I have an external ABS plumbing vent pipe in need of being rerouted around a window. Project seemed easy enough, just get some ABS pipe, elbows, cement. Now I'm finding ABS nearly impossible to locate. Big box stores like Lowes and HD don't stock it. Ditto for plumbing supply stores.
Is there a way to transition ABS to PVC? At least then PVC components would be available.
How about a Fernco coupling?
There is adhesive rated for PVC to ABS and iirc, the sizes are the same. And for this application, there will be no pressure, so I don't think I'd worry.
I think it depends on where you are located. Individual Home Depot and Lowes stores sometimes stock different items (and intentionally don't stock others) based what the local codes in their town request or allow. For example, one store may state, "We don't stock XYZ product because local codes do not allow it to be used." I think that they do that in some towns for "political" reasons and to keep the peace with local code officials, even though I think they could legally sell whatever they want in any store.
I can't imagine a plumbing supply place not selling ABS.
Where are you located?
Long Island, NY
Plumbing supply store said they don't stock ABS any more and they are the largest plumbing supply in the area. They did say some HVAC suppliers might but being a holiday weekend it seemed wise to begin checking alternatives.
Hi Jim,
The preference for ABS vs PVC seems to be a regional thing. Around here (Washington State) ABS is the norm and it's rare to find PVC. But, I still chose PVC which was only stocked at Lowes stores.
If you could track down a single ABS fitting, you could use a male ABS adapter with a female PVC adapter and thread them together. Or the other way around (male PVC to female ABS).
Otherwise, your best bet would be a Fernco style coupling. These are rubber couplings you slip over the end of each pipe and tighten down two large band clamps. They're used frequently for joining different types of pipe and for joining nohub cast iron.
I used PVC for our drain plumbing, but didn't want a big white pipe sticking out of the roof. So I used a fernco coupling to transition to a short piece of ABS pipe. I didn't have the vertical space needed to use the male/female fittings.
One final thing to think about... As far as I know, standard PVC does not have any UV protection built-in, so the pipe could become brittle and break down in exposed sunlight. You may need to paint the pipe to protect it.
Take care,
Anthony Watson
Since the whole idea behind a vent is to allow air into the drain piping so that the draining water doesn't suck the P-trap dry, you may be able to use an air admittance valve here instead of running that vent around the window.
Air admittance valves are used exactly for situations like this where using a vent pipe isn't practical.
[image:An air admittance valve has to be down stream of, and at least 4 inches above the p-trap, but check your local plumbing code. Your local code may be different.
I am in Eastern Washington state, town of 2,000. We have 3 different stores (Ace, Grange, and lumberyard) each has racks of both ABS and PVC.
Good point about the sun damage. I was going to warn him if no one else did.
Harry K
Generally it is good advise to mount them 4 inches ABOVE the maximum water level in the sink in question
I agree, and in a bathroom you can always put the AAV in the wall behind the medicine cabinet. But, this is a kitchen and there typically isn't anything a person could hide the AAV behind. So, in this case, I think he'd just have to settle for it being as high up under the counter top as possible.
Canada may permit you to put an AAV in a wall. In the USA, it is _NOT_ permitted unless you have a panel, even then, depending on the local code, it may not be allowed. I know for a fact you cannot put one behind a medicine chest in the USA.
Harry,
That must be nice. I'm in SW Washington state (near Portland, OR). Home Depot, all of the small hardware stores like Ace and DoItBest, and even the dedicated plumbing store only stock ABS pipe (for DWV pipe). Lowes is the only place I have been able to find PVC locally.
I chose PVC because I was already familiar working with it for supply plumbing, and the only time I used ABS I had a leak (probably just coincidence, but I didn't want to chance it). It also seemed like ABS was being phased out in other parts of the country, and I seem to remember reading something about PVC being stronger (not that you really need strength for a drain pipe).
I've never really heard whether ABS has UV protection, but it's sticking out of every roof in the county so I figured it would be OK. :)
Anthony Watson
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.