RiverLife Real Estate


What Is Attic Rain? And Why Is It So Common?

Well, it certainly sounds scary! And it can be expensive to fix. So let’s dive into the causes of and solutions for attic rain.

Attic rain happens when warm, moist air from the inside of your home gets into your attic in the winter and freezes underneath your roof structure. When this ice melts, it can cause damage to the attic insulation and drip down causing stains around bathroom fans, light fixtures or other parts of your ceiling.

Anyone who has lived in Calgary for a few years knows that we can have pretty wild temperature fluctuations. This is why home inspectors in Calgary see so many cases of attic rain here! We can go from -30 degrees (when a lot of moist air is freezing inside your attic) to +10 degrees when all of the ice melts rapidly.

Maybe you haven’t had attic rain but want to ensure you don’t! Every homeowner should be adjusting the humidity levels in their house in winter to mitigate damage to your house. Most houses have humidifiers on their furnaces. If your windows are icing up in the winter, it’s time to turn down that humidity. But humid air is also caused by showers, cooking and simply living in the house! So it’s important to run those bathroom fans and hood fans to get moist air out of the house, especially when it’s extremely cold.

Another important piece of the puzzle is actually poking your head into the attic (or having a home inspector or attic rain specialist do so) to make sure your bathroom vents are properly connected to the roof structure, rather than leaking any air into the attic.

You may be managing humidity well and have all vents property connected but still experience attic rain. This could be due to a combination of inadequate or improperly placed roof vents, poor vapour barrier installation, other gaps, lack of insulation, etc. Every house is different so an evaluation may be needed to establish the best preventative measures for your own roof and attic structure.

When you are buying a property, any licensed home inspector will look inside the attic and let you know if they see evidence of attic rain or any other issues in the attic like improperly connected vents. In today’s market, some home buyers are purchasing without a home inspection. If you decide to do this, I highly recommend still having a home inspection after you take possession. This will allow you to identify any issues and remedy them so you can avoid further problems.

Some of the preventative measures can be quite affordable, especially if you are handy enough to do some of the work yourself. But if there is extensive damage from previous attic rain and you need to remove all the insulation, replace it with new insulation, redo ceiling drywall, add roof vents, etc., the cost could be $10,000+.

Attic rain is so common in Calgary that I would not consider it a ‘dealbreaker’ in most situations. But it is something that homeowners should keep an eye out for and fix prior to listing a house. And it is something that buyers should be aware of and try and negotiate financial compensation for if ongoing attic rain is identified in a home inspection.

If you have questions about attic rain or need a recommendation for someone to come check out your attic, let us know!