I’m working with a dry basement (generally) but I did notice a little mold on the back of some of the knotty pine and drywall I moved from the original “finished” space. The walls I took out had been built from the vinyl tile flooring straight up to the ceiling and attached to 2×2 furring strips that were bolted straight to the painted concrete walls. I want to improve the insulation of the basement and also the air circulation so that no mold will form in dead air cold spaces.
I don’t have the head space to raise the floor level up much above its existing spot (and I don’t want to re-configure my stairs) but I am laying down a new sub-floor system. I’m really pleased with the Dri-core sub floor system for this project.
This Canadian company makes these 2′ x 2′ tongue-in-groove panels that are a sandwich of textured plastic base bonded to an OSB top. They interlock together to form a strong, stable, level base for the new flooring and break the conducting effect of standing on bare concrete. The dimpled plastic on the bottom creates an air gap that allows any moist air or water to move through the space under the floor but is strong enough that I can build the new basement walls right on top of it (since they don’t carry any load). I set the new floor and furring walls away from the concrete basement walls (a 1″ air gap) so that air can circulate around the whole system.
I could have accomplished a similar result with rolled sheets of dimpled plastic and 4′ x 8′ sheets of OSB but I like d the modular nature of this system and the tongue in groove aspect.
Installing the system was fun and easy. I got to use the super fun new miter saw we just added to the family tool collection. Since it operates on a slide, it was able to cut more than half way through a panel so it was easy to chop, rotate 180 degrees and chop again. More complex cuts – like fitting the units in around the plumbing elements in the floor – took the jig saw.
Here is dad blocking the edge of the shower enclosure floor while I tap in some custom pieces around the shower drain opening. Can’t wait to start locking it down with the base plates for the new walls!