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monkeystomach
07-19-2010, 09:56 AM
Hi everyone,

I’m new here, as you can tell by my post count, and I do have some problems I hope you all can help me with.

First… I tried searching “pex” using the search tool, but every time it says Sorry - no matches. Please try some different terms… I must be searching wrong because I cannot believe that pex has not been talked about somewhere on this site…


But my main problems are as followed:

I am trying to install this pedestal sink where a vanity use to be. Since I already ripped all of the drywall down I was going to move the water supply pipes and valves closer together so they would hide behind the pedestal.

http://i138.photobucket.com/albums/q276/monkeystomach/0717001605.jpg





Since I’m a regular DIY homeowner, I opted for pex and this is what I have now…

http://i138.photobucket.com/albums/q276/monkeystomach/0718001811.jpg

So… I know that my cold water (on the right) cannot stay like that… can it? Is that too much bend in the pex? I do not want to put too much pressure on the fitting. I might have to redo my vent and drain system to get it to work correctly... opinions?

What about my hot water line? Do I need to attach it to something else, or will the screws in the fitting at the top be enough? Is that angle okay on the hot water line?

After reading some articles and posts about PEX, I’m a little worried about it now. I might not have all the facts straight but here it goes (please correct me if I’m wrong).
PEX is great, but the fittings are where the problem is. The fittings use to be a lot thinner which caused them to snap and spray water everywhere. The fittings are now much thicker and breaking is not a problem. However, with thicker fittings there is less water flow…?

If that is correct, and I have ½ copper, should I use ¾ PEX to get the same flow? Will I notice a difference?


Sorry for the long crazy post.

Thanks,
Monkey

jadnashua
07-19-2010, 10:26 AM
The supplies for the sink are fine...pex that diameter can probably be bent into a 6" radius, and you've got nowhere near that angle. Ensure you screw it to the blocking. To minimize the stress right at the fitting, there's no reason why you can't tilt the dog-eared fitting to the incoming pipe, if you wish.

For the sink, the 1/2" pex will be fine since the flow restrictors required in any vanity faucet will restrict the flow to about 2.2 gpm. But, you may notice a difference if using a multi-head shower system or filling the tub. There, you may want to convert to 3/4, then back to 1/2" at the valve. While a showerhead is restricted to about the same as the vanity, with 1/2" pex supplies to the tub, you will decrease the flow rate, probably noticably unless you go to 3/4" (no big need for a 3/4" valve, use an adapter to get it back down to 1/2"). that being said, mine is plumbed with 1/2" pex, but they used Wirsbo/Uphonor, which uses the expander tool and their fittings. This system does not use crimp rings, the tool is inserted into the end of the pipe, expanded, then you quickly insert the fitting and the pipe collapses around the fitting. Because of the expansion, the flow restriction isn't anywhere near as great since the fitting OD and ID can be larger.

Terry
07-19-2010, 10:30 AM
You will need to screw the fittings down to the wood if you expect to thread in brass nipples for the shutoffs.

The bend on the PEX is fine. We bend it all the time.

1/2" to a lav faucet is plenty. You have a aerator on the faucet that restricts to 1.5 or 2.0 gallons anyway.

If PEX was such a problem, we wouldn't be installing it, and the builders wouldn't be asking for it.

Since you have the wall board out, now is a good time to put the wood backing in for the lav.

Wally Hays
07-19-2010, 03:35 PM
You will need to screw the fittings down to the wood if you expect to thread in brass nipples for the shutoffs.

The bend on the PEX is fine. We bend it all the time.

1/2" to a lav faucet is plenty. You have a aerator on the faucet that restricts to 1.5 or 2.0 gallons anyway.

If PEX was such a problem, we wouldn't be installing it, and the builders wouldn't be asking for it.

Since you have the wall board out, now is a good time to put the wood backing in for the lav.

In my experience most builders are only interested in cost and getting in and out as fast as possible.

monkeystomach
07-22-2010, 05:42 PM
thanks for the help guys.

monkeystomach
07-23-2010, 04:56 PM
Hi guys.
Before I put the last few screws and clamps on the pipe system and put up the drywall I just wanted to check again on the cold water pipe (on the right) to make sure that it is okay and not going to snap and flood my house :)

http://i138.photobucket.com/albums/q276/monkeystomach/0723001823a.jpg
http://i138.photobucket.com/albums/q276/monkeystomach/0723001823.jpg
http://i138.photobucket.com/albums/q276/monkeystomach/0723001822b.jpg

monkeystomach
07-23-2010, 04:57 PM
some more...

http://i138.photobucket.com/albums/q276/monkeystomach/0723001822a.jpg
http://i138.photobucket.com/albums/q276/monkeystomach/0723001822.jpg
http://i138.photobucket.com/albums/q276/monkeystomach/0723001821c.jpg
http://i138.photobucket.com/albums/q276/monkeystomach/0723001821b.jpg

monkeystomach
07-23-2010, 04:58 PM
http://i138.photobucket.com/albums/q276/monkeystomach/0723001821a.jpg
http://i138.photobucket.com/albums/q276/monkeystomach/0723001821.jpg

sorry for the cell phone pics, but they are better than nothing i guess...
Thanks again!

Redwood
07-23-2010, 06:44 PM
Nope! Your fine with the PEX!

I'd be more concerned about the ABS with all the cement the plumber slathered on it...
Sometimes excessive cement can cause joint failure.

As Terry stated make sure you put in a backer board for the lav sink to screw into so it doesn't rip off the wall when someone leans on it....

Terry
07-24-2010, 02:03 AM
Redwood, how can you say that when there are only a few pictures of the PEX to look at.
There were a few angles I would have liked to have seen.

Maybe one angle from the Lunar Lander, or from that tall tree in my parents yard.
You can't be too careful.

shacko
07-24-2010, 01:42 PM
I hope you roughed that in to the sinks dimensions that should of come with it, otherwise you will be a unhappy camper when it comes time to hook it up, luck.

Redwood
07-24-2010, 03:04 PM
Redwood, how can you say that when there are only a few pictures of the PEX to look at.
There were a few angles I would have liked to have seen.

Maybe one angle from the Lunar Lander, or from that tall tree in my parents yard.
You can't be too careful.

Yea maybe 5-10 more from angles not covered yet...