The greatest advantage of aluminum siding is that it is maintenance-free. In addition, it is non-corrosive and termite-proof, and will not rot. The siding surface is typically covered with a baked enamel-paint finish that can resist for many years before it fades, becomes dull and needs a coat of paint. If the siding is scratched, bare aluminum is exposed, however since it doesn’t corrode, the scratching only consists a cosmetic concern that can be easily corrected by touch-up paint.
On the other hand, one problem with aluminum siding is that it can be dented if struck hard enough. Moreover, many communities also require that aluminum siding be grounded electrically as a precaution against electrical shock.
Aluminum siding is available either with or without insulation backer boards. The insulation typically consists of a rigid foam such as polystyrene or fiberboard. The backer boards are only about ⅜-inch thick, but they are effective as an insulator for a house that has no insulation in the exterior walls. In addition, because of increasing energy costs even a house with insulation in the exterior walls will benefit from additional insulation.
The backer boards reduce heat loss during the winter months and heat gain during the summertime, and also increase the strength and rigidity of the siding. On the other hand, insulation-backed siding and tight siding jobs can cause moisture to accumulate within the exterior walls of houses that have no vapor barriers on the inside surface.
During an aluminum siding inspection, you can usually determine whether the siding has an insulation backer board simply by pressing on it. If the aluminum siding is relatively firm, it has a backer board, but if it yields and bends under the pressure it has no insulation board. Another method is to tap the aluminum siding. If no insulation is present it will make a hollow sound.
When performing an aluminum siding inspection, check for loose, missing and dented sections. Examine the exterior joints for open sections and weather tightness. In areas where electrical grounding is required, look for an electrical ground connection, a wire that runs from the siding to the inlet water pipe or a rod/pipe that has been driven into the ground. Check the local municipal building department to find out whether an electrical ground connection is required.