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
- 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.
- 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).
- 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).
Please Connect With Me
- Subscribe, rate and review the podcast in iTunes
- Like our Facebook page
- Follow us on Twitter
