ABS fittings

In Canada, it's all ABS (inside a bldg.) and it's been used in residential construction since the 1950s. In the US, I think it depends entirely on the local jurisdiction. I've read that ABS is better in cold climates, but then I also read that ABS is required in California.

PVC expands & contracts from temp. changes a lot more than ABS and PVC is more brittle and for these reasons alone, maybe ABS is better in an RV? There is more of a procedure required for proper gluing (solvent welding) of PVC that requires the use of a primer before the cement and you have to hold a joint together for up to about 30 seconds. I can see this increasing the chances of failed joints by improper procedure at an RV plant. Gluing ABS together is much easier.

It seems like there were some problems with ABS because it was being manufactured with re-processed resin and now Calif. at least has new code requirements. California ABS code requirements Maybe problems with ABS prompted a switch to PVC? When you look at the various properties between the two, in the overall, one doesn't appear to be far superior and it would be interesting to know why some jurisdictions want only one or the other.

You would think that ABS being successfully used in a dwelling (camper) that is undergoing constant seismic activity (towing) would make it suitable for a fixed structure. My house was plumbed with ABS drain pipe when it was converted to sewer before my purchase. So far so good after 25+ years.
I did need some ABS when I replaced the black tank in the camper last year. The only place I've seen it locally is the RV dealer. Nothing in the big box stores.

ernie1 wrote:
Why is it that some areas of the country use abs and some use pvc for drain lines? Does it have to do with toxic fumes that occur when there is a house fire? We only use abs here in California for drain, waste and vent lines. Not sure if I could even find any pvc drain fittings.

ABS is being phased out in favor of PVC because it is more costly to produce. There were also a rash of ABS failures in the late 80's, early 90's. The market has a long memory for this type of failure.

Any plastic is not going to be good in a fire. By the time your PVC or ABS pipe is burning, you will have more severe things to deal with, in the event of a household fire.

Why is it that some areas of the country use abs and some use pvc for drain lines? Does it have to do with toxic fumes that occur when there is a house fire? We only use abs here in California for drain, waste and vent lines. Not sure if I could even find any pvc drain fittings.

Consider a rubber fitting. We have elbows, tees and straight joints in our local hardware store. They are nicely made with hose clamps fitted. The thing is, the ABS part probably broke because the ABS piping is too rigid for a unit that goes on the road. A rubber part will greatly increase flexibility and lifetime between cracks.

If all you can find are PVC fittings you can join ABS directly to PVC if you use "transition" cement. You could also use a Fernco fitting (a rubber collar that has clamps) or transition fittings like in the below link:

transition fittings You can see a Fernco fitting in the bottom of the photo. Available at many hardware stores and HD (at least here).

Fernco fittings These can be used to connect pipes of slightly different diameters and are also available as reducers for larger difference in pipe diameters.

Another thing you could try is going to a plumbing wholesaler.

Lowes has them. They even had the same brand P-trap that was used on my tub drain so I didn't have to replace both halves.

Since it is a drain line you might try a repair.. GOOP seems to stick to that stuff in my experience,, Work it into the crack and smooth a small mount for about 1/2 inch either side of crack and let it dry overnight. Fill tank with at least 10 gallon of FRESH water and dump.. Odds are it won't leak

This gives you a lot of time to find a proper coupler.

It's a regional thing. I believe it is very common out west, but around here RV places are the only sources. Big Box stores stopped carrying it a long time ago.

Yes, some of the big box stores are not carrying ABS. Home Depot stores are almost 100% vendor-supplied so those were the first not to carry ABS in this area.

Any plumbing supply house will have whatever ABS you need.