Single Wall Duct Clearance

Old 05-29-16, 09:18 PM
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Single Wall Duct Clearance

I'm building a wall in my basement that I think won't quite meet code for clearance between a single wall gas exhaust and combustible. At the closest, the pipe is 4.5" from the wall. Picture shown below!

I think I can get this to meet code, by installing a "Heat Shield".

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Two Questions... (Edit Three)
Can anyone provide me a link to appropriate code for this process?

Are the heat shields made by bending a piece of sheet metal? I can't seem to find one at my local building supply.

The ol' man is trying to tell me I can put fiberglass insulation around the pipe to keep the heat in. Thoughts?

Pictures of pipes

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Tags: Vent Clearance Furnace hot water heater single wall pipe 6" inches 1"
Old 06-11-16, 10:51 PM
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I would refer to the furnace manual for the correct venting requirements.

I would be surprised if single wall vent pipe is spec'd.
Old 06-12-16, 01:06 PM
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If the furnace has an inducer motor, it's an 80% efficient furnace and should have double wall vent pipe to prevent combustion gases from condensing in the vent pipe.

If it's an older furnace that has a draft diverter, single wall vent pipe is OK.

Clearance to combustibles with single wall pipe is 6".

I don't know about how a heat shield affects that. You'd have to do more research than I can provide.

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