Spray Foam Insulation Can Prevent Indoor Damp Walls This Summer | NFW Red Deer & Central Alberta Insulators

Summer might seem like the easiest season on your home, but the combination of heat, humidity and storms can create hidden risks that are expensive to fix later. At NFW Foam, we help homeowners stay ahead of those problems with one of the most effective upgrades available—spray foam insulation. It’s not just about keeping your home cool. Spray foam helps protect against a surprising number of seasonal issues that most people don’t think about until it’s too late – particularly, AC overuse and indoor summertime dampness. 

Is Your AC on All the Time? 

In the heat of summer, your air conditioner is already working hard. But if your home has unsealed gaps, poor insulation or inadequate attic coverage, your HVAC system will struggle to keep up. That means longer run times, higher power bills and an increased risk of breakdown. Spray foam insulation helps by sealing off the parts of your home that leak cool air, including attics, rim joists, basements and crawl spaces. By keeping cool air inside and hot air out, it lowers the demand on your AC system and can extend its lifespan. In Alberta, leak sealing is also a pretty big deal during the cold months, and spray foam insulation does a great job of keeping you cool in the summer and warm in the winter. 

What causes condensation / damp walls in summer? 

Condensation on walls during summer is usually caused by a mix of warm outdoor air and cool indoor surfaces. When hot, humid air from outside comes into contact with cooler wall materials—especially in air-conditioned homes or buildings—it creates moisture. This is especially common in basements or poorly insulated spaces where walls don't have a proper thermal barrier. Without insulation to regulate interior surface temperatures and reduce humidity movement, water vapour in the air turns to liquid on the walls, leading to dampness and potential mould growth. 

How to stop damp in a summer house? 

To stop dampness in a summer house, the most effective solution is to reduce humidity while improving the building envelope. This means sealing cracks, controlling airflow and installing insulation—preferably spray foam—to prevent warm air from bringing moisture inside. You’ll also want to ensure the space is well-ventilated to allow air to circulate and moisture to escape. Dehumidifiers can help short term, but long-term damp control depends on creating an airtight, well-insulated shell that resists temperature swings and moisture intrusion. 

How do you fix high moisture in walls? 

Fixing high moisture in walls starts with identifying the source—whether it's poor ventilation, air leaks or external water entry. Once the cause is found, the next step is to dry out the affected area and prevent the issue from recurring. In many cases, installing closed-cell spray foam insulation can stop moisture movement by creating a vapour-resistant barrier. If the wall is absorbing moisture due to poor insulation or air gaps, sealing it with spray foam will not only address the immediate problem but also improve energy efficiency and air quality. 

How do you fix dampness in walls? 

Damp walls require both treatment and prevention. After drying the wall and removing any visible mould or mildew, the root cause must be addressed—often related to poor insulation, thermal bridging or water ingress. Spray foam insulation is one of the most effective ways to fix this because it blocks airflow, resists water and eliminates the cold surfaces that attract condensation. For long-term results, it’s important to insulate from the inside out, sealing off the gaps that allow moisture to build up in the first place. 

Condensation in Metal Structures 

If you have a workshop, pole barn, detached garage or metal building, you’ve likely seen condensation forming on the inside during summer. That moisture can corrode fasteners, rust framing and damage stored equipment. Spray foam adheres directly to metal and acts as both a thermal and vapour barrier. Once installed, it helps regulate the surface temperature of your building so condensation doesn’t form. This makes it a smart long-term solution for protecting tools, vehicles and the structure itself. 

At NFW Foam, we help homeowners stay ahead of summer problems with smart, long-lasting solutions designed to perform for years to come. Get in touch for a free spray foam insulation project quote or to talk about attic insulation, soundproofing, or vapour blasting in Red Deer and area.