"A contractor can install a plastic, vinyl shield on the existing joist and remove the ground cover. Also, closing the venting system in the winter and opening it in the summer helps."
Home inspector/engineer Harry Gross in Cherry Hill reminded me that we once talked about sealing off the crawl-space vents with vapor barrier and insulated walls as the best approach for this region.
But when there is a lot of moisture, as there may be 200 yards from the bay, there are two approaches to dealing with it, Gross said.
One is to channel any water that may enter the crawl space, preferably lined with a concrete vapor barrier, into a sump with pump for removal.
The other is to not have a vapor barrier (this allows water that enters to drain out through the porous sand), insulate the floors with a vapor barrier on the insulation and keep the crawl space well-vented to carry or dry out the moisture within the crawl space.
"So, basically, it is to choose how to minimize the moisture in the crawl and then properly deal with any moisture that makes it in," Gross said.
Thanks to both of you for your help.
Sump pumps. Tri-County Inspection president Jack H. Milne Jr. sent along a story about a client in Glassboro who had a sump pump with a backup battery that wasn't working when he tried it.
I'm relating this because he offered an explanation of the water-powered backup system we've been talking about since Irene hit us over the head in late August.
The system "uses water power to create a Venturi effect, a technology that's been in use for almost two centuries for many processes," said Milne, based in Morrisville, Bucks County.
