[Stubits]

Thanks to all those who have helped thus far. I have decided I will move forward with repiping my house with Pex, but I have a couple of planning questions.

1) What size PEX should I use? I am thinking 1" from the main, 3/4" branches and then 1/2" to the fixtures? Does that make sense?

2) What is the best and most trusted/secure way to make the connections? Crimping? Compression?

3) I do not know how to sweat copper joints, but I will be connecting to copper in a number of places. What is the best way to connect PEX to copper without soldering? Most of these connections will be behind the walls.

4) Just a little nervous about running the PEX in the attic. I live in Washington, DC where it gets cold in the winter. The attic is of course unheated. Is it sufficient to insulate the pex with foam insulation? Currently the attic is uninsulated entirely, but I will be insulating it with fiberglass batting, would I want the pipes to run between two layers in the insulation? Under all the insulation? Above the insulation?

5) Finally, how often do I need to attach the Pex to a stud, etc. If I can manage to run the piping from my attic all the way to the basement utility room (two floors down) without having to open a wall, and therefore only attaching at the top and bottom of the run, is that OK?

Thanks!

[steven62]

Stubits,
The sizes you suggest sound right, but you would normally use whatever size you might use in CPVC pipe, if that helps.
I like compression fittings, but crimp rings have their place (tight fits etc.) and they are less expensive.
Attaching to copper will most likely involve sweating on a barb fitting for the PEX.
PEX will not freeze and burst, but insulating will keep the water flowing, especially in an attic, I would think. Keep your hangers loose, as PEX changes size 1.1" per 100' per every degree temp rise, so it needs to be able to move, or it will make noise.
Also, check with the manufacturer of the PEX you are using for the proper fittings. PEX is not yet made to a standard, (Although some are more or less to a voluntary standard) so the fittings from one brand may not fit another!

[Stubits]

Thanks so much for the info. Very much appreciated.

Are there any alternatives to sweating the fittings onto copper? Compression? Crimp? Sharkbite?

[ballengerb1]

All of the above but lets be clear, Sharkbite is a brand name and not a type of clamping. Watts and others also make similar fittings that slip into place and hold your connections. Compression should not be enclosed in a wall cavity but most codes will allow a Sharkbite or its equivalent.

[Stubits]

Ballenger:

Thanks for the clarification. I am confident you are comfortable sweating copper joints, but what is the best, most secure option otherwise?

Also, any thoughts on the other questions? Are you in agreement with Stevens 62?

Thanks!

[ballengerb1]

Steven seems on the money. You can crimp a PEX line but the crimper can run you $120 and its not always cost effective to try to rent them. Sharkbite connector are aound $5 each but no tools required, that's my route.

[Stubits]

OK, so you are saying I could actually do the whole repiping using sharkbites?

I was planning to crimp pex to pex and just use the sharkbites for pex to copper.

Sharkbites hold up over the long run? This will be a whole house repipe.

Also, how often does pex need to be tied down? One of the major runs involves going from my basement to my attic, probably about 40 ft or so, and it is possible I would just connect it at the top and bottom of the run, is that OK? Will the pex flop around or make noise?

[ballengerb1]

I think we need some of our plumbers to come on board regarding how longShakebites are good, I have only used them for about 5 years but Tom and Mark probably know better. I'll connect them to this question. On your last question, every 10' would be my approach.

[Stubits]

I guess another question might be, how tough is it to learn how to sweat pipes? I guess that would be the best approach, and in fact, there are only really 5, maybe 7, pex to copper connections?

Is it a skill I can learn? I hear if it works, it works, if it doesn't, you know right away, right?

[steven62]

Local codes may have a distance in mind for attachment, but it could conceivably go 40' up with attachment top & bottom.
The noise comes from it being confined but not immobilized, especially on the hot water side. If it has room to grow without rubbing much or bumping, it will make less noise. If it is confined it will tend to "creak" as it slowly slips past whatever is confining it, but it shouldn't flop as it is fairly stiff.
I like the idea of the Sharkbites, but never used them.

[ballengerb1]

I sent Tom and Mark a note but they are both offline at present. Sweating cooper isn't really rocket science. Clean the inisde of the female and outside of the male with a round brush or emery cloth. Apply flux to both, slide together. I'd recommend a cheap propane torch but when you buy your solder don't get electrical solder, buy plumbing solder. They look alike but aren't. You can also buy connectors that already have a rinfg of solder inside them. Heat the connection by directing your flame to the female fitting about a half inch away from the actual joint. Touch your solder to the joint and tap a few times until you see it starts to melt, remove the flame and feed solder in and around the joint until it wicks around the joint, wipe with a rag. When you are ready to test all of your connections have a friend or two help you watch for leaks and/or drips. If you have a leak all the water needs to be removed from the area to resolder. I am not a licensed plumber so my approach my not be accepted by all but when I get a leaker I first try just reheating and adding a touch more solder. Most plumbers would likely tell you to disassemble, clean and start over. I'm just too old to do that.

[Stubits]

Guys, this info in invaluable, I feel great about this project. We just bought our first home and I have been loving the opportunities to get my hands dirty.

Thanks.

I look forward to Tom and Mark's input!

[massplumber2008]

Stubits...

Bob asked me to pop over and see if I could help a bit.

Sharkbite fittings are good for repairs and for some transitions but I would not rely on them for whole house transitioning... otherwise sweating/soldering is best overal.l

It is not hard to solder... just takes a little practice.. glad to talk you through the basics if you want.

In fact, if you will be stubbing pex pipe into a room you will most likely want to transition over to copper pipe before stubbing into room so you can use the more traditional fittings/shutoffs available at home depot, etc... AND you won't have to stress the tubing trying to bend it to 90 degrees (inside wall this can be hard with pex.. so we transition over to copper then use copper 90 to stub into room) and you will have something rigid to attach a clip/hanger too.

PEX piping must not go any closer than 18-24" near any appliance that heats water... this means water heater and boiler. You will need to transition using copper fittings here as well.

Check out this link for a little more info. On PEX systems:

AOL Search

Also, I would not insulate the pex pipe in the attic... Instead, I would have you run the pipe so it is as close to ceiling as possible... then you will install at least 12-24" of batt insulation over the pipes. There must be no insulation between ceiling and pipe... ok? The idea is to create an insulation gradient such that the pipe is on the warm side of insulation (ceiling side) and always protected from freezing. Let me know if have questions on this...

So, let me know what you think here... I'm glad to help more if I can.

MARK

[Stubits]

Mark-

This is EXCELLENT! Thanks so much. I think I will learn how to sweat joints, probably not a bad skill to have in general.

The advice of transitioning to copper at the stub outs is well taken. I will definitely plan on doing so, thanks!

Also, thanks for mentioning the hot water heater. I will make sure to do so.

On the insulation... thanks! This is great information and not a problem at all, as the attic is entirely uninsulated and I will be doing the insulation at the same time. I guess I will run the PEX first and then do the insulation. Now, could I insulate the PEX as well, to avoid the hot line from sweating? Or totally unnecessary?

So, not sure if you saw my earlier question about sizing, does it sound right, 1" from the main, 3/2" branches and 1/2" to the fixtures?

What are your thoughts on how often I should connect/attach the Pex.

Finally, at least this time around, do you see any trouble running PEX in the AC/Heat chase? That is to say, can I run the PEX in proximity to our AC/forced air heat ducts?

Thanks!

[massplumber2008]

Hello...

If you were to insulate anything it would be the COLD water pipe as it is the cold water pipes that sweat in certain conditions... not hot water.

It cannot hurt to insulate the cold water if you think sweating could be issue.

I would not insulate the hot water as it is hot water that always freezes before cold water does and I want your hot water pipe to pick up as much heat from the room (through ceiling) as possible... just be sure to cover pipe as discussed earlier (run pex first... like you said).

Running pex system--------------------------------------------------------------------------------------------

Run 1" main and then run 3/4" pex to all fixtures (hot and cold) except the toilet... toilet can be 1/2" pex.

1/2" pex is really closer to 3/8" copper tubing as it reduces to 3/8" at all fittings... 3/4" pex is really closer to 1/2" copper tubing again, because fittings are reduced below 3/4"... so for best VOLUME for showers, etc... run 3/4". Not that 1/2" won't work.. it will... just will have a slightly smaller volume available when others use other fixtures in house.

Pex is so easy to work with I say you hang it using your own common sense. Code tells me I need to clip/hang every 6 feet or so... in my area. As Steve62 said, just don't clip/hang too stiff... allow for expansion/contraction.

I don't see any problem running these pipes in AC/HEAT chase at all... just keep pipes maximum distance from duct work and you should be fine.

SOLDERING---------------------------------------------------------------------------------------------------------

Bob already took you through basic steps... I just wanted to list it all out for you...

1) Drain pipes of water... drain to lowest fixture in home and open all faucets in house (including outside faucet)

2) Take plumber's sandcloth and clean copper tubing about an inch on end of pipe... clean very well.

3) Take cleaning brush and clean fitting(s)

4) Flux the inside of the fitting (both sides if elbow fitting or if tee fitting all three sides of tee) and flux the pipe end (about 3/4") with a flux brush and self-cleaning flux.

5) Connect fitting and pipe end together. Do not solder just one side of a fitting unless you have a pipe in the other side of fitting.. will burn other side.

6) Apply heat to fitting so the heat is drawing the solder into the fitting. Here, you will see that bubbles begin to form at the fitting... as bubbles decrease it will be time to apply LEAD-FREE SOLDER. ALWAYS apply solder to the bottom of the fitting first..then apply solder to the top of fitting.

The blue part of the flame should be about 1/4" or so from the fitting... the idea here is to heat the fitting and then draw the solder into the joint not by melting solder with flame but by heating the joint so it actually sucks up into fitting (why flame needs to be behind fitting drawing solder in).

After you have soldered joint can give it a quick, light wipe with rag if you want.

Always be sure to wear GOGGLES when soldering... especially in the beginning and when soldering where dripping solder can BOUNCE of surface and up into your face.

Practice on a few fittings first. One big trick to fitting copper tubing and soldering is to CRIMP the fitting onto the pipe using a pair of pliers... but note here that I am talking about a little crimp and then a 1/4 turn or so to lock the fitting in place...

You can also check out these websites for a video on soldering:

http://www.askthebuilder.com/How_to_...pe_Video.shtml

http://www.schooltube.com/video/9770...er-Pipe-Module

Both these guys show one side of fitting being soldered... don't do that as discussed above.

MAPPGAS (available at home depot) is best torch for homeowners... burns hot.

Also, be sure to have a FIRE EXTINGUISHER handy... just in case!

Always solder any threaded fitting first.. let cool, then apply pipe dope or teflon tape if needed (male fittings) and THEN can install and tighten using wrench/pliers.

And finally, wash the pipes after you solder them... I use baking soda and water to break down any acidic residue left from the flux!!

Let me know if/when more questions...

MARK

[Stubits]

Mark-

This sounds fantastic.

Frankly, I was set on hiring a plumber to come in repipe, but after hanging out on here for a while I am confident I can pull this off myself. Although PEX is completely up to code here, I only found one plumber who would run it and he said that the cost of PEX and copper repipe would be the same... sounds a bit off to me given the huge cost difference in materials.

Thanks for explaining the insulation issue. I think I will avoid insulating the pipes all together, not sure if sweating would be an issue here. I will make sure to run all the pipes under the insulation.

I had no idea about the relative sizes of PEX, thanks for clarifying that; we've been living with suboptimal water pressure for months now (we just moved in), I don't want to have the same problems now.

What distance should I keep the pipes from the ductwork? The chase isn't huge, so there isn't lots of extra room. What would be the minimum?

Can you just gut check this setup for me? I can include pictures or a diagram if it will help.

At present, we effectively have two major branches, one that feeds our basement bathroom/kitchenette/laundry room/primary kitchen and the other that feeds our upstairs bathroom. The basement bathroom/kitchenette/laundry room/primary kitchen are all done and interconnected in copper, but fed off galvanized steel, I know where the main connection point is.

In the repiping, I will have 1" coming from the main to our utility closet where it will tie into our hot water heater. Additionally, there will be a 3/4" supply line running off the 1" main to the upstairs bath (via the attic) and a second 3/4" supply line running off that 1" main to the basement bathroom/kitchenette/laundry room/primary kitchen. Similarly, out of the hot water heater I'll run a 3/4" supply line to both of those locations.

Given that it is a repiping, I am not planning on using a manifold/home run system. Will this work? Will we still have good water pressure throughout? Is there anything I can/should do differently?

[ballengerb1]

Stubuts, we never mentioned this but have you checlked the permit requirements in your area?

[Stubits]

Ballenger:

Each of the plumbers I brought in, reputable, licensed, bonded and insured, indicated that they would not suggest getting a license for this work. I have confirmed that PEX is allowable under code.

[ballengerb1]

I think you meant permit, not license. You can call the building department and ask that question without telling them who you are. I'm gun shy of doing work without a permit when I am fairly certain one is required.

[massplumber2008]

Stubits... just maintain max. distance you can in chase and you will be fine... keep pipes from touching duct work.

I posted some soldering sites at my last post so check them out... also added more info. As you were typing your post so be sure to reread my last post... ok?

Otherwise, all sounded fine to me... ;)

Good luck!