Dealing with Attic Rain

What is Attic Rain?

Attic rain can occur when there is a build up of moisture, usually frost, in the attic. Some condensation or frost in the attic is common, but never in large amounts. In small amounts, this frost just vaporizes before it can cause damage. In large amounts, the frost will melt and start to drip in the attic. This can cause stains on the ceiling and even dripping inside light fixtures.

Details Insulation in Edmonton explains more:

What causes attic rain?

Everyday activities inside the home like doing laundry and cooking can leak into the attic. When it’s wintertime, the moisture turns into frost and it can start to build up. The longer the cold weather lasts, the bigger the frost accumulation. When it warms up a little, this frost melts and causes rain inside your attic.

Attic rain can also be caused by improper sealing of the chimney and vents to the outside as well as disconnected vents from your kitchen appliances, dryers and bathroom leaking moisture into the attic. High humidity in the home, holes in vapour barriers in the attic or inadequate or missing insulation in the attic can all contribute to frost accumulation and attic rain.

Bathroom fan leaking

House pressure can also affect frost build up. Picture your entire house acting as a chimney, trying to vent warm air from the bottom to the top. The uppermost level will always get more frost than the other levels. If your home has a combustion air duct connect to a return plenum, the house will pressurize every time the furnace kicks in, increasing the negative affects of attic air leaks. Read more about how pressure and holes cause attic rain.

Unbalanced ductwork can also cause pressure problems in the home. If there are too many return air openings in the basement ductwork, it will experience negative pressure when the upstairs levels have positive pressure. Sealing up any holes and gaps in the ductwork can help decrease attic frost.

Signs of attic rain:

Water damage on the ceiling is a big tell-tell sign of attic rain. You might notice the staining around the attic hatch, light fixtures or the bathroom ceiling vent. Take a peak in the attic and look for any rusting nails or screws, water marks on the framing and/or staining of the insulation. From the outside, attic rain can stain the area below your soffit.

How to fix attic rain?

Most often, the most important step is to eliminate air leakage into the attic but inspecting and sealing all possible areas where air can escape, and repairing any vapour barrier deficiencies.

First step is to book an attic inspection – this takes about one hour on site, and we perform a basic infrared scan, look for obvious areas of leakage, and test exhaust fans. At this point we’re able to propose a recommended scope of repair and provide an estimate.

Second step is to move forward with the repair, which can sometimes be as simple as repairing exhaust fans, then topping up the insulation that was disturbed in the process. If the fans don’t appear to be the primary source of the air leakage, or the insulation was/is wet, then the insulation should be removed. Once the insulation removal is complete, we air seal the floor of the attic, and make any necessary repairs. Depending on age and condition of home, the air sealing may include the use of closed cell spray foam insulation to ensure a perfect seal.

Third step is to test the repair work, before adding in new insulation. We work with a third party building performance contractor to pressurize the house with a blower door, and then inspect with infrared camera to ensure that the attic is perfectly sealed.

Once the inspection is complete, a new layer of blown insulation is added.

Insulation Contractors in Edmonton

Whether you’re looking for spray foam insulation, an attic insulation upgrade, attic insulation removal, blown in blanket system, batt insulation, or poly vapor barrier, Details Insulation can do it! If you think you might have an attic rain problem, contact them right away!

Contact Details Insulation!


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