Crawl Space Pandomonium

    Working in the crawl space beneath the floor is fun!  There are about 18 inches between the concrete ground cover and floor joists above.  In addition to the joists and insulation, there are water pipes, drain pipes, tubing for radiant heating loops, electric cables, wires for phone and computer jacks, fire sprinkler pipes and a fancy exhaust fan.
     The exhaust fan set up is clever.  According to code, a crawl space must either be vented to the outside or made an integral part of the building envelope.  Handicapped accessibility laws require that the main floor be no more than 2 inches above exit walks, which means venting to the outside is difficult.

Making the crawl space an integral part of the envelope means that it must be conditioned to control moisture.  This is usually done by installing an air conditioner.  Our solution was to install an exhaust fan to vent stale air up a pipe through the roof, while another vent in the far corner draws conditioned air down from the classroom above.  The fan is attached to an humidistat.  Thus, when moisture in the crawl space exceeds a certain amount, the fan turns on and the vent opens, keeping the space dry.  Bugs, cobwebs, mold and rot stay out!!!
    To tool around in the craw space we have a low-boy crawler.  The model crawler is Maddy P.