Since basement renovations are one of the most popular types of renovations that the contractors at Menno S. Martin undertake, we figured it would be helpful to write a blog post about proper basement insulation.

Too often, we find that many basements are lacking the proper insulation – regardless of whether they’ve been previously finished or not. Whether or not your basement has been properly insulated generally depends on the age of your home. If your basement hasn’t been insulated properly or is lacking insulation altogether, having it insulated by professionals while they’re renovating the space can save you a lot of time and hassle.

Why Proper Basement Insulation Matters

The first thing to consider before insulating your basement is to confirm there is no water leaking in. No amount of insulation will help stop bulk water infiltration. We dealt with some tips to deal with water infiltration in a previous blog post about preparing your house for winter. In a nutshell you should direct as much surface water away from the house as possible. This means extending downspouts, keeping eave troughs cleaned out and sloping the grade away from the house walls.

Now that you have dealt with any water issues you can focus on the insulation. The best way to insulate a basement is to install rigid insulation around the exterior of the foundation. However, unless you are building a new house this is extremely expensive and usually not practical due to landscaping and driveways. Insulating around the interior of the foundation is your most practical option.

There are several key things to keep in mind when insulating a basement. First you want to make sure not to create any voids behind the insulation where condensation could build up. The best way to do this is to install rigid insulation or a rigid mineral wool sheathing board against an interior dampproofing layer applied to the concrete wall. You then build your stud wall directly again the rigid insulation. The second thing to keep in mind is using insulation products that don’t react with water. Insulating between the studs with a mineral wool batt insulation like Roxul is often best. Lastly is installing a vapour barrier. This is a bit of a point of contention in the building science world with some people insisting that it is not required but for now most building inspectors still want to see it installed to stop moisture migrating from the basement to the exterior.

Building a proper exterior basement wall should stop condensation that can build up inside of the insulation, in the wood framing and even pool on the floor behind the walls. That’s why poorly insulated basements create the perfect environment for mold and mildew. These bacteria are dangerous for your family to be exposed to and can lead to serious health problems. One of the most dangerous aspects about having a poorly insulated basement is that most people are unaware of the problem until it is too late.

For extra protection you can use a rigid foam insulation against the floors and strap around that insulation. There are also several propriety floor vapour barrier systems like Delta or System Platon that seal off the floor. As we outlined above, the proper type of insulation creates a barrier between the air inside of and outside of your home and can save you a lot of money and headaches when done properly.

Any questions about proper basement insulation and why it should be added to your basement renovation plan? Our experts can help, just contact us at 519-664-2245.