Because basically now that attic is a conditioned space.
Spray foam attic dump zone.
Intumescent coatings are not always needed to coat spray foam in the attic in order to meet code thermal barrier requirements.
We mean that literally by the way.
Nope you absolutely do not need to ventilate a spray foam house and here s why.
Earlier this year i got a question about a home that had spray foam insulation in the attic.
Although spray foam insulation has been in use since the 1940s primarily for aircraft for the past 30 years continual product innovation has seen the increased adoption of spray foam insulation in residential and commercial construction.
The rapid growth of sprayed foam insulation in building construction thanks in part to its immediate and long term.
It s quick and easy to do.
Nothing unusual about that.
I have a spray foamed attic.
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.
Attics with spray foam insulation are so cool.
When you insulate the top of your attic with spray foam you re bringing your attic into your home s envelope as a result you can reduce the temperature in your attic by a lot anywhere from 120 degrees to around 95 during peak summer.
Spray foam estimated r 30 was applied at the roof structure of an attic in a home located in climate zone 6.
Sealing the top of the house keeps the air you paid to heat and cool inside your home.
The unvented attic space is considered the most effective and up to date building practice particularly by the spray foam industry.
It s terrific because it s pretty much the same temperature as the rest of the house all the time.
No indications of moisture damage were observed.
It s just a pathway.
While this type of attic system is the most commonly used system in the u s it is not the ideal system when it comes to energy efficiency indoor comfort and.
The role of open cell spray foam.
Normally in occupied areas all spray foam must be covered by a 15 minute thermal barrier such as thick drywall per code requirements in irc section 316 4 and ibc section 2603 4.
All sheathing locations that were measured were less than 18 mc.
It has a relatively high vapor permeance 3 perms at a thickness of 6 allowing water vapor to migrate to the roof decking at night and back into the attic air in the daytime.
Using spray foam insulation in an attic is a popular energy saving project.
Open cell spray foam insulation doesn t store the moisture.