my house, let the nitpicking begin!

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Originally Posted by hearthman

Is your supply duct internally insulated to R-6? Also, I do not see any duct sealing.

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no, no insulation. this is a full basement/conditioned space.

no sealing duct is quite tight, but again... this is a conditioned space.

Conditioned space or not the SA plenum should be insulated to R-6/ R-8 in unconditioned spaces and the ducts should be sealed. The returns MUST be sealed per IRC for first 10ft. for combustion safety and new work should have a duct blaster test done. It also improves performance and is probably the single best thing you can do for any forced air system regardless whether a code officials *requires* it or not.

Hey, you asked for nit picking! BTW, rest looks very nicely done.

Quote:

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Originally Posted by hearthman

The returns MUST be sealed per IRC for first 10ft. for combustion safety

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Like a sealed combustion furnace is going to expel any products of combustion.

Quote:

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Originally Posted by hearthman

Conditioned space or not the SA plenum should be insulated to R-6/ R-8 in unconditioned spaces and the ducts should be sealed. The returns MUST be sealed per IRC for first 10ft. for combustion safety and new work should have a duct blaster test done. It also improves performance and is probably the single best thing you can do for any forced air system regardless whether a code officials *requires* it or not.

Hey, you asked for nit picking! BTW, rest looks very nicely done.

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i DID ask for nit picking, you're correct haha. thanks for the compliments.

interesting you bring all that up too. i agree that it definitely won't hurt my cause but i'm quite curious how much i would actually benefit from having my ducts sealed. beyond the fact that i have supply registers in the basement too.

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Originally Posted by JKopp

Like a sealed combustion furnace is going to expel any products of combustion.

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i agree with that, but i'd be more concerned with other things like my standing pilot water heater that's right next to the furnace. it's not like water heaters and other appliances are always right next to the furnace though either.

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Originally Posted by JKopp

Like a sealed combustion furnace is going to expel any products of combustion.

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Actually John, most "sealed" combustion units are NOT sealed. Leaky returns can and do pulled combustion gases out of CAT IV furnaces all the time.

The code is also addressing CAZ depressurization if there are other atmospherically vented appliances.

However, since ya'll seem to think this is BS, you can contact the IRC and tell them why they should rescind N1103.2.2, M1601.4.1, & M1602.2 for starters.

Then again, you always have *Best Practices* that call for sealed ducts to balance the system.

Quote:

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Originally Posted by hearthman

Actually John, most "sealed" combustion units are NOT sealed. Leaky returns can and do pulled combustion gases out of CAT IV furnaces all the time.

The code is also addressing CAZ depressurization if there are other atmospherically vented appliances.

However, since ya'll seem to think this is BS, you can contact the IRC and tell them why they should rescind N1103.2.2, M1601.4.1, & M1602.2 for starters.

Then again, you always have *Best Practices* that call for sealed ducts to balance the system.

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I agree, it would be great if we could seal all of them.

You could come ride with me for a year Hearthman, and I guarantee out of all the service calls we would do in a year we would see less than 10 systems with sealed and insulated ductwork and 9 of those would be attics or crawls. I am not disagreeing with you that it should be done.

I'm starting to see sealed ductwork on more and more new construction jobs but still not both sealed and insulated.

A draft interference test should be part of every tuneup where there are atmospheric burners to ensure sufficient combustion air.