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John Stephenson
06-19-2007, 10:29 AM
..........

Bob Harper
06-19-2007, 06:25 PM
Forget the cable--this is a fire hazard! Chase not enclosed, insulation in direct contact.....

Jerry Peck
06-19-2007, 07:37 PM
Bob,

Nothing about the foil type fresh air duct? I thought that was not allowed.

I agree - little else is correct, the NM cable is the least of the problems.

Dale W. Feb
06-20-2007, 10:28 PM
John,
Non metallic, electrical is allowed within these chase areas. There are however a common problem for clearance and contact. As long as they are properly secured, and provided the listed clearance of the hearth components, they are allowed. Now if this were a return air plenum, then a smoke-rated NM wiring would be required.

The insulation surrounding the chimney is a common fire cause. These system ALL require an “AIR SPACE” clearance. This air space allows the heated air to mix with cooler air. When we capture this heated air beneath the insulation, temperatures increase and the heat migrates horizontally to a fuel source (the wood framing).

Fuel for thought,

James Duffin
06-21-2007, 05:14 AM
Does anyone know of any prefab fireplaces that the manufacture instructions says you don't need a hearth? I ran across a installation the other day on a warranty inspection that I questioned and the owner said the builder had done several houses in the neighborhood with no hearth. Just a wood floor. I told him that it was not up to any code I know of and thy he should ask the builder to show him some documentation that states it is ok to have no hearth. If he can not then a hearth needs to be installed per code.

Scott Patterson
06-21-2007, 05:51 AM
Does anyone know of any prefab fireplaces that the manufacture instructions says you don't need a hearth? I ran across a installation the other day on a warranty inspection that I questioned and the owner said the builder had done several houses in the neighborhood with no hearth. Just a wood floor. I told him that it was not up to any code I know of and thy he should ask the builder to show him some documentation that states it is ok to have no hearth. If he can not then a hearth needs to be installed per code.

Yes, they are available. You will need to get the manufacturer and model number and then you look it up on the manufacturers website. Or if the installation manual is around it should be in it as well.

The one in the picture does not look like one, but don't go by my word on that. The ones that I have seen have been raised up higher than what you have in the picture.

Thom Walker
06-21-2007, 05:54 AM
Forget the manufaturer specs and the old codes. This does not need a proper hearth extension. Not according to the IAC (International Arsonists Code).:D

It may have a hearth. It just happens to be a combustible hearth extension. Deal Killer. Look at sections R1001.9 through R1001.10 in the IRC. R1001.9.2 will have a cut and paste for you to give your client.

Richard Stanley
06-21-2007, 06:14 AM
The pic looks like one of those electrical units - not a real fireplace - just a glorified light bulb.

Bob Harper
06-21-2007, 06:47 AM
regarding the air kit ducts, most mfrs. simply call for a Class1 duct, which means a flame spread of 25 or less. A lot of AHJs will allow the flex slinkies but require rigid as it penetrates a fireblock.

The floor protection is a function of the testing. The ANSI Z21.88 std for vented room heaters allows floor temps. up to 117F above the ambient room temp. This is based upon test room conditions but as far as you guys are concerned, if the listed instructions don't require floor protection, then it doesn't--period. Also, I've seen plenty of thick stone slabs that block the cooling air entering that lower compartment, so that's a case where a hearth can be a detriment. Yes, there are some gas fireplaces that do require a non-combustible hearth extension. Typically, these are high BTU input radiant heaters with no convection chamber. Take for example the Heat&Glo Escape. When installed flat on the floor, it requires a non-comb. protection 12"x36". If it is mounted 4" off the floor, it does not require any floor protection.

With manufactured listed products, the listing becomes the code. Get the manual for that Fp and you have your answer. Thom, section R1001 is for masonry fireplaces--not factory built units. The code states for manufactured units you must install listed units and install them in accordance with the listing. R1001 does not apply.

BTW-photo appears to be a Heatilator gas Novus Fp.

HTH

Thom Walker
06-21-2007, 07:43 AM
Thanks, Bob. As in many of the code cases, this is one where the section on manufactured fireplaces should specifically refer back to R1001 not applying. JMO

Jerry Peck
06-21-2007, 02:34 PM
regarding the air kit ducts, most mfrs. simply call for a Class1 duct, which means a flame spread of 25 or less. A lot of AHJs will allow the flex slinkies but require rigid as it penetrates a fireblock.

I was pointing out the difference between those plastic/foil slinkies and flexible aluminum duct.

Which (or both) do they allow?

Thom Walker
06-22-2007, 06:20 AM
.....The floor protection is a function of the testing. The ANSI Z21.88 std for vented room heaters allows floor temps. up to 117F above the ambient room temp. This is based upon test room conditions but as far as you guys are concerned, if the listed instructions don't require floor protection, then it doesn't--period. ..... Yes, there are some gas fireplaces that do require a non-combustible hearth extension. Typically, these are high BTU input radiant heaters with no convection chamber. Take for example the Heat&Glo Escape. When installed flat on the floor, it requires a non-comb. protection 12"x36". If it is mounted 4" off the floor, it does not require any floor protection.

With manufactured listed products, the listing becomes the code. Get the manual for that Fp and you have your answer. Thom, section R1001 is for masonry fireplaces--not factory built units. The code states for manufactured units you must install listed units and install them in accordance with the listing. R1001 does not apply. HTH

Bob, would you then suggest that missing installation instructions and operating instructions become part of the call out items of the inspection? I doubt that 10% of those I see still have either.

Richard Stanley
06-22-2007, 07:06 AM
There may be manufactured units that do not require a hearth extension - I have yet to read the instructions for one. I find hearth extensions that are NOT distinguishable from the surrounding floor area frequently.. I'll continue to report them as a defect until someone shows me differently. About the only time a manual is present is in a new build (sometimes).

Bob Harper
06-22-2007, 07:24 AM
We have discussed this several times here so I ask that you go into the archives and read more commentary there.

My recommendation is to alert the homeowner/buyer/ Realtor that without the manual, you will be limited in your report. Therefore, it is in everyone's best interest for them to either dig it up or go online and have one printed out before you arrive.

Always, ALWAYS record the make, model, serial number and if evident, mfg date code. Manuals change over time. The Heatilator Novus basic gas direct vent fireplace is the largest selling fireplace in history. Don't you think there have been some changes to that unit and its requirements over the years?

Jerry, unfortunately as long as it carries that Class 1 rating, most mfrs. will allow those flimsy slinkies. Some are just mylar scrim with a few thousandths of aluminum foil over it. Others are just the foil yet still feel like Jiffy Pop. The heavier dryer vent hose is a little more substantial but rigid 26 gauge galv. is the best.

Richard, you must not have read the instructions for gas direct vents. All woodburners require floor protection--both as noncombustible and with the specified insulating value. However, as I spelled out in the ANSI test std., as long as that floor does not rise above 117F above room temp.in the test, that unit does not require floor protection and to call it out for those units puts you at risk. If the listing does not require floor protection nor does any local ordinance in the codes, then to call for one in a home inspection report is improper, you will be liable and can easily be discredited.

If you don't know and don't have access to the manual, you can always put into your report that you suspect there may be a conflict on the floor protection or a clearance or whatever else and you recommend a specialist inspect it. However, if you call for such inspections all the time and routinely it comes back there isn't a blooiming thing wrong, you will begin to lose face with the Realtors, which could take years to rebuild.

Thom, it is not up to the mfr to state which codes do Not apply but up to you to know which Do apply. The codes require a listed appliance be installed in accordance with its listing. There are a few other areas where the code applies to Fp installations you'll need to be up on, esp. fireblocking and gas piping.

HTH,
Bob