Comment identifier et résoudre les problèmes d'humidité dans votre sous-plancher en béton

Vous avez fait tout ce que vous pouviez imaginer pour préparer votre parquet en vue de son installation.

Vous avez vérifié les niveaux d’humidité.

You let it acclimate to the environment.

So why is your client calling you about moisture damage?

The problem might run deeper than you think. Perfectly acclimated wood flooring can still be damaged if it’s exposed to moisture later on. That can come from things like leaky pipes or windows. But one of the sneakiest culprits is deeper within your floor: your concrete subfloor.

Concrete subfloors can release moisture, which is then absorbed by the flooring above. If the concrete subfloor contains high moisture levels, your floors may swell, buckle, cup, or discolor.

Heureusement, il existe un moyen d'éviter ces dommages. Voici les mesures que vous pouvez prendre pour protéger vos sols, notamment :

• Comment identifier les niveaux d’humidité élevés
• Comment corriger les niveaux d’humidité élevés
• Ce que signifie pour vous garantir la qualité du sol

Comment identifier les niveaux d’humidité élevés

Avant l’installation, vous devez vérifier le sous-plancher.

Some moisture problems in subfloors are obvious, such as sweating, dampness, or mold. Or you might notice efflorescence, a white, powdery residue that shows up when moisture carries the concrete’s salts to its surface.

Unfortunately, high moisture levels in concrete often go unnoticed. A concrete subfloor can appear dry when it isn’t, with excess moisture still beneath the surface.

So the only way to truly know a subfloor’s moisture condition is with the right tools and procedures.

Commençons par la première étape.

1. Vérifiez l'étalonnage et préparez la zone

First, make sure all your in-situ relative humidity (RH) sensors are calibrated as ASTM F2170 requires, and keep documentation of that calibration.

Next, ASTM F2170 requires the area you’re testing to be at service conditions for 48 hours before you begin testing.

2. Prenez des mesures d'humidité

Pour ASTM F2170, installer trois Capteurs d'humidité relative rapides for the first 1,000 square feet of your floor. After that, install one sensor for each additional 1,000 square feet.

Want to find the best spots to place your sensors?

You can use a concrete moisture meter, like our C555 Concrete Moisture Meter, which reads 0.5 inches into the slab. These meters can show which areas of the slab have the highest moisture levels near the surface compared with the rest of the subfloor.

That makes them a great companion to RH testing. Some flooring professionals choose to use a concrete moisture meter as the final say on whether their concrete is dry enough for a floor covering.

If you do use a concrete meter by itself, choose an accurate one, like the C555. That will help you make better judgments about the concrete’s moisture levels.

However, keep in mind that using a concrete moisture meter as the final say on whether concrete is ready for a floor covering doesn’t comply with ASTM F2170.

So let’s go back to how meters work together with RH testing.

When you identify moisture hot spots with a concrete moisture meter, you can place your RH sensors in the areas with the most moisture. That way, when those areas reach the appropriate moisture level, you can be more confident that the rest of the slab has too.

However you choose to place your sensors, ASTM F2170 requires you to drill the holes to a specific depth: 40% of the slab’s thickness if the concrete is drying from one side, or 20% if it’s drying from two sides.

Place your sensors in the drilled holes and wait 24 hours before taking the ASTM F2170 reading.

You’ll still need to wait that long to meet the standard, but Rapid RH sensors can give you an early indication of the concrete’s RH within the first hour. That preview can give you extra time to plan how you’ll deal with any moisture-related problems.

3. Évaluer les résultats d'humidité

So now that you have your readings, how do you know if they’re too high?

ASTM F2170 tells you how to measure RH, but it doesn’t set a pass/fail limit. That number comes from the flooring manufacturer. A commonly specified limit is 75% RH, but always follow the manufacturer’s specification. If your readings are higher than the manufacturer allows, let the concrete keep drying before you install the floor covering.

You can usually find this information on the flooring manufacturer’s website or in its installation instructions.

Comment corriger les niveaux d’humidité élevés

If you identify high moisture levels in the concrete subfloor, here are some steps you can take:

1. Arrêtez l'humidité avant qu'elle n'atteigne votre revêtement de sol

Before doing anything else, check for any sources of moisture intrusion.

If there aren’t any, the high moisture levels may be from water left over from when the concrete was first mixed and poured.

But if a leaky window or pipe caused the subfloor’s high moisture levels, it needs to be repaired to prevent future moisture intrusion.

2. Séchez le sous-plancher

Next, dry the subfloor to lower the concrete’s moisture levels. Use fans to improve airflow, and adjust the room temperature as needed. Dehumidifiers will help pull excess moisture out of the air.

Some slabs, especially older slabs where moisture vapor retarders were never installed, may never fully dry out. In that case, the only option may be installing a moisture mitigation system over the concrete.

3. Surveillez les niveaux d'humidité

Keep an eye on your RH readings while you wait for the subfloor to dry.

You can streamline this with our Système de surveillance à distance True Remote Monitoring™, which lets you view RH readings anytime, anywhere, without traveling to the job site. You’ll know when your subfloor has reached the right moisture level to start the floor installation.

Ce que signifie pour vous garantir la qualité du sol

Making sure your concrete subfloor is at the right moisture level before you install floor coverings can help you avoid a lot of headaches down the road.

For one, you won’t have to worry about moisture damaging the floor covering. You also won’t have to worry about letting your clients down.

Checking the concrete subfloor can help you build a reputation as a careful, thorough flooring installer who does what it takes to provide high-quality floors.

And it all begins with accurate moisture testing, using tools like our C555 Concrete Moisture Meter and Rapid RH in-situ sensors.

Acheter Rapid RH

Dernière mise à jour le 14 octobre 2026