In an attic the eaves are one of the most critical places to get good coverage with the foam.
Attic closed cell foam under blown insulation.
If you leave the existing insulation in the attic it interferes with the foam installation.
Spray foam provides the highest r value while open cell spray foam has about an r value of 2 2 to 3 5 per inch closed cell spray foam has about 6 7 per inch.
Open and closed cell foam insulation use a blowing agent to forms the cells within it.
Yeah if you do a really good job raking the insulation back you can still do a good job with the foam.
This form of insulation is commonly known as two pound foam as it is a rigid insulating material that requires a thickness of 50 mm when applied in the home.
In general most closed cell foam and many open cell foam products can be installed without the need of an intumescent coating in an unvented attic and therefore can go bare provided a drywall ceiling 15 minute thermal barrier directly below the attic exists.
Earlier this year i got a question about a home that had spray foam insulation in the attic.
Typically this foam s natural color is yellow when applied in insulation.
Open cell foams use water as a blowing agent.
Because it requires professional installation closed cell foam insulation is pricey but it offers r 6 thermal value for every inch of thickness.
However in a traditionally insulated attic insulation on the ceiling the attic is vented.
One huge benefit of the spray foam insulated attic is that conditioned air leakage from the ac furnace duct system is contained and used to condition the attic.
This medium density spray foam is a closed cell spray foam that is typically used where there is the need for r value insulation per inch possible.
But it s harder and the chances of success are lower.
Nothing unusual about that.
Closed cell foams use enovate also known as 245fa which is.
This type of spray foam offers the specific benefits of continuous insulation interior wall cavity fill and unvented attic applications.
The foam usually polyurethane is sprayed to fill cracks and gaps in the attic to form a hermetically sealed barrier.
Whereas blown in insulation works by filling the.
A lot of builders and homeowners are going with spray foam insulation because of the airtightness benefits but then the questioner mentioned that the spray foam contractor had intentionally left big holes to the outside by not sealing the gable vents.
Open or closed cell spray foam is applied to the underside of the roof sheathing and additional fiberglass or cellulose insulation is blown in as a cost saving method for meeting high insulation requirements and filling in the cavity space between the rafters to the ceiling deck.
