Removing a sink

[Lorne]

The living room has a 6-foot wide wet bar area with a sink at one end. We've never used the faucets and sink, so we plan to remove it all and replace the countertop to give us a usable 6-foot flat surface.

The house does not have copper pipe - all of the supply lines are grey PVC. For this particular sink, the hot and cold supply come out of the floor and go directly to the faucet. I don't have access to the connection in the basement because the ceiling is finished. So what I have is two tubes coming from the floor.

Removing the sink seems easy, and closing off the drain doesn't look that complicated. But clearly I have to securely close off these supply lines, and make sure the suckers don't leak. Since I can't do it at source in the basement, I have to install some kind of valves under the sink to shut it all off. I've never done this or seen it done.

So before I go to the home depot and ask for advice there, what wisdom can this group offer me?

Thanks in advance

[I-zheet M'drurz]

Cut 'em and cap 'em.

Assuming you have a saw of some sort, you'll need 2 caps (buy 4, in case you screw up, they're not removable) PVC cleaner/primer and PVC adhesive/cement.

Turn off the main water supply valve and the one going in to your water heater, open the faucets and drain as much water as possible before you cut the pipes. DON'T try to cut them too close to the floor, leave a nice long stub in case the next home owner wants to use them again. In fact, if you screw up the next step, YOU will have to cut some more off, so leave as much stub as you can stand (it's going to be hidden under the sink anyway, right?)

If you have NEVER worked with PVC pipe and adhesive before, please do some more research or get somebody to help who is experienced. While it's a fairly simple process, there is no room for error, the adhesive sets up QUICKLY, and if you don't get it coated properly you will have leaks.

Cut the pipes with just about any saw (jig-, circular-, chain- ) DRY them thoroughly, CLEAN them thoroughly, and use plenty of adhesive to apply the caps. By all means have somebody standing there looking for leaks as you turn the water back on. You could use valves insted of caps, but that leaves you exposed to somebody (kids, grandkids?) opening them by accident and sending you for the mop (or the homeowner's insurance).

[Dan G]

Go back to the basement. I would think there will be some valves on those lines at some point, maybe not right under them. Look for an access panel in the bottom of the cabinet or under the cabinet.

You will need to be able to stop the water flow to disconnect and to modify. It may require killing the entire house, usually back where the hot water tank is.

If you cannot find any localized shutoffs, you will need to know what size pipe with which you are dealing. You can buy two compression angle stops ($2 or $3 each). You are probably dealing with either 1/2" supply lines or 3/8" lines. You can install the stops on either size pipe and turn off the valve. This is not the ideal method, but will work well and allow for future re-use of the system.

[Mistercmk]

He might want to use a valve and then put a cap on the end of the valve.

[Joe Bobst]

Not all plastic is PVC and gray colored PVC is more commonly found in UV resistant electrical conduit. In other words, before cutting and capping, make sure that your pipes are PVC, CPVC, PEX, ABS or whatever and apply the correct cleaner and solvent cement. Materials are often identified on the pipe itself with markings every foot or so. Look for the ID and choose the right repair system and you should have an easy fix. Good luck.

Joe

[Lorne]

And here's the rest of the story. It was a plumbing disaster worthy of your most hearty ribbing. Home Depot guy said you don't cap it, you put a shut off valve on it and leave the valve shut off. So I tried, without success, to install the shutoff valve on my now hacked off supply lines. Each time I turned the water on, it leaked like crazy. And then in what will not be noted as my finest hour as a plumber, I further tightened one of the lines only to have the valve fly off.

It's amazing how much water pressure there is in a residential area.

2.5 hours, $11. Failure.

I called a plumber in. He told me that the valves I had been sold would not work attaching to a poly-B line - if I somehow managed to get them leak-free, there's no way he's sleep well knowing they were there. Could come off at any time. He re-cut the line correctly, attached a brass poly-B to PAX connector, crimping both sides properly with these rings, using a very expensive crimping tool. Then he connected a proper valve to the PAX side, crimping again. Repeat on the other supply line.

20 minutes, $132. Success.

I feel like a putz. Take your shots - they are well deserved.