Attic insulation

What is an attic?

It is the space that is between the ceiling of your home and the roof.

Attic problems include:

• Water infiltration due to ice build-up on the roof edge
• Seepage in the walls
• Peeling paint
• Spots on the top of the walls and ceiling
• Mold appearance near the top of the walls
• Premature wear on roof shingles

The solution

We must ensure that air can circulate freely and sufficiently in the attic. You may have noticed that soffits are perforated with many small holes - it's not just for looks. It is through these holes that air must enter and then move out again through roof vents. See the graphic to the right.

Why should air circulate in the attic?

• It reduces overheating in the summer, which helps extend the life of roof shingles.
• It may be that after taking care to seal air leaks from the house, water vapor can still penetrate the attic. The air circulation then constitutes the second line of defense against it.
• A well ventilated roof is cooler and thus prevents ice buildup along the eaves, which causes water seepage during a thaw.

It is therefore important to ensure that existing vents (soffit, gable maximum or grid) of the roof are working well and not blocked by insulation.

Even if the roof is sealed, the National Building Code recommends a minimum of ventilation. It is recommended to consult a specialist to determine the type, number and location of vents to be installed.

While vents are important, they alone cannot solve condensation problems. Air leaks need to be sealed first.