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I have a waste vent terminal that will be 2 m below a window (2 storey house). Can I leave this terminal there, or should I extend it above the windows (adding 3.5 m to it and having an ugly pipe on the side of my house)?

What is up to code? What is manageable? I'm in Brazil and our code doesn't mention clearance to vents below windows.

Edit Rough sketch (vent in red 2m below the two windows in blue and about 1.5m above the doors in brown): enter image description here

Can I left the vent terminal in this position, or should I extend it above the root line?

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can you please post a picture with pointers where you want to make the change? it is very hard to visualize – amphibient Apr 10 '14 at 21:20
Added a sketch per request. – Luiz Borges Apr 10 '14 at 22:14
is this pipe going on the outside of the wall? – amphibient Apr 10 '14 at 22:16
Yes, it goes along the wall (brick wall) coming out of the floor (near the first waste inspection box) – Luiz Borges Apr 10 '14 at 22:23
I'll take "ugly pipe" over "the lovely smell of sewer gas wafting in the window" 10 times out of 10. – Ecnerwal Apr 11 '14 at 3:59
up vote 4 down vote accepted

Other codes may vary, but according to the 2012 International Residential and International Plumbing Code:

P3103.5 Location of vent terminal. An open vent terminal from a drainage system shall not be located less than 4 feet (1219 mm) directly beneath any door, openable window, or other air intake opening of the building or of an adjacent building, nor shall any such vent terminal be within 10 feet (3048 mm) horizontally of such an opening unless it is not less than 3 feet (914 mm) above the top of such opening.

In my local jurisdiction I would be required to extend the vent above the roof line.

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How is that, different than that: publicecodes.cyberregs.com/icod/ipc/2012/… – Luiz Borges Apr 10 '14 at 23:47
@LuizBorges Different code authorities often use the same language with different numbers. For example, the same section in the California code is 906.2. What they are trying to avoid is drawing sewer gases into the house when the windows are open. – Comintern Apr 10 '14 at 23:51
I meant, the text from "903.5 Location of vent terminal" (my link) is different from P3103.5 (your link). How is that? – Luiz Borges Apr 11 '14 at 0:43
@LuizBorges - Ahhh... scanned it too quickly. The code you linked is a little less stringent. Both allow a vent to be below a window if there is 10 feet of horizontal separation. The IRIPC requires that it be also be at least 4 feet lower. So the IRIPC would allow a vent 10 feet to one side of a window as long as it was at least 4 feet below it. – Comintern Apr 11 '14 at 0:55
Actually the code you posted doesn't require the 10 feet horizontal separation, it just says it can't be "less than 4 feet", so an opening 5 feet below would be fine by your post. – Luiz Borges Apr 11 '14 at 3:59

Rather than take any chances on sewer gasses being pulled into your home I would extend the pipe to be above the roof line.

You can then prep the surface of said pipe and paint it so it will not be "ugly". One paint idea is to use a color that is so similar to the wall color that you do not see the pipe from a distance. The other idea is to paint in a color that matches some other contrast feature in your house color such as might be used for rain spouts or trim.

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I agree with this. And they do sell architectural piping that would be suitable for vents and look good. – DMoore Apr 11 '14 at 15:24
I thought about painting it in contrast color (like some other parts of the house will be) if I had to extend it. I think this is what I will probably do. Just to be on the safer (and less smelly) side of the matter. – Luiz Borges Apr 11 '14 at 17:03

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