Asbestos shingles are relatively strong but.
Asbestos in aluminum siding.
Covering old asbestos shingles with new siding may seem like an option too but it s not easy to do safely.
Asbestos siding is composed of asbestos fibers mixed with portland cement.
Cement asbestos wall shingles outside and not easily friable unless being demolished or cut with power tools.
Asbestos ranks high on the list of dangerous substances because of its toxic and carcinogenic properties when airborne.
If you suspect that your siding may contain asbestos there is no need for alarm.
Efflorescence chalking can commonly be seen on asbestos siding.
Let the siding dry then prime and paint with the best exterior latex you can find.
See photos at asbestos siding in this document.
The siding may also contain asbestos if it is old with a wood grain texture to resemble cedar.
If your siding fits either of these descriptions you should consider having it tested.
Testing your siding for asbestos.
These shingles are generally 12 by 24 inches and the bottom tends to have a wave like pattern though that is not always the case.
Aluminum siding is pretty easy to identify.
It is very brittle and has a tendency to crack and break when nailed which can release asbestos fibers into both the air and ground.
Because fiber cement siding manufactured in north america after around 1978 was made without using asbestos in those later products and because those non asbestos fiber cement shingles included products that by eye were an exact visual match for their older asbestos containing brothers and sisters already installed a building built.
If a siding company removes an outer layer of siding and finds an older layer of asbestos cement siding beneath the standard procedure is simply to cover it over with new siding rather.
If your house was built around or prior to the late 70 s has the original siding and seems to be made of cement it is probably asbestos siding.
Alternatively if you leave the asbestos on your home you can safely seal the old siding underneath the new siding and because asbestos is an excellent insulator you will actually be adding to the energy efficiency of your home by leaving it on.
Lead paint wasn t outlawed until 1978 so it s sure to be present on siding going back to the 1950s.
Removing asbestos is often cost prohibitive for most people.