loft vent in insulated but not conditioned space
New, 1.5 story AFrame house with SIP construction, including 10″ thick SIP panels for the roof.
There is usable loft/attic space that will be used for storage only.
In order for the loft not to be counted as living space by the town (and therefore taxed as such) we had to insulate the attic floor to R60 and close it off from the rest of the house. Access through an insulated hatch. So the loft is insulated both from above and below.
The architect drew one large vent in place of one of the gable end windows. The house is on the shore of Georgian Bay (Ontario, Canada). Cold low humidity in winter, high humidity in summer.
Is there any reason NOT to close off the attic vent in winter, keeping the house just that little bit warmer with less heat loss? Do I have to worry about condensation on the underside of the roof SIP panels?
Replies
Did your builder do a blower door test? If there is no leakage through the attic hatch, and it is insulated I would think that there would be so little heat in going into the loft that you don't need to worry about closing off the vent.
I'm the builder :) Yes, we did a blower door test, tighter than R2000. But still...