Attic Rain and Its Effects

Calgary has some of the wildest temperature changes in all of Canada, with last week going from minus 40C to 2C in a matter of 3 days. An ongoing issue homeowners have here is the phenomenon known as “Attic Rain”.

What is Attic Rain ?

When the snow builds up on the roof, and doesn’t melt, frost builds up inside the attic as well. Roof vents stay covered, not allowing warm moist air produced from showers, cooking, etc to properly escape the home. Fast forward a couple days, and it’s now on the plus side, and the sudden mass melting causes the frost to “rain” down in the attic. This is a ventilation problem, as the lack of removing this moist air causes the problems.

Issues caused by Attic Rain

Some of the issues seen as a result of attic rain are : 

Staining– water marks on the ceiling, often appearing near a fixture.

Sagging roof –  from the weight of snow, and subsequent rot.

Mold – Mold is a toxic fungus that is hard to remove, and is dangerous as it produces toxic spores that are then breathed in by the homeowners.

Leaks – Water running down can come in contact with areas such as electrical components.

How to prevent Attic Rain

As I mentioned above, Attic rain is primarily a ventilation problem with moisture being the culprit. There are a few things as a homeowner that can go a long way to prevent or at least slow or ease the amount building up.

Always use the bathroom fan and leave it on for 30 minutes after bathing and showering.

Ensure that the fans are actually ventilating to the outside properly. I have seen numerous cases where the bath fan is not connected to the gooseneck on the roof, allowing all the humid air to pour directly into the attic.

Run the kitchen fan while cooking.

Keep your humidifier set to low during the winter.

If your home has a whole home ventilation system, turn it on daily for 20-30 mins.

Confirm you have enough roof vents. Soffit vents under your eaves bring in fresh air, and it is drawn out by roof vents, creating a properly ventilated attic space. Without the correct amount of roof vents, this ventilation suffers.

Going Forward

Remember, properly ventilating your attic helps keep the moisture and temperature in check, and in return will go a long way in preventing Attic Rain and its damaging results.

Call me anytime at Pegasus Home Inspections Ltd. to discuss any issues you may find in your attic, or if you see signs that you want to investigate. We can get to the bottom of your problems and guide you in the right direction, ensuring your home is safe, and free of issues that cause future damage.

Stay warm and dry !