Passiv house costs.

[garrymartin]

38 minutes ago, -rick- said:

A lot of custom one-off homes will tend to be in the more expensive as the customers will want nice things like big windows, overhangs, lots of corners and detail or simply to squeeze a lot into a difficult site. Meeting the passivhaus standards then will add a lot more cost than a simple box.

Spot on. Passivhaus is only of near-equal cost parity if the building was designed to be Passivhaus from the beginning, including principles of form factor. If someone has designed a home, and then tries to make it Passivhaus, then you are almost in retrofit territory, which of course costs more.

 

18 minutes ago, saveasteading said:

I was thinking of one-offs as most on BH are.

I think you can do one-offs too at significantly less than 30% increase in costs, but as above, you need to design from the outset.

 

The garage door is a great example earlier in this thread. It looks like the architect/designer didn't consider this at the outset, and possibly made the fire *and* airtightness barrier/boundary the same, causing the requirement for an airtight and thermally efficient fire door, which was very costly. Separating those elements (fire/airtight) at the design stage may have resulted in signficantly less cost. It may not have been possible given site or design constraints, but just one example.