Can I use PVC instead of ABS for DWV?

[AuntieLori]

Here in Central Florida it is impossible to find ABS pipe and fittings. I thought I could order from Lowe's but they won't ship the pipe! So I need to know exactly why I cannot use PVC instead for my drain/waste/vent system? I understand I need to use a transition cement for any abs fittings on my tanks. Has anyone replumb end using PVC and pex and had any problems later? I hope to drag this thing around the country once it's finally done.

I had hoped to reuse a lot of the ABS but discovered that many of the fittings leak like crazy.

Thanks for your input.

[khollister]

Try Ferguson Supply - I believe there is one in Altamonte Springs. I imagine the issue with PVC is weight


Keith
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[Thalweg]

I used PVC for everything that I replaced. I found a threaded ABS union, and screwed a threaded PVC union on the other side for the transition. I wasn't sure if the all-purpose glue would work between the two types of plastic. So the threaded transition made sense to me.

I've been told that ABS is getting hard to find. Apparently it has something to do with emissions from the manufacturing process.

[xrvr]

A Google search shows the abs available at Home Depot on Gainesville..

[TheGreatleys]

Home depot has special ordered ABS for me for pickup in store. That said, I don't see any reason you couldn't use PVC. Many on here do. IMO the additional weight is negligible. Properly glued, it shouldn't come apart even under flexing. Make sure you cut square, remove any burrs, and start with clean pipe. Use primer on both surfaces, then glue on both surfaces before the primer dries and assemble as quickly as possible. When you assemble a joint, press straight in then twist 1/4 turn, and hold for 30-60 seconds until the glue sets. Especially with larger diameter pipe, the joint likes to push back out if you don't hold it together long enough. The 1/4 turn helps ensure even glue coverage throughout the joint.

PEX seems to be the preferred material for fresh plumbing in rv renovations. Just whatever you do, don't use CPVC (yellow rigid pipe). It gets brittle as it ages.

[Jammer]

I've used both for various stuff.

I find that the main practical advantage of ABS is that the cement joints are much more reliable. The cement just works that much better. There's no primer to fuss with, and in my experience the likelihood of a leaking joint is lower. They also seem to develop full strength more quickly.

[Zil]

Plumbing forever. PVC is/was more expensive than ABS. PVC will work just fine. Special glue will work fine on the transition.

[TxDave]

Just finished redoing all of the plumbing on my 1971 Sovereign with PEX and PVC. Towed a couple of times since then. No issues.

[streaminwild]

Originally Posted by TheGreatleys

Home depot has special ordered ABS for me for pickup in store. That said, I don't see any reason you couldn't use PVC. Many on here do. IMO the additional weight is negligible. Properly glued, it shouldn't come apart even under flexing. Make sure you cut square, remove any burrs, and start with clean pipe. Use primer on both surfaces, then glue on both surfaces before the primer dries and assemble as quickly as possible. When you assemble a joint, press straight in then twist 1/4 turn, and hold for 30-60 seconds until the glue sets. Especially with larger diameter pipe, the joint likes to push back out if you don't hold it together long enough. The 1/4 turn helps ensure even glue coverage throughout the joint.

PEX seems to be the preferred material for fresh plumbing in rv renovations. Just whatever you do, don't use CPVC (yellow rigid pipe). It gets brittle as it ages.

X2 You know exactly what to do.

[Boxite]

And also don't use styrene above ground.

The white PVC is not long-lived in UV/sunlight.

[AuntieLori]

Ferguson's Plumbing told me I probably wouldn't find ABS around here but they recommended a mobile home supplier. Ray's Mobile Home Repair on East Colonial in Orlando had a small amount of ABS fittings. But nowhere near the variety I needed. However I found a place in Leesburg that had almost all the fittings and the pipe - Pat's Sales. They are a mobile home supply store. The plumbing guy was fantastic. I took all my pieces in and he matched all the fittings for me and when he didn't have an exact match he was able to make suggestions which gave me the same result. There was only one fitting he didn't have which was a 2" wye fitting and I ordered that on Amazon. I figured that since Airstream and the other RV manufacturers were still using ABS that I should do the same.

[khollister]

Interesting. I'm thinking I should throw a couple sections of ABS pipe in the back of the truck before I come back for the season from VA since the stuff is everywhere up there. Never know when I might need to repair something.

Glad to hear Fergusons put you on the right trail.

Joining ABS and PVC is somewhat controversial. Even though a transition solvent exists, local building codes are inconsistent on whether such joints are permitted. I expect the root of the issue is the different coefficient of expansion between ABS and PVC.


Keith
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[TG Twinkie]

If you have doubts about gluing ABS and PVC together. Just use a Fernco coupler. This method also allows for a much easier method of disassembly in the event of future repairs.