With the world's life-support systems in crisis, almost anything we do now, we need to have some part of our mind on the effect on the environment - the wider world. And of all the things we do, construction is likely to have the greatest effect, so the attention needs to be all the more acute.
We advocate Passive House principles wherever possible - a fabric-first approach with deep insulation, detailing to avoid "thermal bridges", good airtightness with heat-recovery ventilation and careful modelling of the heat gains and losses. To these classic principles we can now add use of benign materials and low/zero carbon energy sources.
We won't get it perfectly correct (if there is such a thing). Some (not all) of the things we need to do differently cost more - especially up front. Some of the methods we use to get good technical performance, risk harms elsewhere or down the line. Will we want to trash existing fittings - or whole buildings - just to replace them with somewhat better-performing versions? It is an evolving discipline, but some principles are emerging.
Low-carbon retrofit
External wall insualtion
Pre-construction airtightness testing
Pre-constructon brickwork analysis
Pipe and duct nsulation
Existing window relocated
External wall insulation
Internal wall insulation - wood fibre
Solar therma; collector
Parge-caoting for airtightness
Thermally-broken structural connection
Roof extension - to protect external wall insulation
An attempt to retrofit a traditionally-built Liverpool house of a common construction type to as high a standard as possible. The techniques used include:
* External insulation at the rear (a safer way to achieve high insulation, but not suitable where we would want to maintain the appearance.
* Internal insulation at the front - which take up space from the room and can involve risks of condensation.
* Using low-carbon materials where possible - such as wood-fibre-based insulation. As well as causing less harm to the environment, these are usually more pleasant to use - and to alter in the future if that is ever needed.
*Lots of PV panels on the roof. We expect the house to create more energy than it uses over a year.
* Solar thermal vacuum tubes, which should provide all the hot water in summer, and reduce the energy needed to heat it even through the winter.
* Attention to air-tightness combined with a comprehensive ventilation system, which recovers heat from the stale air and feed into all rooms - keeping air fresh and reducing risks of condensation, mould and diseases.
(Links to BIMx - 234Mb)
Phase-change material wall/ceiling lining
Rooftop PV installation
Framing configuration for superinsulation
Internal and external wall insualtion,
roof insulaton and solid floor treatment
A selection of environmental features from other projects.
In 2005 the proposal to widen the western end of Edge Lane to a dual carriageway and demolish hundreds of houses in the process was met with opposition from the residents. This alternative demonstrated that the road could be reconfigured so as to free u p the congested junctions and carry the same volume of traffic more safely without the loss of any occupied houses (or other businesses).