Conditioned Attic Spray Foam Insulation
My original plan was to build a conditioned attic and place 1 5 of foam xps board r7 5 installation on top of the roof deck and fill the old true 2x4 rafters and rafter walls with closed cell insulation and if able attach 3 of foam xps board r15 to the rafters in the attic.
Conditioned attic spray foam insulation. Nothing unusual about that. Spray polyurethane foam is a chemical product that is created by two materials isocyanate and polyol resin that will react with each other when they are mixed and will expand up to 30 to 60 times its liquid volume as it is sprayed in place. Earlier this year i got a question about a home that had spray foam insulation in the attic. Furthermore in many zones an unvented attic featuring r 22 spray foam insulation installed will outperform the conventional high performance r 51 attic.
This will allow for optimal operation of your hvac equipment as well as aid in early detection of situations such as roof leaks and wind driven moisture intrusion. Using icynene spray foam as your attic insulation will turn your attic into a conditioned space. 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 alternative to traditional building insulation fiberglass can be applied into wall cavities holes concrete slabs and even onto roof tiles and.
Open cell spray polyurethane foam ocspf or closed cell spray polyurethane foam ccspf insulation is sprayed along the underside of the roof sheathing to provide a unvented insulated and conditioned attic space or roof assembly that can be resilient durable and efficient in all climate zones. Taking a look at both approaches a title 24 prescriptive attic provides higher levels of insulation to reduce the amount of heat loss and gain. When we seal the attic with spray foam it s as tight as a butter tub. The insulation reduces wildly high temperature spikes and so the attic becomes a conditioned part of the home like any other room.
When spray foam is installed on the underside of the roof deck the attic space is insulated from heat that otherwise would be entering the attic. It has the highest r value of any insulation material is a vapor retarder and provides a tight air seal. 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. Foam insulation above the roof deck to keep its temperature above 45 f throughout the year or spray foam insulation under the roof deck to keep interior moist air from contacting it.
It will also help keep any duct leaks within the conditioned space of your attic.