As an energy auditor I occasionally see vermiculite in the gas fireplaces. Does anyone know if any of the vermiculite they use(d) for fireplaces has asbestos fibers and if it's safe to run blower door?
I put a drop on the fire place more for the soot and light fibers. You can get 3000 PPM CP very quick with open flame with rock wool or vermiculite what flame hits. I have vacked at whole room with a tear drop shape from the soot with open flame. That fire place pipe is just 1/2 black pipe sc 40 with holes drilled it then the gas runs though the rock wool and other fibers to make it look like "real". When I took at class on asbestos its listed as vemiculite as a holder.
when in doubt pressurize. That may not be a bad idea for fireplaces in general. I was suprised the first time I saw vermiculite in a fireplace. By pressurizing you won't pull any air past the fibers from the gaps around the damper making it safe even if yuou have asbestos contaminated vermiculite.
Eric, if I understood you opinion correctly you would not do a blower door test if there is any vermiculite in the house no matter what.
That brings me to an interesting question - what if the fireplace newer than 1978? I see newer houses, built in the 80s and 90s that that have fireplaces with vermiculite in them .
I would assume that any vermiculite in use since 1978 should have been tested safe.
Cory, I fully agree, pressurizing is always safer in case you have any sources of contamination.
It wasn't until about 1994 that it was discovered that there asbestos was found in the vermiculite in the Libby-Owen Mine in Montana, which was the source for 70% of the vermiculite sold in the US. Vermiculite is now considered a hazardous material, unless it has been installed since 1994 and the source can clearly be documented. Lots of information on this topic on the Web.
You are allowed to pressurize the blower door test, assuming that you will not be disturbing asbestos fibers that could enter the house. If vermiculite is in the walls and attic, there may be little opportunity for notable energy savings, and you would not be able to determine where the leaks are with a pressurized test, so why bother?
I have never seen vermiculite in or around a fireplace here in Vermont. Where are you finding this vermiculite in fireplaces?
If you go to a fireplace show floor like midwest fireplace or troost fireplace, they have 40+ working fireplaces mostly nat gas some wood some press wood with chains/dampers The very high end home will have a mix of rock wool and vermiculite that nat gas or lp gas will burn into, right on the 1 lb poly bag says vermiculite expanded and its an add on, replace each year, mix for look. I get 300 PPM CO off the flame and 100 +- in flue on low and high gets to 3000 PPM CO flame and 1000 PPM CO flue. I have seen the vermiculite turn black soot then white soot if burn is good. If you do not cover the soot/vermiculite/rock wool mix you will get a tear drop shape to the blower door. Its sold to make the fire places look kinda like wood burning.
Thank you very much for your reply, it was very helpful.
I've seen a number of fireplaces with vermiculite both in NY and Oregon.
Does anyone have any data on asbestos in the house from running a blower door? From the attic, basement or a fireplace?
I'd check with the local installers as to when the orig. install was and what product they were using. Grace, etc. stopped producing / selling ACM vermiculite in the mid. 90's.