Rectory Cottage: Deep Retrofit
This property was unlovely when purchased for the purpose of achieving a Passivhaus standard retrofit by two clients with the determination to achieve 'EnerPHit' certification.
The work involved:
• gutting the building entirely
• relaying a highly insulated floor slab
• fitting thick external wall and roof insulation
• installing triple-glazed doors and windows
• making desired internal layout changes
• replacing all services and
• installing underfloor heating + MVHR
Perhaps the best explanation comes from the clients, in this tribute:
"We had a challenging project: a retrofit to passivhaus standard of an old stone property requiring planning approval in a National Park and local conservation area.
Furthermore, as I had the time and the interest I decided to “project manage” the work myself, so Simon also had to deal with an amateur, which he did with skill and tact.
Simon delivered: the finished building achieved certification to the PassivHaus retrofit standard, and what’s more important the actual annual energy use over the last six years is slightly lower than the design specification, even after allowing for warming.
Happy clients ! "
This is how a lot of the existing housing stock will need to be upgraded if we are to reach 'net zero'.
Starting it now, we would almost certainly have used a heat pump, instead of a gas boiler, as the national grid becomes decarbonised.