Roof Space Ventilation

Too many people believe the importance of roof ventilation is to increase energy efficiency during the summer.

Roof space ventilation.

Touch your ceiling on a warm sunny day. Ventilating attic spaces is often viewed as a technical requirement for steep slope roof assemblies as well as a building code requirement. To calculate the amount of ventilation you need for your home visit gaf s ventilation calculator now. Ventilation of attic spaces is required by most building codes as well as by roofing material manufacturers and the national roofing contractors association nrca.

Here are four signs of an unventilated or under ventilated attic. Intake vents located at the lowest part of the roof under the eaves allow cool air to enter the attic. Soffit vents sometimes known as eaves vents. A hot ceiling tells you that the attic is acting like a solar oven.

The air gap dimensions shown on the drawings are the minimum widths required for clear continuous ventilation air paths at the eaves. Hot air exhaust vents located at the peak of the roof allow hot air to escape. So the decision to vent an attic space is not dictated by building code. Ventilation at the eaves roof voids must be ventilated in order to stop warm air condensing on cold surfaces.

If you need soffit vents the good. Good roof ventilation can do this but shingle color sun exposure and insulation are exponentially more important to overall energy efficiency than ventilation. Most building codes require a ratio of 1 150 ventilation space to attic floor space. Often called a felt lap vent because they are mostly fitted to older roofs with bitumen felt.

However since the 2009 edition of the irc attics can be designed to be either vented or unvented. Ventilation can be accomplished using various products and techniques. Bathroom vent felt lap vent. Look at your eaves and roof.

You can see these fitted to most modern houses and are. Vent the roof deck. Attic ventilation works on the principle that heated air naturally rises primarily utilizing two types of vents. Condensation encourages rot and mould growth.

Before we explore how to ventilate an attic space it is prudent to understand how much ventilation is needed. If you don t see any attic vents on the roof or in the eaves you need to add some. It really is a design choice. 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.