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Jon mackay
05-15-2007, 09:46 AM
I came accross a chimney that did not appear to meet clearance requirements but I was not sure if the requirements for gas fireplaces was different. Any help would be appreciated.

Distance to adjacent roof 5'-0"
Distance to adjacent window 8'-0"

Rick Cantrell
05-15-2007, 11:51 AM
Min 2' above any thing 10' or closer and at least 3' above the roof.
Ir it is 30" wide or more it needs a cricket

Jon mackay
05-15-2007, 12:03 PM
Ok, so the same standards apply then even though it's for a gas fireplace?

Rick Cantrell
05-15-2007, 01:19 PM
The clearance requirement is for the chimney, not for the fireplace.

Bob Harper
05-15-2007, 03:32 PM
Jon, I agree with Rick on the min. height and cricket. Appears to be right at 30" wide. From the side view, it appears there are two air kit intakes on either side of the gas line, which enters the rear of the firebox. From above, it appears this is a factory built fireplace with a faux brick chimney and two piece stone chase top that somebody sealed off the top of the air cooled pipe with sheetmetal then installed a direct vent liner kit.

Can you confirm this is a factory built Fp?
Model#?
Interior pics?

If it is a factory built woodburner with a gas insert installed, it does not meet the minimum height for most Fps per the listing I'll bet. That roof flashing or the lack thereof appears to be a mess. Is this real brick or 1/2" lick 'em & stick 'em?

I would recommend a Level II inspection. Looks as though they had water problems and I'll bet the insert was installed due to smoking problems.
Bob

Jerry Peck
05-15-2007, 05:19 PM
Min 2' above any thing 10' or closer and at least 3' above the roof.
Ir it is 30" wide or more it needs a cricket

I believe gas vents are 2 feet above a wall or similar vertical surface within 8 feet. And the 3 foot height does not apply to gas vents, the height would depend on the slope of the roof.

Those 3-2-10 rule is for "chimneys" not "gas vents".

Rick Cantrell
05-15-2007, 06:15 PM
What I see is a brick chimney, for what I presume to be a wood burning FP ( I could be wrong). Whether or not someone burns wood or gas in it now is secondary, it is (or was intended to be) a chimney for a wood burner. Being so it is wrong.

If I build a fireplace, but only burn birthday candles in it, is it a candle holder?

wayne soper
05-15-2007, 07:03 PM
Isn't there a chimney top to window height clearance issue here that we are overlooking. The top of this chimney is below the window top. Cannot be allowed.?

Jerry Peck
05-15-2007, 08:41 PM
What I see is a brick chimney, for what I presume to be a wood burning FP ( I could be wrong).

This was in the original post:

"but I was not sure if the requirements for gas fireplaces was different."

It makes a difference, yes it does.

"Whether or not someone burns wood or gas in it now is secondary, it is (or was intended to be) a chimney for a wood burner. Being so it is wrong."

One should not presume so much so quickly. :)

Jon mackay
05-16-2007, 07:32 AM
Now I'm really confused.

This is a gas fireplace (not sure of the model#) I have attached the interior picture.


The chimney is real brick with a tile liner and then a metal insert to the gas fireplace.

I was going to call out the fact that it is not high enough over the adjacent roof and that it discharges too close to the window (which will not be a problem if they raise it up past the adjacent roof).

Rick Cantrell
05-16-2007, 07:59 AM
Jerry
Clarify please

wood burning FP= 3-2-10

gas FP = gas appliance vent

wood burning burning FP with a gas FP inserted=?

Thanks

Michael Thomas
05-16-2007, 08:06 AM
For "gas appliances", height above roof and distance from walls:

see fig. 12 on page 8, and table 2 on page 9 here:

http://www.ventingpipe.com/catalogs/simpson/bvent.pdf

and fig 43 on page 21 here:

http://www.duravent.com/docs/instruct/shbook.pdf

David Banks
05-16-2007, 09:03 AM
IRC 2003. G2427.6.5(503.6.6 Gas Vent termination.
Above the roof surface with a listed cap or listed roof assembly. Gas vents 12 inches in size or smaller with listed caps shall be permitted to be terminated in accordance with figure G2427.6.5 provided such vents are at least 8 feet vertical wall or similar obstruction. All other gas vents shall terminate not less than 2 feet above the highest point where they pass through the roof and at least 2 feet higher than any other portion of the building within 10 feet.

Jon the way I interpret this, the last paragraph is your situation.

Jon mackay
05-16-2007, 09:34 AM
Thank you, I will feel a lot more comfortable calling that out now..

Jerry McCarthy
05-16-2007, 11:24 AM
This may help?

Jerry Peck
05-16-2007, 03:18 PM
This may help?

http://http://www.inspectionnews.net/home_inspection/attachments/fireplaces-chimneys-solid-fuel-burning-appliances-home-inspection-commercial-inspection/873d1179339848-gas-fireplace-chimney-clearance-vent-clearances.gif

Actually, that confuses the matter.

David posted the code (for 2003 I think).

This is the 2006 IRC code.

- G2427.6.4 (503.6.4) Gas vent termination. A gas vent shall terminate in accordance with one of the following:

- - 1. Gas vents that are 12 inches (305 mm) or less in size and located not less than 8 feet (2438 mm) from a vertical wall or similar obstruction shall terminate above the roof in accordance with Figure G2427.6.4. (Jerry's note: See chart for heights. Unlike the drawing posted, the distance for gas vents is 8 feet.)
- - 2. Gas vents that are over 12 inches (305 mm) in size or are located less than 8 feet (2438 mm) from a vertical wall or similar obstruction shall terminate not less than 2 feet (610 mm) above the highest point where they pass through the roof and not less than 2 feet (610 mm) above any portion of a building within 10 feet (3048 mm) horizontally. (Jerry's note: Note the "or", which means this also applies to 1. above. Now, once the 8 foot dimension has not been achieved, the 10 foot dimension kicks in - making it a tad more complex ... if you are 8 feet away, no problemo, however, if you are 2 feet from a side wall, not only must the gas vent stick up 2 feet higher than the roof above, it must also stick up high enough so it is 2 feet higher than that upper roof where within 10 feet of the gas vent. ANY SIZE gas vent.)
- - 3. As provided for direct-vent systems in Section G2427.2.1.
- - 4. As provided for appliances with integral vents in Section G2427.2.2.
- - 5. As provided for mechanical draft systems in Section G2427.3.3.


Note that the last part of 2. also applies to 1. - because of the "or".