I need to install an exhaust vent and a window in my detached garage and the garage has asbestos siding on it. I am well aware of the dangers of disturbing asbestos but the bottom line is it has to be done and removing the siding is not an option at this time. Has anyone ever cut this type of siding before? I've drilled holes in it and it's pretty tough getting through and when I've tried to score some sample pieces and snap it, it didn't do well at all. I'm wondering if turning my circular saw blade around backwards or something like a Rotozip will work. Thanks in advance!

Pat

You should remove the shingle to work on it. It will break too easily if not supported close to the cut. You should be able to remove the nails. By gently prying close to the nails you should be able to pull then out enough to grasp with pliers and remove. They will be ring shank and will be a little hard to remove. If you use the claw of the hammer make sure that you do so with the head of the hammer against something solid behind the shingle or you will break the shingle. You could just cut the head of the nail off with a set of side cutting pliers. Cut hole with saber (jig) saw with support close to the cut.

I know that asbestosis is a hot topic but the folks who suffered from it where the miners who dug it up and people who worked in asbestis lined structures like a naval ship. We should no go around stirring it up unnecessarily but one cut is not going to kill you. You could play it safe and call a specialist in who can do an abatement or you could keep the siding under running water as you cut the hole. Your local building inspector should be consulted for additional advice, there may be code issues in your town and a permit may be required.

Ah, I hadn't thought about that! I could take down the ones I need to, cut them with a wet tile saw and put them back up. I can just draw my lines on them while they're in place and that will give me the exact cut lines I need and then put them back up like a jigsaw puzzle. The wet saw will help keep down the dust too. Excellent, thanks guys!

For vent or other holes in asbestos siding or where lead paint is likely to be can be drilled using a shielded hole cutter. Best shields are the ones from Hole Pro that make a complete air seal and to which you can attach a hose to a shop vac. For a hole cutter the minimum to get is a carbide tipped hole saw and best for lots of holes are the hole cutters with tungsten carbide teeth. The adjustable hole cutters from Hole Pro have tungsten carbide blades and I have cut 7" holes in asbestos and fiber cement board (Hardie,Certainteed, etc) using this hole cutter and a 18 volt cordless drill.