Mobile Home Siding Vents

[Rick Burkman]

These small vents are located in a low course of vinyl siding attached to a mobile home manufactured in 1996. The vents are on the north and south sides of the home, but not on the east/west sides (i.e., along the width, but not the length). The vents were not visible from within the crawlspace and no other ventilation was visible from inside the crawlspace. Crawlspace was made of a slab on grade and OSB walls with 2" x 4" treated lumber framing. Are these vents designed to create air flow or moisture escape from behind the siding? Or should they open into the crawlspace to provide limited cross ventilation?

[Robert Ernst]

The vents are at the front an back to encourage the most cross ventilation. They should be allowing air to travel under the insulation and above the plastic that is under the floor. Maybe that is why you couldn't see them.