Moisture Control

Concrete Moisture Control & Mitigation

All concrete contains water, but too much can cause problems, including total failure. Concrete Fusion can control and mitigate the moisture in your concrete, ensuring it lasts as long as possible without issues.

Moisture Vapour Transmission, What Is It?

Moisture Vapour Transmission(MVT) is a natural process where water evaporates out of concrete. Even in older concrete slabs, MVT occurs if water comes into contact with them due to failed moisture barriers or other issues.

MVT is critical in concrete flooring because if there’s too much moisture in a slab, it can quickly damage or ruin any product on top of it. Moisture testing can tell us when a slab is ready for flooring or if we need to use a moisture tolerant flooring type.

We Mitigate Moisture Issues

Moisture mitigation systems minimize the impact of moisture on flooring and reduce the risks of moisture-related issues. While they come with upfront costs, they prevent expensive and time-consuming problems in the future.

The goal of any moisture mitigation system is to limit or prevent the movement of water vapour into the flooring system. This vapour could come from external sources, like groundwater, or internal sources, such as moisture evaporating from an insufficiently dried concrete slab. 

Regardless of the source, moisture naturally moves from areas of high concentration to low concentration until equilibrium is reached. Disrupting this process is crucial for avoiding moisture-related complications.

An effective moisture mitigation system may include several components, such as:

Vapour Retarders

Vapour retarders or vapour-retarding membranes provide a pre-formed barrier between a subgrade and a poured concrete slab. In some cases, they are installed above the slab for specific flooring types, such as under wood or laminate flooring. These retarders have different “perm ratings” that indicate their permeability levels. Some also block gases from moving along with water vapour.

Surface Membranes/Applied Barriers

This category includes epoxy primers, sealers, and sheet membranes applied directly to a concrete slab or subfloor to reduce permeability between subfloors and the final flooring material. Other options include acrylic latex resins or cementitious layers that create a non-permeable barrier to prevent moisture migration. We generally use products recommended by the flooring manufacturer to ensure proper installation and performance.

Adhesives

There are many flooring adhesives available that manufacturers claim can withstand higher moisture levels. Using these specialized adhesives can sometimes be a proactive solution to moisture issues.

The success of any mitigation product or adhesive depends heavily on proper installation techniques. Always follow the manufacturer’s guidelines.

Moisture Testing 

Accurate measurement of moisture levels or relative humidity (RH) in the subfloor is crucial before and during flooring installation.

For concrete subfloors, RH testing is the most reliable indicator of the moisture content, helping to determine when the subfloor is ready for flooring installation and the appropriate product selection. Factors such as the initial concrete mix and job site conditions influence the RH levels, and only RH testing can provide accurate information.

Failure to measure and plan for potential moisture issues can lead to future flooring problems. However, with proper planning, use of moisture measurement tools, and the right moisture mitigation system or moisture-resistant adhesives, the flooring can achieve a long-lasting lifespan.

Your Moisture Control Experts

Concrete Fusion is a highly experienced team for controlling and mitigating moisture.