I talked to a builder yesterday about this direct vent for a 20,000 BTU nat. gas fireplace. The vent is stamped keep clear 2ft. The builder said it is not a problem and he has other houses with this install. My concern was the wood member directly above the vent. I thought it could be flashed on the top side. What is your opinions? Thanks.
If you know the manufacture, go find the installation instructions / procedures (almost always online at the website), and if it backs up your concerns (download for future reference), refer to them when you voice your concerns and move on. If the customer still wants to buy the home you have done your job and there is little else you can do. It will not pay off in the long run for you to get into a pissing match with the builder (that is the buyer’s job). Make sure you know what you are talking about before you do anything though. Back it up with documentation. State the facts, let the facts speak for themselves, keep your emotions out of it. Remember, you are the “disinterested” third party.
If it were me I would obtain the manufacturer’s installation manual to determine proper clearances. For instance, Lennox direct vent installations allow 2.5" projections of combustible material within 3" of the vent. Anything over 2.5" must be 24" away.
See fig 5 but again this is for a Lennox product only:
Lennox fp.pdf (192 KB)