Crawl Space & Raised Floor Insulation in Biloxi, MS

Crawl space and raised floor insulation matters on the Coast because so many floors sit over open air or a vented crawl space. Homes raised on piers and pilings have the whole underside of the floor exposed to hot, humid outdoor air. Older houses on crawl spaces pull that same air in through foundation vents. Cool floors meeting warm, damp air means condensation, sagging batts, mold and musty smells.

Raised floors

For homes on piers, closed-cell spray foam on the underside of the subfloor seals and insulates in one step and stands up to humidity far better than batts held up with wire. It also seals the many penetrations for plumbing and wiring. ENERGY STAR suggests R-13 for floors in Zone 2.

Crawl spaces

For crawl spaces, there are two approaches. One is insulating the floor above and leaving the crawl space vented. The other is encapsulation: a heavy vapor barrier on the ground, sealed vents and insulated walls, turning the crawl space into a drier, semi-conditioned space. HomeGuide lists encapsulation at $3 to $10 per square foot, or $3,000 to $15,000.

Flood-prone areas

In low-lying areas, crawl spaces and raised floors may see water. Closed-cell foam handles occasional wetting better than other insulation. Check your flood zone and any local rules about enclosing space below the base flood elevation before planning work.

Termite inspection

Formosan termites are established on the Coast. We discuss inspection access around piers, sills and foundation walls before foaming.

Why batts fail under raised floors

Fiberglass batts under a raised floor are held up with wire or netting. In humid air they absorb moisture, sag, fall and give mice a place to nest. Closed-cell foam sticks to the subfloor, does not sag and seals the floor in one layer.

Plumbing and wiring

Raised floors have many penetrations for pipes, drains and wiring. Foam seals around all of them, which cuts drafts, humid air and insect paths.