Attic Cross Ventilation

Ventilation of attic spaces is required by most building codes as well as by roofing material manufacturers and the national roofing contractors association nrca.

Attic cross ventilation.

The soffit vents are now installed but you still need to make sure there s no insulation blocking the new vents. In other words the entire vent opening doesn t count as vented space. In the summer natural air flow in a well vented attic moves super heated air out of the attic protecting roof shingles and removing moisture. If there s blown in insulation like ours rake back the fluffy stuff with a 3 or 4 ft long 1 x 6 or use a garden rake or hoe.

Intake vents located at the lowest part of the roof under the eaves allow cool. Most building codes require a ratio of 1 150 ventilation space to attic floor space. That said air resistance and interference such as vent grates reduces the area of true ventilation. Enclosed attics and enclosed rafter spaces formed where ceilings are applied directly to the underside of roof rafters shall have cross ventilation for each separate space by ventilating openings protected against the entrance of rain or snow.

You can also contact your local municipality to check on building code in your area. Attic ventilation works on the principle that heated air naturally rises primarily utilizing two types of vents. The insulation will resist heat transfer into the house.