WH vent termination from headwall

[Clay White]

.........

[Billy Stephens]

Would you guys write this up? .

Clay.

I would not.

[Jerry Peck]

Yes, I would write it up if it is within 8 feet of the wall and not at least 2 feet above it.

At the height that vent *already* is, guy wires may be necessary, especially when making it taller to be at least 2 feet higher than that roof within 8 feet.

[Billy Stephens]

Yes, I would write it up if it is within 8 feet of the wall and not at least 2 feet above it.

At the height that vent *already* is, guy wires may be necessary, especially when making it taller to be at least 2 feet higher than that roof within 8 feet.


OK I'm hitting 0 for 2 back to the books. ;)

[Billy Stephens]

Clay,
Not Sure What your locale requirements are. This is what I have from IRC 2003

M1804.2.3 Natural draft appliances.Vents for natural draft appliances shall terminate at least 5 feet above the highest connected appliance outlet,and natural draft gas vents serving wall furnaces shall terminate at least to an elevation at least 12 feet above the bottom of the furnace

M.1804.2.4 Type L vent. Type L venting systems shall conform to UL641. Such vents shall terminate with the vent manufactures installation instructions not less than 2 feet above the roof and not less than 2 feet above any portion of the building within 10 feet.

From the Book (not the lip) :)

[John Arnold]

Billy - Neither of those address the question: What is the minimum distance above the roof the vent can discharge? Jerry is right, of course. If the vent is less than 8 feet from the wall, it must go at least two feet above the higher roof. I don't have the code reference - it is upstairs and I'm lazy and my back hurts.

[Billy Stephens]

John A.
Thanks,
I'm not disputing JP. Just going through the book looks like I need it.:D

[Billy Stephens]

thanks.

the vent height (right now) is about 4' 10"....once above 5 feet, proper securing would be needed, correct?

Come on Clay,

Welcome to Code Check- Help With Building Codes (http://www.codecheck.com)

[Jerry Peck]

John A.
Thanks,
I'm not disputing JP. Just going through the book looks like I need it.:D

Billy,

Here is a direction finder:

IRC G2427.6.4.2, and don't miss the "or" in there.

[Billy Stephens]

Billy,

Here is a direction finder:

IRC G2427.6.4.2, and don't miss the "or" in there.r

Mr. Peck,

Thanks it's under G2427.6.5 in IRC 2003.Vertical wall or similar obstruction.8 feet. My location just went to 2003 last year.I don't look for an update for 3-4 years.

[Jerry Peck]

Billy,

That section is a bit tricky to read because ...

If there is a vertical wall or obstruction *within 8 feet*, the vent must be 2 feet above it, but, because it is within 8 feet of the wall, the vent must also be 2 feet above any part of the structure within 10 feet, thus, the correct thinking is that it must be 2 feet higher than the obstruction within 8 feet and enough higher to also put the top of the vent 2 feet higher than any part of the structure within 10 feet - which may mean the vent needs to be 5 feet high above the higher roof (considering a 6:12 slope, 2 feet horizontally is 1 foot high, 10 feet horizontally is 5 feet high).

In the photo shown, that means that vent would need to be about 10 feet high above the roof - which means guying that sucker off at a couple of heights up the vent, and that it will look U-G-L-Y. :D

[Tom Munds]

I agree with Jerry 8' and 2'

[Jerry Peck]

We all have remembered the 3-2-10 rule for chimneys:
3' high above the roof minimum and 2' high above any part of any structure within 10'.

I just thought of this new rule for vents which I will call the 8-2-10 rule:
8' from any vertical obstruction or 2' higher than the obstruction and any part of the structure within 10'.

~~~~~~~~

For chimneys, the 3-2-10 rule - 3' high minimum and 2' higher than anything within 10'.

For vents, the 8-2-10 rule - 8' from or 2' higher than anything within 10'.

What do you guys think?

The 8-2-10 rule for vents.

[Tom Munds]

I think that sounds good. I think the within 10' only applies ( in venting) to the type "l" oil vents though. No mention , to my knowledge, of 10' comes up in code-check( 4th edition- pg 22 bottom of left column)
What do you think of the codre check books anyway?

[Jerry Peck]

I think that sounds good. I think the within 10' only applies ( in venting) to the type "l" oil vents though.

Applies to all "vents" I believe, I know it also applies to Type B Gas Vents.


No mention , to my knowledge, of 10' comes up in code-check( 4th edition- pg 22 bottom of left column)
What do you think of the codre check books anyway?

Can't say, I don't own them.

[Tom Munds]

Applies to all "vents" I believe, I know it also applies to Type B Gas Vents.



Can't say, I don't own them.
The books seem to be good for me but If you are right it is not listed under "B" vent about 10' thing. How about IRC 03 2427.6.5 ?Let me know what you find out.

[Jerry Peck]

Tom,

I posted this above on 10-28:

Billy,

Here is a direction finder:

IRC G2427.6.4.2, and don't miss the "or" in there.

Here is the text:
(underlining is mine)

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.
- 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.
- 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.

Read the "OR", it is important, one of the biggest little words you will see.