Gaskets are used to seal joints where caulking may not be appropriate. Table 3-3 describes the most common types of gasket materials and where each type works best.
installed between the foundation and sill plate during construction or where existing house walls meet
staple to hold it temporarily in place
cuts easily with a knife
available in 152 and 203 mm (6 and 8 in.) widths on 24 m (79 ft.) rolls
Foam backer rod (closed-cell compressible foam rope)
excellent for filling gaps before caulking
ensure caulking will fill the gap (see product specifications for maximum joint width)
available in diameters of 6 to 50 mm (1/4 to 2 in.)
Electrical outlet and lighting fixture gaskets (pre-cut)
designed to fit behind the cover plates of electrical receptacles, switches and lighting mounts
electrical outlet gaskets are more effective when caulked and should be used in conjunction with child-safety plugs to reduce air leakage through electrical sockets
place the centre cut-out piece of foam gasket over the end of the electrical plug or child safety plug to ensure a proper seal
Neoprene and elastomeric gaskets
excellent for sealing joints and penetrations where movement is to be expected such as plumbing stacks
best slipped over piping, if possible
very difficult to seal if it must be cut to fit around piping
