Removing asbestos siding (fiber cement): Go over or remove?
Greenconfusion
| Posted in General Questions on
Removed one layer of Aluminum siding to discover Fiber cement siding ( possible asbestos). I wanted to remove to install Tyvek At wood clapboards. Is it ok to leave siding and old felt paper underneath and go over with foam board. I plan to use two inch of reclaimed foam and one layer of half inch new foam. Trying to do a sensible DER .
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Replies
Green Confusion,
Disturbing asbestos-containing products can cause the release of asbestos fibers. It's hard to assess the risks involved in the job you are describing.
One possible approach is to have a piece of the fiber-cement siding tested for asbestos. It's possible that the siding is asbestos-free.
It's also worth pointing out that asbestos regulations vary widely from state to state and even from city to city. If I were you, I would research the asbestos regulations that apply to your location before deciding how to proceed.
-- Martin Holladay
I agree with Martin's advice to test a sample as a first step. I also agree that you should find out and follow regulations.
Whether you remove or go over it, you'll want to make sure the work is done safely. For example, you might have workers assigned to put nails or screws through, which probably doesn't generate much dust, until they decide that a portion needs to be cut. You could easily have a situation in which your general contractor understands that issue, but the individual workers do not.
I agree , from a proper whole wall assy. can the the WRB go outside the foam with no condensation issues ? Also is it possible to use taped foam board with opposed seems and rain screen as a wrb ?
Trying to get a good idea of any pitfalls to leaving it attached as opposed to going over it with foam board. i do plan to cut new windows , so it will be disturbed. Also once aluminium siding was removed you can see outside around all bottom wall plates .
GreenConfusion,
Q. "Can the the WRB go outside the foam with no condensation issues?"
A. Here is a link to an article with the answer to your question: Where Does the Housewrap Go?
Q. "Is it possible to use taped foam board with opposed seems and rain screen as a WRB?"
A. Here is a link to an article with the answer to your question: Using Rigid Foam As a Water-Resistive Barrier.
--Martin Holladay
I'd test it. If it's asbestos, bite the bullet and have it removed properly. Otherwise, you may find your house is unsalable.
Sending to lab today in WV , $20.00 to $40.00 to test. Depending on layers . Thank you Martin for Articles.
An anecdote for others facing the asbestos issue... A friend lived in a house for years that had some textured application on the whole exterior. They wanted to paint and had a painter come out for an estimate who immediately declared it to be asbestos and quoted a fair, but very expensive remediation that my friends simply could not afford. So they lived with it. For years. Cracking, peeling, fading, worrying. Didn't look so good. Finally they saved up and decided it was time to have it done. They brought the sample to the lab, paid their $20 and found out...it wasn't asbestos at all.
Point being that you should always have these things tested not just to find out that it is something nasty, but just as often to find out you're in the clear. BTW, their house looks beautiful now with the new paint job and has gone from being a real dog to one of the nicest houses on the block.