Dormer house question

budget1984

We built dormer house in 2012. During the summer upstairs gets unbearable warm n in winter it's impossible to heat. Our walls are insulated but we think attic may need another layer of insulation. Would insufficient attic insulation be the cause of coldness upstairs in winter

Lumen

What was the final air permeability (blower door) test result?

P2C

The weak spot might be the rafters and rakes. Get a thermal camera on the roof. There could be spots where there’s no insulation and that could be the cause of the problem. A dormer is hard to fix on a retrofit. Not as simple as adding extra in the attic.

I build a dormer in 2010 to a A standard for an example. I went for natural insulation as wife and kids are asthmatic . 400mm of cellulose in the attic
I added or increased the size of my rafters and i think it was 300 mm cellulose on the rafters and cross battened with 75 mm sheep’s wool and the same on the rakes

budget1984 wrote: »

We built dormer house in 2012. During the summer upstairs gets unbearable warm n in winter it's impossible to heat. Our walls are insulated but we think attic may need another layer of insulation. Would insufficient attic insulation be the cause of coldness upstairs in winter