Venting of Heater and Water heater

Should the ducts connections be taped or is
overlapping ok ? I observed sheet metal duct overlapping with
a abestos like duct leading to the roof for the heater. Is that ok
or should some type of tape be added. The house is aprx 40 years old
Southern Calif.

New home inspector

I assume (based on the thread title) that you are referring to the vent system rather than the distribution system. If so. . . .

A natural draft vent system does not necessarily need to be sealed, but you should recommend removal of the Transite (assuming again) portion of the vent. This would be the asbestos type vent you referred to, which are very common here in SoCal.

Thanks for the info

Hi David,

Are you referring to the joint at which the flue piping is connected or
a coating on the flue?

The slip fit of most flue piping (different types for different applications) should follow a pattern. Starting from the appliance the fit should be inserted “into” the next segment not “over” the next segment downstream. Following the flow pattern of the exhaust ( combustion gases) ---->>----> Not ----<>----> (these are the ends of the flue piping > into >) .

Just in general , MFG installation instructions are the number one
recommendations to follow.
You can find these in the booklets that “should” be next to any Natural gas burning appliance. If this booklet is not there then the home owner should have it in their possession .

For a great explanation of Natural Gas burning appliances (flue function) see

Goto “Venting Done Right” and watch the video. :wink: