The most important factor in a successful wood flooring installation over radiant heat is a dry slab and a dry sub-floor. The only sure way to dry a slab and sub-floor system is to turn on the radiant heating system before installing the wood flooring. If this isn't done, moisture left in the slab will enter the wood flooring as soon as the heat is turned on. The result is floors that will expand, contract, shrink, crack, cup and bow excessively.
Opinions on the amount of time required vary widely. Some say the heating system should be turned on at least 72 hours before installation, with a preferred time of five to six days. That assumes that the slab has been in place for at least 60 days. If the slab is relatively new, the recommendation is to have the heating system turned on for 30 to 60 days before installing wood floors.
To be completely sure that the slab is dry enough you must always test for moisture content before installation and as always, follow the recommendations of your wood flooring manufacturer.
Proper drying of our wide plank flooring
Just as important as a dry slab and sub floor is the proper drying of the wood flooring you are about to install. When our products are being installed over radiant heat we kiln dry to 6% moisture content. Before installation we recommend no more than 2% difference between the slab and our flooring.
With radiant heat, the heat source is directly beneath the flooring, so it may gain moisture or dry out faster than a similar floor in a home with a conventional heating system. Wood flooring can be successfully installed over radiant heat as long as you understand radiant heat and how it can impact wood flooring, what precautions to take, and what type of wood flooring to use.