Ventilated Or Unventilated Roof

A properly functioning un vented roof.

Ventilated or unventilated roof.

The energy savings touted by unvented attics can be as high as 20. Ventilated roofs remove moisture from roof cavities structural members sheathing and insulation. In an un vented roof foam can serve as the air barrier and vapor retarder and prevent moisture from getting in to the roof cavities. Unventilated attics can help to mitigate energy loss through leaky ducts or ceiling fittings.

If you don t see any attic vents on the roof or in the eaves you need to add some. Unventilated or poorly ventilated attics don t have an escape route for the heat that builds up. Alternatively an unventilated pitched roof may be designed. The enclosed void of a warm pitched roof does not require to be ventilated.

This is known as a fully ventilated airspace as opposed to an unventilated air space. A properly insulated ventilated roof can help to control or prevent the formation of ice dams. Because the sheathing is kept cooler roofing materials tend to have a longer life span. Your roof vents may not look anything like the ones shown in this article.

If you don t want to use sips or nailbase read this article tolearn the four basic approaches to insulating unvented roof assemblies. Look at your eaves and roof. Good roof ventilation can do this but shingle color sun exposure and insulation are exponentially more important to overall energy efficiency than ventilation. This buildup of heat can damage your shingles from the inside out.

Unvented roof assemblies should be insulated either with air impermeable insulation rigid foam or spray polyurethane foam or with a combination of foam and air permeable insulation. The principle applied here is warm moist air rising from below is allowed to permeate through the roof membrane removing the need to fully ventilate the roof. However if moisture is able to enter the unvented attic space it may lead to roofing panel issues. Here are four signs of an unventilated or under ventilated attic.

An evenly vented roof will allow the hot air to escape keeping your roof and attic cooler. These roofs keep your home cooler during the hot summer months. Foam insulation can play an important role in both vented and un vented roof assemblies.