Proper Airflow With Attic Insulation Baffles

Proper airflow through attics is essential to prevent heat accumulation, and humidity dripping on the ceiling. The air usually enters through vents in soffits under the eaves, passes through the attic space and naturally exits through roof vents, although fan-assistance may be necessary.

It’s extremely important to keep the soffit vents clear when viewed from inside the attic. The commonest cause for blockage is ceiling insulation lying loose after work done in the roof. The solution lies in fitting attic, also called rafter baffles to ensure this does not happen.

What Do Attic Insulation Baffles Look Like

Prefabricated attic insulation baffles are made from hard-core waterproof foam, and come in convenient lengths. They work a little like three-sided chimneys drawing the air from the soffits into the roof space. Although you could also make your own from plywood , if you prefer a greener, more renewable alternative.

The baffles fit between the rafters from the upper edge of the soffits, for a few feet upwards. This should be sufficient to prevent insulation off-cuts and other debris obstructing the airflow. But you only need install them between pairs of rafters straddling soffit vents.

Installing Attic Baffles If You Want to D.I.Y.

1… Determine the number of soffit vents you want to protect. Don’t simply count them from below. Some cowboy roofers install dummy ones and they get away with it. Pop up into the attic and confirm (a) how many there are, (b) you can get to the soffit vents and (c) the spacing between the rafters.

2… Obtain sufficient material, not forgetting goggles, gloves, clean dust mask, and coverall to avoid allergic reactions. Get back in the attic, peel away the insulation as necessary, and fit the rafter baffles in place. Power-staple them securely, ensuring a snug fit over the soffit vents.

3… Replace the insulation carefully, ensuring a tight fit against outside edges, and a decent overlap at joints. Small gaps can allow a surprising amount of warm air to escape from the living space below. You could soon notice the difference in your energy bills.

If You Dislike Mucking About in Attics …

If you dislike wearing goggles, gloves, dust masks and coveralls, and have other things to do on your weekends, give Valiant Exteriors a call on (403)829-1661 in Calgary when convenient. We are local experts on all aspects of roofing and ventilation, and would love to be able to assist.