On 1/30/2012 9:57 AM, mcp6453 wrote:
When I watch some home construction and repair shows, I often see them use open
and closed cell spray foam insulation. Often the spray the foam in the attic
between the rafters and in direct contact with the roof. Does the foam preclude
the need for the roof to breathe? When the attic is insulated this way, is the
air flow through the eaves intentionally blocked?


In the last year, I've worked on two house renovations where this was
used. They used open cell on the walls and closed cell on the basement
ceilings and attic rafters. This stuff will really make any new wiring
or plumbing a real chore. It also effectively makes the attic space part
of the heated envelope. Because it seals the house so tightly, they had
to install a whole house ventilation system so the house could "breath".
I'm not sure what the energy savings will be, but my initial thinking
is that it can't be good for indoor air pollution