I insulated the crawl space walls and bonds with Polyurethane spray foam 3 inches thick.
The heating ducts run through the crawl space and are not insulated.
I have an open heat vent in the crawl space area.
The cold air returns are in the attic and they are insulated
I did not install any outside vents, figuring this would be a "conditioned" crawl space.
I am still finishing inside the house and no insulation is on the walls of the house yet
I heat the house only on weekends while working inside.
I have 3 inches of pea gravel over a dirt/clay ground
I have not yet covered the pea gravel with 6 mil plastic, but plan too.
I've noticed condensation on PVC drain pipes and on the underside of the flooring between joists starting just inside the insulated bond area. It has only been about a 1-1/2 months and already I am seeing some mold/mildew forming on the underside of the flooring between the joists.
I am concerned with the mold/mildew forming so quickly, so I was considering spraying the flooring between the joists (using a garden sprayer) with bleach or TSP to eradicate the freshly formed mold/mildew. I would do this before covering the pea gravel over with a 6 mil plastic vapor barrier. Once that was done, I was going to seal up the entry.
Am I doing all that I can or should do, or do I need to do something more or differently? Any suggestions would be appreciated. Do I need to put a humidifier down in the crawl space for a short period of time to dry it out after spraying or just cover it with the vapor barrier and let gravity deal with the problem? Is the spraying of bleach of TSP recommended or an overkill on my part?