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Passivhaus: Just for Energy Geeks and Treehuggers. Isn’t it?

This is a guest post by Architect, Elrond Burrell, where he shares why Passivhaus is so important to the construction industry and beyond.

Passivhaus is known as the worlds leading energy efficiency standard for buildings. It drives building energy consumption down as much as 90%. This means paying very close attention to how a building is designed, detailed and constructed to ensure energy is used efficiently and not wasted. It means undertaking very detailed energy and performance modeling during the design process. This can all seem a bit complicated and geeky, so why not leave it to the geeks who love this kind of thing? And only Treehuggers are so into saving energy aren’t they?

Actually, no. Here are three reasons why you should care about Passivhaus: Climate Change, EU legislation, and because you can make a difference.

1. Climate change

Looking at the big picture, climate change is the major issue that we have to contend with across the board. There’s no denying now that rising CO2 levels and climate change and everything else that comes with it are all happening. What we do today to respond to this is critical. And this includes the built environment and building design.

Buildings play a significant role globally with around 40% of our CO2 emissions coming from constructing and operating buildings. This means that in the design & construction industry we have a fantastic opportunity to make a meaningful and positive impact. Passivhaus can reduce energy consumption of buildings by 70-90%. This in turn radically cuts CO2 emissions.

The problem and the opportunities are simply too big to leave to the Treehuggers and Energy Geeks, we’ve all got to get involved.

2. EU Legislation

Climate change can be just too overwhelming though. So bringing the focus a bit closer to home, the EU is committed to limiting climate change to a global increase in temperature of 2°C. Recognising that buildings contribute 40% of the CO2 emissions, the EU has drawn up the “Energy Performance of Buildings Directive”. This legislation sets out how buildings across the whole of the EU (including the UK) need to perform in the very near future.

The critical bit to know about is the requirement that all public buildings (owned by central or local government) must be “near Zero Energy Buildings” (‘nZEB’) after 2018 and all buildings are to be “near zero energy” after 2020. So what is an ‘nZEB’? The directive says an ‘nZEB’ is:

…a building that has a very high energy performance. The nearly zero or very low amount of energy required should be covered to a very significant extent by energy from renewable sources, including energy from renewable sources produced on-site or nearby.

The target of “Zero Carbon Homes” by 2016 is the approach taken in the UK to meet the directive’s ‘nZEB’ requirements for houses. Unfortunately, as we are all aware, the definition of a “zero carbon home” is a moving feast that has taken a long time to develop and even now it isn’t entirely clear. Nor is it clear how well a “zero carbon home” will actually perform in use and how the performance will be measured. Added to this confusion the government seems to have changed its mind about which developments are actually required to deliver “Zero Carbon Homes”, so there is a loophole!

And of course there are also all the other building types, particularly those owned and operated by public bodies that are on the tighter deadline to be nZEBs.

This is where the Passivhaus standard comes in and many EU regions are adopting it as the standard to achieve nZEBs. 

3. You can make a difference: Passivhaus delivers

Circling back to climate change, as I mentioned above, the issue is big, often too big to come to terms with in any meaningful way. The easiest reaction is to ignore it and carry on as usual. Or perhaps we make a few minor adjustments to our lifestyle to ease our guilt and concerns. So we need something tangible that we can do and that we know will make a difference. This is what passivhaus offers.

Passivhaus has a 20+ years track record now of delivering buildings that radically reduce energy consumption. It is a standard that works, that can meet the nZEB requirements, and that we can trust. With passivhaus we know we can deliver nZEBs, today.

Certainly designing and constructing passivhaus buildings takes more effort and more attention. It is a very simple performance standard but with a rigorous methodology, so you do have to do the work. However, it’s not just any work, it is meaningful work. You can bring your passion and enthusiasm to your work knowing you are making a difference. Knowing that what you do counts.

With passivhaus you can reliably deliver buildings that consume as much as 90% less energy than comparable building regulation compliant buildings. You can be sure that you are making a very tangible positive impact on the built environment, and in turn on the wider environment. You are helping safeguarding the climate and world we live in, the world our children and grandchildren are inheriting.

And building owners and users love buildings that perform as predicted, or better, and are incredibly comfortable all year round – everyone wins.

Start now

Climate change is a massive issue. In the construction industry we have a fantastic opportunity to positively impact climate change. Passivhaus enables us to act on this opportunity, right now.

Legislation will soon force us to build much more energy efficient buildings. We need leadership before this happens. Now is the time to change the way you procure, design, specify or construct buildings. Now is the time for Passivhaus buildings. (Oh and it’s not just for houses in case you wondered about that.)

Passivhaus gives you the tools to make a tangible difference. There is no need to be an Energy Geek or Treehugger. You can do meaningful work, in the construction industry, knowing it has a direct positive impact on the world today and for the future. You can bring your passion and enthusiasm into your work knowing you are making a genuine difference to climate change. You can take pride in making a difference through your work.

And the time to start is now.

Start by educating yourself so you can take action. Here are some resources to get stuck into today:

I want us, construction industry professionals, to change the world for the better, by changing architecture. Please join me in this mission.

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Elrond Burrell is an Architect, Writer & Speaker with over 15 years experience in designing and delivering excellent buildings. His areas of expertise are Sustainable Design, Passivhaus, Timber construction, and Building Information Modeling (BIM). He is a passionate advocate of these subjects and loves writing and speaking about them, as he often does in the UK and around the world. He is an active member of the UK and Global BIM community and well known on social media for promoting BIM and Sustainable Design.

Elrond is an Associate at Architype Ltd, however, this blog is written in a personal capacity and represents his personal opinions, not those of his employer.

You can also connect with Elrond on Twitter, LinkedIn and Google+.

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8 comments

  • Im my opinion we should care about the people who live inside the houses. Passivhaus is mainly about creating an energy efficient house and doesn’t necessarily create a healthy indoor environment. In the Netherlands their are a lot of problems with ventilation systems in energy efficient houses. I don’t say we shouldn’t care about passivhaus, but when designing by the Passivhaus guidelines you shouldn’t forget the indoor climate and the health of the people who are going to use the house.

    A good reaction is the Active House philosophy, which ames at a balance between energy, indoor environment and the environment. More information at http://www.activehouse.info

  • I’m afraid that I personally consider that we need to exercise care in the adoption of Passivhaus since it requires a building to be effectively sealed and mechanically vented. This requires a consistent and thorough approach to maintenance and the replacement of air filters etc since an ineffective mechanical ventilation system might cause health problems as well as additional condensation related issues. Residential owners generally are not very effective at this!

    • Hi Gareth,

      Thanks for your comment, you’re right that there is an element of mechanical ventilation (with heat recovery) required in passivhaus buildings and filters do require changing. The mechanical ventilation is required for energy efficiency, comfort and health.

      As we move to more energy efficient buildings, this is becoming much more common, regardless of whether or not the Passivhaus Standard is adopted. Fortunately the Pasivhaus Standard does have a very rigourous quality control procedure which is why I advocate that full passivhaus certification is achieved and not some notional “passivhaus principles”. And as mechanical ventilation becomes more familiar, people will adapt and adjust to managing filter replacement.

      However, all that said, passivhaus buildings should still be designed with opening windows, so if the mechanical ventilation system falls out of use for any reason, the building could still be fully ventilated with opening windows. In this case the passivhaus building would at least be no worse for health or condensation issues that any other building.

      And it should be noted that most “naturally ventilated” buildings perform very poorly for both health and condensation risk, it’s just that we don’t monitor or measure these very often or very well to be aware of this. This is a very good article on the subject of ventilation: http://www.katedeselincourt.co.uk/natural-ventilation-does-it-work/

      Best wishes, Elrond

  • We have a number of clients who are very interested in having a Passivhaus but when it comes down to the high cost they change their minds and go for a more cost effective Sustainable Home level 4 or 5. We normally estimate construction costs at £900 to £1200 per square metre [excluding VAT and kitchen fittings] for a sustainable home – so how much more per square metre does it cost for a Passivhaus, including all the kit that has to go with it?

    It would be interesting to know the cost comparison.

    • Dear MJW,

      Costs are often so project specific that it’s very hard to make generalisations, passivhaus or not. Some comments though:

      – Cost is always a matter of priority so different projects will have different costs, and people choose to invest their budget in different aspects of a project. Some like to spend more on a kitchen, others prefer to invest in the building fabric. Code for Sustainable Homes ratings require certain elements to be added / included in the project so the associated costs are unavoidable and can’t be seen as a likle for like comparison with pasivhaus in any case. Passivhaus as a performance standard is less prescriptive, although of course MVHR, triple glazing & increased insulation needed in the UK all have associated costs so these need to be prioritised over other elements. Scale also makes a difference and there are many larger passivhaus buildings (not so sure about houses) completed now that were built to the budget the client set for the project prior to passivhaus being introduced to them.

      – Paul Testa Architects have generously published costings for their Passivhaus entry into the “Self build on a shoe string” competition which you can read about and download from here: http://paultestaarchitecture.co.uk/portfolio/selfbuild-on-a-shoestring/.

      – “The Passivhaus diaries” that Bill Butcher wrote about the Denby Dale home include cost details in this entry that you may find relevant: http://www.building.co.uk/passivhaus-diaries-what-the-denby-dale-home-costs/3141749.article

      – “The Passivhaus Handbook” has a very useful section on costs.

      Sorry I can’t offer anything definitive but that is the nature of construction costs really!

      Best wishes, Elrond