One of the great things about bringing a group of neighbours together for an Assembly process is seeing the sharing, learning and friendly connections that take place independently of the facilitated process.
Chris Gathercole has been a diligent proponent of improved building efficiency since we first met early in 2021. After meeting other assembly members, he generously extended an invitation for small groups to visit his home to learn about the Passivhaus retrofit process that he and his wife had undertaken. Here we hear from him and from Chris Hill who was one of the visitors.
My wife and I moved into our 1979 house in 2019 and found it was a great opportunity to improve its energy efficiency. We had been interested in doing our bit to mitigate climate change since visiting the Centre for Alternative Technology (CAT) near Machynlleth in the 1970s. Over the years we learned about retrofit. Especially inspirational was a home visit arranged by Cumbria Action for Sustainability (Cafs) to learn about one family’s experience. Now in 2023 we realised that our experience might be of interest to members of Dyffryn Peris Climate Assembly. Our invitation said: ‘We will cover planning the retrofit, finding a designer and building trades people, insulation, air tightness, ventilation, heating, water vapour permeability, cold bridging, solar panels, battery storage, controls, Passivhaus and other standards, and more. We plan to schedule a two hour visit for up to six people in early January.’ 14 people expressed interest so we had sessions for three groups at our home looking at what we did to improve the sustainability and comfort.
We started each visit with a tour, first outside, to look at the insulation, air source heat pump, solar panels and battery.
Then, inside, we explored the mechanical ventilation and heat recovery system, underfloor heating, triple glazed windows and doors.
As we went along there was lots of discussion about the visitors’ experiences. Several had had a go at retrofitting their own houses. Discussion was lively especially on the horror stories about cowboys in the building industry and the difficulty finding designers for retrofit for sustainability as well as tradespeople knowledgeable and experienced in such retrofit. Damp is a common and challenging problem often found in older houses with stone walls so prevalent here.
The building industry has a long way to go to adapt its traditional ways to the new demands for higher standards of building sustainability. Clearly a lot of training and retraining is needed. In addition we need greater awareness among householders so people like ourselves know what to ask for. Without the demand, the industry will be reluctant to change. CAT has done a great job in raising awareness as well as training for professionals but we need much more local training and awareness raising such as organisations like Cafs provide if we are really to make every house energy efficient, comfortable and healthy to live in. Things are changing though: technology, materials and equipment, government policies and grants, have all developed even in the two years since we finished the main stages of our retrofit. The Net Zero Centre at Penygroes which will be training building tradespeople will give a major boost to creating the necessary workforce. We will still need a vigorous programme for raising awareness among the wider population.
Chris Hill was one of the Assembly members that visited Chris Gathercole’s home
Dyffryn Peris climate assembly members were invited to see first hand what is possible when retro-fitting an existing property to Passivhaus standards.
Chris Gathercole, one of our assembly members hosted three groups of visitors to showcase what he achieved when renovating his bungalow and to explain the process, benefits and some of the methods employed in retro-fitting an existing building.
Every retro-fit project has to be tailored to the specific building, be it a traditional stone built cottage, bungalow or whatever? How and when the house was built will also have a major influence on the approach to the project, as building standards and methods of construction have varied widely over the years.
The main principles to Passivhaus are to insulate the building to a very high standard, including the use of insulated doors and windows, usually triple glazed. Eliminating thermal bridges to the outside and making the building air tight, so you are not losing heat created inside the building to the outside. Another key factor is MVHR (Mechanical ventilation heat recovery) This is a system whereby air inside the building is constantly being exchanged via filtration and a heat exchanger that warms the air that is being drawn into the building by the air that is being expelled.
Chris also installed solar PV panels and an air source heat pump to compliment his efforts on carbon emission reduction.
It was quite apparent that forward planning and viewing the project from ‘a whole house perspective’ is crucial.
Passivhaus retro-fits can also be carried out in stages so you don’t have to get it all done in one go. You don’t even need to get to the standard where your property can be certified as a Passivhaus. It may not be possible or practical to reach certification standards on some buildings. However, the closer you can get to these standards the better; both from a carbon reduction standpoint and becoming far more economical to run.
Chris’s house was certainly warm, comfortable, quiet and very economical to run.
A big thank you for inviting us all and sharing the experience with us.
Some Useful links for those interested:
https://www.passivhaustrust.org.uk
https://cafs.org.uk/
https://www.greenbuildingstore.co.uk/
We are grateful to Chris Gathercole for all his enthusiasm and support for the GwyrddNi Dyffryn Peris community. We send our deepest condolences to his family in their bereavement.
– March 2025.
