Why Test For Moisture Content Of Slab Before Laying Hardwoods

For woodworkers who build cabinets fine furniture musical instruments dishes toys decorative art boat restoration or various other wood products the acceptable wood moisture content normally ranges from 6 to 8.

Why test for moisture content of slab before laying hardwoods.

Before moisture testing begins the concrete slab must be a minimum of 30 days old. If your subfloor is above 12 moisture dry out the subfloor before installing hardwood floors. With summer quickly approaching rising humidity levels can compromise your wood floor installations if not accounted for. Therefore it s advisable to have a floor tested for moisture content prior to installing flooring or moisture barriers.

You must test the concrete slab for excessive moisture. Determining moisture content of both the wood flooring and the subfloor is an important part of quality control in the flooring installation process. Testing concrete for moisture astm f2170 stipulates the use of in situ probes to determine the moisture condition of a concrete slab at the time that it will be sealed or covered by flooring material. You can combine them to get the best read of your moisture conditions.

The hardwood flooring s moisture content mc should be in balance with its surrounding ambient environment to support the. Test for dryness new concrete is heavy with moisture and it must be a minimum of 30 days old before moisture testing begins. How to do a moisture test for concrete slabs. How to check moisture content in concrete floors.

Moisture levels can be read with a meter like the wagner mmc 220 this is a pinless meter and allows you to get an accurate reading without sticking pins into the floor and creating pinholes. Flooring specialists can test the moisture content of a wood subfloor using the pinless wood. Moisture on the inside of the plastic in the form of dampness or even fogginess indicates the slab is expelling moisture in measurable amounts. The normal moisture content of wood or emc varies from 7 19 depending on the rh in the air.

But before you begin it s important to understand that moisture measurement and management is crucial to both the concrete slab and also the hardwood flooring. Slabs less than 60 days old are generally too wet to install floors. The american society for testing materials astm has several standard tests for measuring moisture levels in a concrete slab. Concrete slabs wood subfloors and the wood flooring placed above a slab or subfloor are by their very nature porous.

Concrete slabs and floors can be excellent subfloor surfaces for tile and other floor coverings but too much moisture in the concrete can cause problems with flooring installations. Let s look at how moisture affects concrete before moving on to moisture s effect on wood flooring.