Roof Space Ventilation

Proper attic ventilation can help reduce the load on your air conditioner.

Roof space ventilation.

A hot ceiling tells you that the attic is acting like a solar oven. Too many people believe the importance of roof ventilation is to increase energy efficiency during the summer. Soffit vents sometimes known as eaves vents. Often called a felt lap vent because they are mostly fitted to older roofs with bitumen felt.

Most building codes require a ratio of 1 150 ventilation space to attic floor space. If the attic space is going to be conditioned either for living or mechanical purposes or if a home design calls for a vaulted ceiling provision r806 3 in the international residential code calls for the roof deck above the space to be vented continuously from the eave to the ridge. Ventilation at the eaves roof voids must be ventilated in order to stop warm air condensing on cold surfaces. Ventilation can be accomplished using various products and techniques.

Good roof ventilation can do this but shingle color sun exposure and insulation are exponentially more important to overall energy efficiency than ventilation. Vent the roof deck. Here are four signs of an unventilated or under ventilated attic. If you don t see any attic vents on the roof or in the eaves you need to add some.

Let owens corning roofing help you calculate exactly how much ventilation you will need for a healthy and balanced attic with our 4 step ventilation calculator. To calculate the amount of ventilation you need for your home visit gaf s ventilation calculator now. Attic ventilation works on the principle that heated air naturally rises primarily utilizing two types of vents. Touch your ceiling on a warm sunny day.

Calculate or enter the square footage of the attic or area to be vented. Ventilating attic spaces is often viewed as a technical requirement for steep slope roof assemblies as well as a building code requirement. If you need soffit vents the good. Intake vents located at the lowest part of the roof under the eaves allow cool air to enter the attic.

Look at your eaves and roof. So the decision to vent an attic space is not dictated by building code. However since the 2009 edition of the irc attics can be designed to be either vented or unvented. Before we explore how to ventilate an attic space it is prudent to understand how much ventilation is needed.

Bathroom vent felt lap vent. You can see these fitted to most modern houses and are. The air gap dimensions shown on the drawings are the minimum widths required for clear continuous ventilation air paths at the eaves. Condensation encourages rot and mould growth.