Spray foam insulation is broken down into two categories open and closed cells.
Closed cell vs open cell foam in attic.
Open cell has an r value of 3 7 and closed cell has an r value of 6 5 based per inch of installed spray foam.
The entire home has open cell foam and there s no attic with a complete vapor barrier.
Benefits of closed cell foam closed cell foam is the best choice for robust insulating where space is an issue as it can achieve 2x the r value of open cell inside a standard wall.
The insulation is blown into the wall or attic one layer 1 at a time.
Open cell foams use water as a blowing agent.
Its rigid nature also adds to the structural integrity of.
This describes the way that the foam looks once solidified.
Closed cell foams use enovate also known as 245fa.
Open cell foam insulation in my attic area.
Exterior has a 1 2 thick drainage board and building paper against the sheathing where the thinstone veneer is attached to this specialized system designed for stone.
The home builder used 1 2 polyisocyanurate as an interior vapor barrier under 1 2 drywall.
Here s a quick summary of open cell vs closed cell foam strengths and the best applications for each.
Open cell is created through lower pressure and as a result has a more open structure.
Open and closed cell foam insulation use a blowing agent to forms the cells within it.
Most insulation contractors are recommending open because it s cheaper and also because if i go with closed cell and the roof leaks it will not penetrate the insulation and could remain stuck between the sheathing and the insulation and could rot the wood and or travel to a more hidden spot of the roof or attic causing worse problems that are.
Some say use open that way you can see a leak before it does any damage others say use closed so any water damage should run off under your roof shingles.
It s expanding properties ensure that it covers every little crack and hole but even with that ability it still needs to be installed correctly.