Yes, I know, I have written about this topic before. However, since I see the condition so often, obviously my message is not sinking in.

This is a photo of the B-vent from a gas-fired water heater. The vent is passing through insulation in the attic. And that insulation is in direct contact with the hot metal B-vent.

No, No, No!. Wrong, Wrong, Wrong!

There should be one inch of clearance, minimum, between a B-vent and any flammable and that includes attic insulation. If the vent exits a garage ceiling, which often has zero insulation, this is not usually a problem. However, when the vent exits over the insulated part of the home, typically, a shield or a collar is put around the vent. That device keeps the insulation back and off the B-vent. With certain other vents anc chimneys -- oil furnaces and wood stove chimneys, significantly wider combustible clearances are required.

Thanks for stopping by,

Steven L. Smith