Hard PVC vs Flex Pipe for Basement Return/Drain

[Vapour1ze]

I am going to be beginning my plumbing endeavor on my basement sump to the display (1st floor) sometime in the next few weeks. My father is a plumber and he wants to hard plumb it all. Let him do it? Or should I suggest flex? He said flex looks like crap and he doesn't like it. Advice? I'm going to be installing a manifold as well right after the return.

What about primer/glue? Reef safe once cured? Do an initial flush with vinegar?

[myram]

I like flex since there are no hard angles or corners for the water to flow thru.

Make sure your drain line remains at a downward slop at all times, no horizontal runs. They cause back pressure and messes with the overflow.

[DasCamel]

Small piece of flex(few feet) right after the return pump to reduce vibration is always nice, but either way works.

[shermanator]

I'm plumbing a basement sump now (very slow, not making much progress), but I'm using Spa Flex PVC for the floor of my DT to the ceiling above the sump. It avoids using a lot of fittings and dramatically lowers head pressure (flex vs the number of 90s I would have used) so that I can hopefully downsize the external pump.

I'm hard plumbing the wall areas (up to DT and down to sump) because I think it looks nicer and is easier to keep out of the way. And I am using silicone tubing to connect the 6" between hard PVC and pumps to keep down vibration.

I only use glue (usually Oatey Rain-R-Shine) for flex and I don't primer it. When I used primer, I could break the joints easily. There are several threads on glues and techniques to use flex pvc.

[ca1ore]

I just find flex PVC easier to run. Whether it significantly reduces pressure on the pump or not ..... would have to actually test that one. Less elbows, but also slightly smaller ID.

[shermanator]

Originally Posted by ca1ore

I just find flex PVC easier to run. Whether it significantly reduces pressure on the pump or not ..... would have to actually test that one. Less elbows, but also slightly smaller ID.

Good point. I'm using schedule 80 for the hard lines (because I like how it looks), so the head pressure for me is better with flex (vs elbows). But if I really cared about head pressure, I wouldn't use schedule 80 in the first place.

[ca1ore]

I'm with you. I used it in part because of presumed head pressure reductions too. Just want folks to understand that it isn't likely to be dramatic. - pumping against gravity still carries the day.

[James77]

Originally Posted by Vapour1ze

What about primer/glue? Reef safe once cured? Do an initial flush with vinegar?

Yes, reef safe when cured. It is fully cured within about 1-2 hours for the typical temp and humidity ranges for pipes up to 1.25"

No need to flush with vinegar....