This occurs from water that either leaks under the subfloor or from moisture within the concrete slab itself.
Ideal moisture sub floor house.
A concrete slab makes for a very hard solid durable and often very smooth subfloor.
When that occurs dirt and dust or other debris under the subfloor could become a substrate for mould growth.
A week ago it was down to 12 or 14 depending where you checked.
It may be made of boards laid either at right angles or diagonally across joists.
The ideal humidity for the home is around 40 to 50 percent which is high enough to prevent things from drying out but low enough to prevent damage and mold growth.
Hardwood floors the maximum subfloor moisture level will be either 12 or 13 depending upon the manufacturer.
High humidity in the home can cause serious problems with your flooring.
Two weeks ago the moisture in the subfloor was 22.
In this chart you can see a small highlighted section.
With the addition of decks and increased vegetation from gardens and shrubs the natural cross flow ventilation under homes can be negatively impacted and the usual humidity released from the ground therefore cannot escape the sub floor space.
At this equilibrium moisture content emc wood will stop absorbing or shedding moisture which prevents some of the physical problems that can occur in wood flooring.
I m using a pin tester and checking at a depth of 1 8 to 1 4.
For all intents and purposes the ideal moisture of flooring wood will be the moisture content at which the wood reaches equilibrium with the installation environment.
Subflooring provides a base for finish flooring and also serves as a platform during construction.
Humidity is the amount of water vapor in the air.
Moisture is constantly released into the atmosphere from the earth and is dispersed by the wind.
The efflorescence you are seeing when you lift the individual subfloor tiles is caused by minerals leaching from the concrete.
This chart highlights the ideal levels of moisture in wood at various temperatures and relative humidity rh levels.
Then the hardwood flooring moisture content must be within 2 4 of the subfloor moisture.
Today it was at 12 or 14 still.
These are the safest conditions for most types of wood between 60 and 80 degrees fahrenheit and 30 to 50 rh.
Or the subfloor may be made of plywood or other panel products that are laid perpendicular to the joists.
2 for plank 3 wide or more hardwood and 4 for strip 2 wide hardwood.
Tile and stone flooring can be installed directly over concrete but most other flooring materials require some kind of underlayment and or a moisture barrier laid over the concrete.
While it s important to extract moisture and treat the top level of your wood floors it s all for naught if you don t do the same for the sub floor.