MH Belly Repair - Rigid Bottom Patching

Select sealants that:

are compatible with their intended surfaces,

allow for differential expansion and contraction between dissimilar materials,

meet the requirements of the applicable fire safety code (e.g. thermal or ignition barriers), and

for use inside the pressure boundary select low volatile organic compound (VOC) sealants that meet independent testing and verification protocols

Select materials that:

meet the requirements of the applicable fire safety code (e.g., thermal or ignition barriers),

create a continuous insulation layer when possible (i.e., rigid insulation board), and

rigid materials that adequately support applied load and are permanent air barriers

Remove any material from the sealing and patching area that will prevent full adhesion of the selected sealant and patch material

Patch any hole larger than 1 square foot with patch material that laps over the sub-framing on at least two edges

Install rigid patching material over all holes lapping a minimum of 3" over the surrounding material

Apply a continuous bead of sealant under the patch that creates an airtight seal

Attach patches using mechanical fasteners spaced no more than 6" apart

Use mechanical fasteners that incorporate washers/caps that prevent fasteners from being pulled through belly material

Install only noncombustible materials and sealants with an ASTM E136 listing in contact with any device producing 200 degrees F or more (chimneys, vents, flues, etc.)