After we have installed the beams, we attach a continuous layer of vapor barrier film under the beams. Many builders attach the vapor barrier on top of the beams. Sometimes they use this as an argument that the beams should dry out, but this is wrong.
The beams should initially be dry and do not need to be dried out. In the wrong case, there will be a cold bridge between the beams and the vapor barrier, and as a result, you will have a cold floor in places. From below, we hem the floors with a board or use a cord to fix the insulation.
Next, we lay the insulation in several layers between the beams. It is imperative to lay the insulation with an overlap of the joints, again to avoid cold bridges. At the next stage, we lay a layer of vapor barrier on top of the beams and insulation. And be sure to glue it with an overlap.