less is a bore” supply side people, who look for solutions within the sector that emits them – it is a personality trait. Inspired by a typo, Amory Lovins coined the term negawatts (and negalitres) to quantify energy or water that is saved rather than generated. This is a difficult idea. Not using resources is a surprisingly abstract concept that needs a catchy name. It is easy to measure what we generate or consume, but savings can’t be directly metered and can only be estimated based on assumptions about what the base case might have been.

People with on-site renewables are rewarded by readings of the export meter. My friend who invested in photovoltaics to make his electric Aga “carbon neutral” can whip out a statement from the electricity company showing how much he has been paid this quarter. Perversely, the more of his solar electricity he burns up, the more he saves. There is no such excitement for those choosing not to fly, topping up their loft insulation or even building a near zero-energy house.

This is not sour grapes, it is just a fact that consumption has so much more appeal than non-consumption. Humans aren’t programmed to seek less, so proponents of radical demand reduction have an uphill struggle to sell the idea to those that don’t naturally get it.

Instead of generation targets, demand-side environmentalists talk dryly about our carbon ration or ecological footprint and are forced to highlight the fact that we need to consume less. Meanwhile supply-side advocates can promise future fixes to meet any demand. These might be new oil discoveries under Arctic ice, nuclear power too cheap to meter or deserts full of solar collectors turning air and water into aviation fuel. On the demand side we can design buildings to need almost no heat or cooling and develop low-impact biomaterials. But if we want to travel great distances at high speed then a bicycle doesn’t cut the mustard for me, even if Illich shows it takes less time. Doing more with less is a great mantra but to suggest doing less with much less is political and commercial suicide.

But does a supply-side approach avoid the need to address consumption? It seems clear to me that a renewables powered future is impossible without embracing both radical efficiency and “making our wants few”. Renewable energy just doesn’t have the same oomph as fossil fuels.

What about more bold, futuristic solutions such as nuclear fusion? Might we be saved at the last moment by the technological cavalry? James Lovelock once suggested imagining a device the size of a suitcase, that runs on seawater and delivers electricity through a couple of 13A sockets. No pollution, no CO2, the perfect (supply-side) green technology. Deserts bloom irrigated with desalinated seawater and we can feed billions more people. We can even turn raw sand and rock into beautiful glass and steel buildings with wonderful forms constrained only by human imagination, unfettered by the tedious critique of sustainability consultants. I know I’m a pessimistic old git, but I really don’t see such a utopia lasting long.

I’d be interested to hear if there is a novel that plays out this modern day equivalent of the Midas myth.

The demand side utopian equivalent might be buildings that stay warm with sun and body heat or computers with electronic ink displays (think next generation Kindle) that run on light. These technologies are possible now and don’t hint at a dystopian outcome. While lacking the excitement of a free energy generator, a laptop that is silent, stays charged, weighs little and can be used in direct sun won’t need a green subsidy to promote uptake.

While I’m confident that, for example, the ambient energy computer is feasible, it will soon be on the way to landfill unless we apply the demand side approach to software as well. Otherwise computers will continue get ever more powerful, allowing us to do more and more things that we didn’t know we needed to do. “Everything is amazing and nobody’s happy”, a clip on YouTube by the comedian Louis CK, is a not to be missed diversion that sums this up nicely.

The runaway computer upgrade cycle is a serious sustainability problem in itself and it is common for the poor energy performance of new buildings to be blamed on the burgeoning IT load. If you think I have wandered too far from the blog’s building focus then consider the serious proposal to heat homes with “data furnaces”. This seems neat but like the fashionable idea of turning uneaten food into biogas, Thoreau would have had something witty to say about it.

I suggest that if we continue to prioritise a supply-side approach we will be locked into a spiral of increased consumption. Even without Lovelock’s imaginary machine to speed our decent, a green trajectory will not save us from climate change or resource depletion unless it makes demand reduction the focus. We can cover all surfaces with PV, cut down all the forests for biomass, plant palm oil to fuel our vehicles and install greywater recycling and heat pumps in all buildings, but – as with the latest computer – demand will always be just ahead of supply. Success should not be judged by the amount of green kit installed but by how close to sustainable levels of consumption we get.

If, as Thoreau concluded, prioritising radical efficiency is the only sustainable option, then we need to rethink our entire approach and match demand to supply rather than fleeing into the future in a futile attempt to match supply to demand.

Comments (5)

Kicking up a Stink

Posted by: Nick Grant, Mon, 13 Aug 2012

Compost toilets don’t feature in bathroom catalogues and yet they are one of the iconic green building technologies.

So it is worrying that a recent Guardian Environment Network article reported on the failure of the “world’s biggest eco-toilet scheme”. Residents of the Daxing eco-community in Inner Mongolia suffered serious odour and health problems before winning a battle to have conventional flush toilets installed.

The residents are now happier but the article suggests that the community has “lost its most important symbol” the dry toilet. The flush toilet and piped sanitation is arguably the most important symbol of modern civilisation. If waterless toilets are the most important symbol of a sustainable alternative then in the light of this story we need to revisit the technology and/or our thinking about what is sustainable.

When we built our home my partner insisted on a dry toilet not for green reasons but for functional and aesthetic reasons. After many years of research and tinkering we knew how to make a compost toilet that had absolutely no smell, was silent in use, needed no water and was easy to clean.

Ceramic compost toilet pedestal

The author’s own compost loo – no air freshener needed and only a 2W vent fan

By comparison a flush toilet is smelly, splashy and noisy and, in our rural location, usually requires an annual visit from a sludge tanker to empty the septic tank. We love our compost loo and yet I regularly talk enthusiasts out of them. This is because of a number of mundane considerations such as the need to design the building around the toilet and the fact that a compost loo is living thing that will fail if abused or neglected. For all its shortcomings, the flush toilet does a good job in a wide range of situations and with good design it need not use much water either.

Conversely, I have heard advocates of less effective dry loos argue that it is morally wrong to flush and forget, that it is right to be reminded that our shit smells. I’m not of that school of thought. I strongly believe that “sustainable” technologies have to work better than conventional ones, for me that’s part of the definition. An eco-car will never go as fast as a Maserati but few choose to drive a Maserati and it’s not just a question of insufficient wealth.

NatSol Compost toiletA Natsol dry toilet with building designed by Chris Morgan Image courtesy of Locate Architects

Don’t confuse my scepticism with cynicism as I rubbish yet another green icon, it is only the unquestioned iconic status that I wish to rubbish. In 2005, I set up a small company with long time collaborator Andy Warren []. We wanted to develop a state of the art compost loo for applications such as allotments and remote sites where we thought they really made sense. We now have over 300 installations and the business is going from strength to strength. This is because the product aims to be a “better mousetrap” not because we have identified a naïve consumer group eager to buy into a green lifestyle.

Uncommon sense

It does feel wrong to shit in pure drinking water but as often happens in this field, when we take a dispassionate view, the self-evidently wrong approach can turn out to be the most environmentally and socially responsible. Mains water has a lower life cycle impact than rain or grey water in the UK and gravity sewers are a zero energy miracle of Victorian engineering that have required surprisingly little technological improvement.

However, I had always assumed that dry toilets would be the technology of choice for low cost sanitation in slums where the water supply is at best erratic. It doesn’t take much imagination to appreciate the benefit of a simple hole in the ground over a heavily used Western style toilet without a functioning water supply. But an inspiring RSA lecture by Himanshu Parikh in 2004 turned my assumptions on their head in the way the best talks and writing do (Ted version of the talk). Parikh’s story of the far reaching and cost effective transformation achieved by bringing low cost piped sanitation to slums in India is an excellent example of the application of science, uncommon sense, good engineering and the questioning of assumptions. Do watch the talk, the contrast with the Daxing story is profound.

Sustainable building without the greenwash

Posted by: Nick Grant, Wed, 11 Jul 201

If you are really interested in sustainable building and have not joined the AECB (don’t worry what it stands for) or been to one of the annual conferences then you are really missing a trick. The recent conferencewas held at Goldsmiths in the New Academic Building designed by AECB members Stride Treglown. A week later I am still buzzing from the experience.

The very friendly and informal atmosphere might suggest a gathering of like minds and a cosy reaffirmation of shared beliefs but nothing could be further from the truth. Within this group you will find people who refuse to use cement or petrochemical-based insulation sat in a workshop on life cycle assessment tools with those that routinely do.

Sally Godber’s presentation on ventilation

There is plenty of philosophy discussed at the AECB Conference — i.e. “thinking about hard problems” (as Lewis Wolpert summed up the discipline at Hay Festival this year) — but serious progress happens through that old offshoot of philosophy, science. Real science takes a lot of time to do properly, one small variable at a time, testing hypotheses with evidence. However in our work we are dealing with complex buildings variously separating and connecting complex people from an often hostile and complex outdoors. To make things more difficult we need answers now for current projects and there is no research budget and even less time. As the ever quotable Peter Harper would say, “too many varying f*ckables”.

So while we wait for solid scientific evidence to dribble in, we build on what we know and try to develop our bullshit detection skills. We grasp at what seems to work while being painfully aware that most things we have ever believed in turned out to be wrong.

Thus there is a hunger to hear about what goes wrong, not for theSchadenfreude but to learn from the expensive mistakes of others. The unspoken price for this fount of invaluable knowledge is that we also share our lessons. I don’t know much about the open-source computing community but I suspect there are parallels — most AECB members are remarkably generous and open when discussing details with, let’s face it, their competitors. These are not naive amateurs but some of the leading practitioners in the field.

So with my head already full at the end of two days, Wolfgang Feist arrived from the Passivhaus Institut to lead a joint AECB/Passivhaus Trust masterclass as the first leg of a UK tour stopping in Glasgow and Cardiff before returning to London for the first UK Passivhaus Awards.

The Passivhaus Trust was set up by the AECB and there is a lot of overlap in the membership of both organisations. I don’t think this is surprising given the similarities in approach with a commitment to openness and sharing for mutual benefit. That said, not all AECB members are advocates of Passivhaus as evidenced by Professor Sue Roaf’s presentation on adaptive thermal comfort at this year’s conference or Professor Brian Ford’s presentation on natural rather than mechanical ventilation at last year’s conference.

I know I alienate some readers by even mentioning Passivhaus and I will endeavour to write a Passivhaus free blog post soon. But for those I risk alienating, I would be delighted to hear about alternatives that offer such proven building energy performance. Your comments are welcome and we can all benefit from open debate.

Zero Intelligence

Mon, 21 May 2012

I would like to suggest that zero carbon buildings are a flawed concept – at least that is the conclusion of a paper I presented at the International Passivhaus conference a couple of weeks ago.

The high cost and impracticality of zero carbon buildings as originally conceived has now been acknowledged but, rather than dropping the idea, ‘zero carbon’ is being redefined. This is costing huge amounts of time and money and is leading to complex fudges such as ‘allowable solutions’.

To our credit the UK is ahead of the curve. In the US and on the continent they have yet to agree on a zero energy building definition and so may be some years off redefining it.

I’m happy with the building as the boundary to set challenging energy efficiency standards, and we should not be allowed to compensate for poor efficiency though offsite offsets. The nice thing about energy efficiency is that measures tend to be very cost effective, even cost negative. Once you have learnt to design in airtightness or design out thermal bridges, it’s easy. Optimising building form to reduce heat loss area also reduces build cost. We can also expect the building to be more comfortable and to stay warm for days if the power goes off.

However to get to zero, efficiency isn’t enough. We need carbon free energy and the options are limited. For domestic buildings this probably means PV for electricity and burning wood for heat.

I have wider concerns about biomass but the issue here is the accounting paradox that making a zero carbon building more efficient doesn’t seem to reduce emissions; 80% of zero is still zero. In practice this is not true. All bio based fuels are a limited resource. If I heat my zero carbon castle with wood and run my zero carbon Land Rover on biodiesel then I am in effect forcing someone else to use fossil fuels. This is why, sadly, we can’t really have zero carbon jet travel, the alchemy of turning veg oil into aviation fuel isn’t the issue.

The paradox is solved if we attribute the actual emissions from the flue or exhaust to the building or vehicle. Then it becomes clear that the zero carbon Land Rover has twice the emissions of the zero carbon VW Polo as twice as much CO2 comes out of the exhaust for every mile driven. In solving the divide by zero problem we expose the illusion of the zero carbon vehicle or building.

The Strata Tower, Elephant and Castle (AKA the ‘ladyshave’) : buildings are not power station.

But, we argue, the biodiesel we put in our Land Rover is made from waste that would have gone to landfill, how does that get into the equation without making both sides zero and so meaningless again? Simple, we consider the emissions due to diesel to be equal to the pool value from all fossil, biological or synthetic sources, i.e. mostly fossil. We can apply the same logic to biogas and solid biomass as well as electricity. This approach credits sequestration, renewable generation and efficiency and penalises waste.

We can repeat this thought experiment to electric cars charged by our own PV array.

At the recent International Passivhaus conference in Hannover there were many presentations from speakers excited about the fact that Passivhaus makes it easier to achieve a net zero building. Having reduced the heat demand it might be possible to fit enough PV on the roof to meet the theoretical energy demand of  a building without resorting to burning biomass. I find this muddling of the objectives disappointing. The  spurious ‘cancelling out’ of the residual demand disguises the true achievement of a Passivhaus, which is getting that demand as low as is sensible.

The zero carbon target does nothing about the vast majority of existing buildings and all the other emissions that we need to tackle. By focusing on a daft target for a few new buildings we divert attention and limited resources from the mind-numbingly huge challenge that faces us. And I suspect that is what the psychological and political appeal of zero carbon buildings really is.

“It is a great art to remember that boundaries are of our own making, and that they can and should be reconsidered for each new discussion, problem, or purpose. It’s a challenge to stay creative enough to drop the boundaries that worked for the last problem and to find the most appropriate set of boundaries for the next question. It’s also a necessity, if problems are to be solved well.”

Dana Meadows, in Thinking in Systems

Why bother?

Posted by: Nick Grant, Tue, 24 Apr 2012

Only two blog posts in and I want to air my unease with the title “The Sustainability Blog”. I could pretend to have a problem with “the” but it is “sustainability” I struggle with.

I have been interested in sustainable design since I was a kid in the late 1970s when it was called, among other things, Alternative Technology. Like the comedy genre, Alternative was cool and edgy; now AT is no longer alternative.

And yet despite this success there is little reason to celebrate. While the technology has been shown to work, the scientific consensus is that we are screwed. It’s not that we don’t know how to make the transition to a sustainable future, it’s that collectively, we don’t really feel the urgency, I mean REALLY feel it.

George Monbiot touched a nerve at the AECB conference a couple of years ago when he pointed out that for all our exemplar low energy buildings we really are pissing in the wind. And that’s my embarrassment with writing about sustainability: it’s as ridiculous as writing about world peace.

Both are as technically feasible as they are humanly unlikely.

So do we give up? I’m an optimistic pessimist. As individuals we are all going to die anyway and as a species we will soon have been an insignificant blip compared with the dinosaurs. But that doesn’t stop most of us getting up in the morning. It’s my nature to try and fix things so I’ll do my bit to help make buildings work better with significantly less resources.

This is part of the human condition: to be able to know where we are heading and yet to carry on as if what we do matters. I’m heartened to see others excited by the challenge of doing the same. Tackling any big problem needs an obsessive attention to detail but we also need the harshest critics to shake us when we lose the bigger picture or are wasting our short lives heading down blind alleys.

As Peter Harper, who coined the term Alternative Technology 40 years ago pointed out, its not really about sustainability. It’s more about choosing whether we want the future to be more like Denmark or Mad Max.

A matter of priorities

Posted by: Nick Grant, Mon, 26 Mar 2012

I only promised a blog a month but I need to get something off my chest.

I just read a good article in Building Magazine about a proposed “sustainable school” that was axed in favour of a lower than standard specification school, supposedly to save cost.

Although the article suggested that there was little or no over cost for the sustainable option, the argument made was that it’s the kids’education that matters, not the building. This is a very emotive put-down, It’s not comfortable to be arguing for better u-values when the client is saying “But what about the children?”

Laurie Baker architect

Laurie Baker

This resonated with so many similar statements that I have heard in meetings over the years: “Obviously we are committed to sustainability but it mustn’t compromise the budget/design/function/delivery etc etc.”

Now I don’t want to get into the argument about whether this particular proposal was any good, or whether architecture influences learning. I don’t know the project and am not qualified to opine on the latter. What got my goat was the idea that sustainable design is some sort of optional add-on, that there is a choice to be made between the kids having a teacher and them having a building that doesn’t waste resources.

This is not a zero-sum game; we don’t have to choose between sustainable design and books for the kids, any more than we have to choose between a mouse-proof larder and food to go in it.

I’m happy that any measure is questioned with the utmost scepticism and rationality. Consequently I no longer have patience for zero-carbon buildings, biomass heating or the Code for Sustainable Homes, but I react strongly to the flawed logic that sustainability is not affordable.

This only makes logical sense if we don’t believe in climate change or finite resources. In that case then sure it’s silly to waste money on this eco nonsense but we need to be straight and say we think sustainability is silly – not that we can’t afford it.

The logically perverse additional qualifier that made me really cross was the idea that we can’t afford sustainability in a recession. Think about it. Can we only afford to build sustainably in the most prosperous countries during times of unsustainable economic growth? As a friend just pointed out, sustainability is, essentially, affordability.

Rant over. If you have not seen the late Laurie Baker’s architectural principles, then I would recommend downloading this single side of A4 text to stick on the office wall. . Baker had affordability and sustainability in his veins. I only met him in passing, but three months spent living and working in some of his buildings in Kerala made a lasting impact on me. There is nothing like a really tight budget to inspire creative solutions, like using bricks on edge so they go further.

So, if sustainability is seen as the victim of value engineering rather than the outcome of it, then either the approach is wrong or cost is being used as an excuse to axe something that the team has no real heart for in the first place.

New is not always best

Posted by: Nick Grant, Tue, 28 Feb 2012

Passivhaus School

The first three Passivhaus schools in the UK were certified last week. It was agreed that they would all be announced together to avoid an undignified scramble for the finish line. So we all won but the one in Devon is the first zero-carbon Passivhaus school and the two in Wolverhampton are the first built for no extra cost.

The clients and designers deserve a huge amount of credit for daring to be first; but the obsession with firsts is irksome because it promotes the idea that innovation is inherently good. These days innovation might be a prerequisite to secure funding, win an architectural competition, get planning permission or earn that innovation credit, but, as in nature, the vast majority of innovations simply don’t work, while the best ones are usually too subtle to be labelled as an innovation by a BREEAM assessor.

Random innovations and natural selection deliver perfection over millions of years, but there’s a quicker way to deliver better buildings. It’s smarter to refine what has been proven to work, rather than feel compelled to reinvent the wheel every week because round wheels seem so last year.

Moving on

I was on the team for the Wolverhampton schools designed by Architype and built by Thomas Vale Construction. While there was a buzz about being first I am much more excited about our fourth school which is now at stage C. Here we have been lucky to keep the same team so we can build on what we have learnt.

First time round there was nervousness about specifying boilers and radiators as small as we had calculated because it was such a big step from normal practice. Now we know that we really can heat a 2,400m2school with a domestic-size boiler and one small radiator per classroom, so we can relax, reassured that the laws of physics do indeed apply to buildings, and go on to build on this confidence.

By going down the Passivhaus route we are able to tap into a huge body of experience and an international community passionate about building performance and largely willing to share and help its members out. An obsession with being first does not encourage such cooperation.

There is no budget for a Soft Landing programme but we are doing it anyway and it is providing invaluable feedback for the next projects. We sold Passivhaus to the client on a promise of closing the performance gap between design and reality so we can’t walk away and blame the occupants, even though the caretaker had cranked up the frost stat for the sprinkler pump to dry his coat, creating the same CO2emissions as heating the whole school would!

Check your own frost stats and try and design them out next time. But does an insulated pump room count as an innovation, or do we need wind-powered trace heating for that credit?

And yes, in hindsight we made a lot of innovations that we are really proud of. Jonathan Hines and Alan Clarke will share some of them at the international conference in Hannover and solicit feedback from those whose first Passivhaus buildings went up many years ago. However these innovations were driven by the needs of the site and the client and they are not obvious to the untrained eye.

What we put into a building might make it good but it’s what we leave out that has the potential to make it great.