View Full Version : Opening through flues

Jon Randolph
04-07-2008, 05:32 PM
This was a home that I inspected Saturday.

The (now unused) flue for the basement furnace was open through to the flue for the wood fireplace. The furnace flue was lined with a class B vent and was sealed off at the basement but open at the top of the chimney.
I listed it as a safety hazard that a certified chimney sweep evaluate and give direction to the required repair. Realtor was present and did not see how it would be a safety hazard. (I know, I know)

I do feel that it is a safety hazard, but would like to hear others feedback (especially from Bob)

Sorry about the dark picture.

Bob Harper
04-07-2008, 06:12 PM
Each flue must be separated by one brick wythe min. Wood cannot share with other appliances. B-vent would have to be listed for use inside a chimney and installed to the listing, which would include the termination and how to seal off the top of the flue as well as support it. Many mfrs. won't allow B-vent inside a chimney because there is no way to inspect it. Identify the B-vent mfr, get their listed instructions to see. Other details such as smoke chamber wall thickness & parging, etc. lots to choose from.


Jon Randolph
04-07-2008, 07:05 PM
The b vent was no longer in use as they now have a high efficiency venting out the basement wall with PVC, so I didn't get real excited about it's presence.

And they were actually 2 separate flues, only they had that 3' opening between them. (which would allow the fireplace to use both flues)

This is the same home as the flue height post that you replied to.

Thanks for your quick reply.