How Do You Build a Roof Over a Mobile Home?

A roof can be added over an existing mobile home roof using traditional construction techniques. Materials needed for the project include lumber, insulation, nails, paint, sheathing material and shingles. To begin the process, a plate is nailed along each side of the mobile home, with nails going through the existing metal roof and into the tops of the walls underneath.

Caulk is used at nail points to keep water out of interior walls. Approximately 72 roof joists are cut, with an overhang of approximately 18 inches. Joists should be spaced at 24 inches to allow for standard fiberglass insulation. The slope of the new roof may be adjusted to match the slope of the existing mobile home roof. After insulation is in place, a vapor barrier is installed between channels in the rafters. Sheathing material is covered with roof felt and shingles to protect the new roof and make it look similar to other residential roofs. Overhangs may be covered underneath with particleboard. Vents, gutters and downspouts may be added at the time of construction or later.

Adding a residential-looking roof to a mobile home increases the home's value and decreases needed annual maintenance. It also conserves energy and reduces costs for heating and cooling. Some locations require a building permit to add a roof to a mobile home.