Last week was quite eventful. Mike’s team finished the tin roof, started with installation of airtightness membrane to underside of roof structure and we had a wood stove installed.
Being a passivhaus with low space heating requirements, our house won’t need much heat to keep it comfortably warm, so putting a wood stove in is a bit of a luxury rather than necessity. The intention is that it will provide bulk of the space heating, topped up with towel rail in bathrooms. For simplicity, we have not coupled it with back boiler to heat water (hot water will be generated via heater with air source heat pump). There have been a couple of technical challenges to overcome – airtightness and air supply. We have used Morso S11-42 stove (with optional airtightness kit) in combination with Poujoulat Efficience triple wall flue to give us a completely room-sealed system. The external cavity of the flue supplies fresh air in from outside directly to the stove, and the inner flue takes the hot air out. This ‘pipe in a pipe’ system also means that there is only one penetration through the building fabric. The flue came with a proprietary airtightness plate with a flexible seal, the airtightness membrane will be taped to it.
It was exciting to see the first fire lit – installation crew from Poujoulat (flue) and Prince&Pugh Knighton (stove) did a great job. Will just have to be careful with keeping the fire under control with all that exposed straw inside!
We will be opening the house up as part of international passivhaus open days on 11 and 12 November – follow this link for more information.