Before they re-insulate the underside of a manufactured home, general contractors take some precautions to ensure they perform work properly. Beneath the home, the ducts should be fully sealed, as should the utility pipes and floor joists.
In an older dwelling, work may begin with checking ducts for leakage. If the utility connections underneath the manufactured home leak, a general contractor can assist you. Generally, they will open up the belly wrap and put an R-14 batten strip sealant over 2 inches foam board. Contractors tend to use the fiberglass batten strips under the floor joists, but not on water lines. This is mainly because they do not hold water. Nonetheless, fiberglass batten strip sealants are used beneath single wide mobile homes, as they are current sealants in manufactured housing.
Methods Used to Insulate Manufactured Home Undersides
There are two methods to insulate the underside of a manufactured home – “belly blow,” and “side blow”. In the belly blow method, general contractors drive holes through the belly fabric to fill the joist cavity. If the joists run crosswise, a contractor may cut a hole in each joist bay and blow apart torn insulation. However, if they run lengthwise, the contractor may make wider holes in each joist bay to fill the floor with batten strips.
Blowing from the underside is a tough ask for a general contractor and hence side blow method is chosen to insulate floor joists. In the side blow method, general contractors employee lifts the siding at the edge of the framed floor, drills the joist rim, to blow torn batten strips from the sides with a hose.
The access is one of the main concerns for a general contractor hence crawlspace underneath helps implement perfect methods to insulate the underside. If the joists were running lengthwise or even crosswise, a crawlspace of, say, thirty feet or more would help. Note that the personal belongings and such shall be removed from the floor before presuming the work as a precaution, and to access floor joist cavity from beneath with a flashlight. Remember, it is the underside of your home, and there may be imperfect light and other imperfections such as leakage on unsealed or improperly sealed homes.