Old house retrofit using Demilec foam in wall and polyiso board OK?
I live in the Western Upper Peninsula of Michigan in a 100 year old house. I have taken the inside down to the studs. I have removed all exterior wood siding. Western exposure was taken completely down to the studs. Plywood sheathing installed, All other exposures kept 1 by sheathing boards, I have covered exterior with 1 inch polyiso board with fiber cover (warm wall).
All boards taped and caulked at joints. Insulation board then covered with Tyvek. Metal flashing above all openings. RainSlicker on top of Tyvek to provide a separation for ventilation of the rainscreen of wood siding. I want to put a 3/4 layer of foil polyiso on the inside beneath the sheetrock. I plan on using energy recovery ventilation. Is the interior poly iso an issue? I have tried to be meticulous in the sealing around windows and doors.
It is my understanding that I really do not need a vapor barrier as most moisture movement is due to air flow and that is unlikely in a foam filled cavity.
Posted May 28, 2010 10:49 PM ET
Edited May 29, 2010 4:15 AM ET
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