Manufactured home skirting: ventilation, moisture, and repair

Skirting does more than tidy up the gap between your manufactured home and the ground. It blocks pests and wind, but it must also be vented so the crawl space can breathe. A common rule of thumb is roughly one square inch of net free vent opening for every square foot of floor area, with vents spread evenly on all four sides.

Without cross-ventilation, humid air gets trapped under the home. That moisture condenses on the belly wrap, ductwork, and floor joists, which over time invites mold, rust on the steel frame, and soft spots in the subfloor. The goal of vented skirting is simple: let damp air out and dry air through.

How much ventilation, and where

• Aim for roughly one square inch of net free vent area per square foot of floor, or follow your installer and local code.
• Distribute vents on all four sides, with one within about three feet of each corner to clear dead-air pockets.
• If you lay a 6-mil polyethylene vapor barrier over most of the ground, required venting is often cut by about half.
• Keep vents clear: do not bury them behind landscaping, mulch, or stored items.

Spotting and fixing problems

Walk your skirting a couple of times a year. Look for cracked, faded, or blown-out panels, separated seams, and gaps where animals can get in, and after windy days check that panels are still seated in their top and bottom tracks. Inside the crawl space, watch for standing water, a musty smell, or sagging belly wrap, which all point to a moisture problem. Most vinyl panels slide out of their track for replacement, so a single damaged panel is an easy swap if you match the profile and color. For repeated damage or persistent moisture, many Valley owners upgrade to insulated or concrete-style skirting, which handles heat and impacts better and seals tighter against pests.