What about moisture issues in my concrete?

Moisture is the number one enemy of epoxy adhesion. If moisture is migrating up through your concrete slab, it will push the epoxy coating off the surface from underneath, causing bubbling, peeling, and complete delamination. This is why professional moisture testing is a non-negotiable first step before any epoxy installation in Edmonton.

How We Test for Moisture

We use two industry-standard methods to assess moisture levels in your concrete before recommending any coating system:

• Calcium chloride test (ASTM F1869): A small dish of calcium chloride is sealed to the concrete surface for 72 hours. The weight gain tells us exactly how much moisture vapour is passing through the slab. Epoxy systems typically require readings below 3 to 5 pounds per 1,000 square feet over 24 hours, depending on the product.
• Relative humidity probe (ASTM F2170): Holes are drilled into the concrete and probes inserted to measure internal relative humidity at 40 percent slab depth. Readings above 75 percent RH indicate a moisture problem that needs to be addressed before coating.

A quick plastic sheet taped to the floor overnight can give you a rough idea at home. If you see condensation under the plastic the next morning, there is moisture movement that needs professional evaluation.

Why Edmonton Basements Are High Risk

Edmonton sits on clay-heavy soil that holds water like a sponge. Spring snowmelt and summer rain saturate the ground around foundations, and that water pressure pushes moisture through basement slabs. Older homes built before modern vapour barriers were standard are especially vulnerable. Even newer homes can develop moisture issues if drainage systems are compromised or if the water table is higher than expected.

Garage floors face similar challenges. Freeze-thaw cycles crack concrete over time, creating pathways for ground moisture to reach the surface. A floor that seems dry in January may show significant moisture transmission during spring thaw.

Solutions for High-Moisture Slabs

A failed moisture test does not necessarily mean you cannot have epoxy flooring. Several proven solutions exist:

• Moisture barrier primers: Products like Rust-Oleum Moisture Stop or Siloxa-Tek 8510 penetrate the concrete and create a chemical barrier that blocks moisture vapour transmission. These add cost but solve the problem permanently.
• Polyurea and polyaspartic systems: These coatings are more moisture-tolerant than traditional epoxy and can be applied successfully on slabs with moderate moisture readings.
• Drainage improvements: Sometimes the best solution is addressing the moisture source rather than just blocking it. Exterior waterproofing, weeping tile repair, or sump pump installation may be needed first.

We will never coat a floor that is going to fail. If moisture testing reveals a problem, we will explain your options honestly and recommend the right path forward. Request your free assessment to find out if your concrete is ready for epoxy.