Expert: James Ball - 10/13/2008

Question
For the last two years we have had many wasps coming down our chimney.  
We have a prefabricated fireplace unit with a gas insert and gas logs.  When
we open the flu wasps will fall down into the fireplace as well as fly out.  We
killed 18 wasps today with our trusty butterfly nets!  They seem to come
around October.  Pest control people were out last year and did not find any
nest, flu was clear.  They wouldn't spray in the fireplace area.  Can we safely
use a barrier of wadded up fine metal mesh screening shoved up into the flu
past the damper to keep the wasps from coming in?  We never burn wood.  
We have burned the fire for many hours thinking they would go away, but
they are always there the next time we open the damper.  We cannot safely
reach the chimney cap which has a screen but the holes are large.  A barrier
of mesh seems to be the only answer we can come up with and I want to
make sure it would be safe.

Answer
Hello Jodi, you can plug the flue with what every you want but you can not use the fireplace with it in there. they may be attracted to the gas smell?
I would have a local Certified Chimney Sweep (www.csia.org, there you can look up by zip code to find one near you) take a first hand look at what you have. if you kill the nest they should not come back.
hope this helped
James Ball