Spray Foam Attic Ridge Vent

My thinking is that the ridge vent should be sealed or removed as wind blown rain that enters has no place to go.

Spray foam attic ridge vent.

In typical construction and climates building code tables can be followed when using spf as an insulation and air seal. If you look closely you ll see two exhaust flues on the left side. Spray foam is applied directly where it s needed ensuring that any ventilation vents are left untouched. That means you get rid of all attic ventilation whether it s passive ridge gable soffit vents or active fans.

The two products most often used in an unvented attic assembly are medium and low density sprayed polyurethane foam spf. Building codes provide for the use of spray polyurethane insulation in the foam plastic section. Spray foam is eco friendly non toxic and thermally efficient. All insulation materials require proper venting.

The attic you see in the photo here is a different home but it does have one feature in common besides the spray foam. Inspected a house yesterday with spray foam insulation in the attic. Sorry photo did not come out. This section of the code also describes the use of thermal barriers it seems like the radiation of heat through the windows would make the attic hot.

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. Spray foam from home logic is an excellent insulation type to choose for the attic. The spray foam expands on contact filling up the space where it begins working immediately. Rigid foam and spray foam are two of them.

Windows in a conditioned attic are similar to windows in your home. A ridge vent was still present. Actually you should probably get rid of power attic ventilators whether or not you re sealing the attic but that s another article. Intumescent coatings are not always needed to coat spray foam in the attic in order to meet code thermal barrier requirements.

Heat from the house rises up to the attic but when there isn t one the heat rises up to the roof. The installer sprayed foam directly on the metal flues. You should never do this. Cathedral roofs especially need a lot more insulation between the ceiling and the rafters because there usually isn t any attic space.

One of the most common reasons to put spray foam on the roofline is to avoid having to air seal the attic floor because the attic is connected with the air in the house and indoor air is more humid than outdoor air which can cause moisture problems.