Plumbing vs. underbelly

[its a ritz-craft]

I own a Ritz-Craft modular. Apparently the hot water plumbing was routed in one long string. It takes forever to get hot water to the kitchen sink and the water heater is only twenty pipe-feet or so away. I believe it's the next to last device on the line before the dishwasher. In addition to the annoyance of waiting, it's very wasteful.

I want to make some changes to the plumbing to the effect that the various fixtures will be grouped together on their own lines. For instance, the kitchen sink and the dishwasher fed direct from the water heater. Likewise for the shower and sink in the second bath.

The home is plumbed with PEX. I haven't worked with this but I have worked with Qest. For that I had to buy expensive fittings to make changes. I've also worked with copper and am a decent solderer. I am assuming that Shark Bite fittings would be the way to go for this but I'm open to alternatives.

All that said, the most daunting thing about doing this work is the underbelly. All the pipe is routed behind the underbelly sheet and underfloor insulation. Since I can't know exactly where the piping is without exposing what may be a sizeable amount of the undercarriage, I'm wondering how I might handle taking down, potentially, a lot of the underbelly and successfully and neatly replacing it. I watched the YT video by the guy who patched a hole in the underbelly plastic but I think I'm looking at a much bigger project here.

I also have some concern about taking down a rather large piece of sheeting and replacing it alone. Do I need help? Special tools?

I've attached my guess at the current plumbing.

Thanks for any advice/assistance offered

[JD]

Seems to me just adding a Tee to go direct to the kitchen and capping off the plumbing after the GB sink would get your best hot water. I have included a your drawing showing the red as the new line. All of the gray would be 3/4"

To locate and cut the belly only where the pipe is, just follow the pipe. come in at the WH a bathroom or kitchen. You can also just cut an easily repairable slit and reach up to feel the pipe. Open up belly areas like you are making access doors. Always cut it to where it is easy to repair and not blocking any light you might have.

I have been using PEx with the stainless steel clamps for many years and have yet to have a failure that was the fault of the clamp (vs copper ring). I also only need one tool, it is cheaper, smaller easy one hand operation, fits in small spaces. Using PEx with Stainless, buying the tool is cheaper than using PEx and Sharkbite.

[JD]

Here is the tool I use. Made by Apollo. I bought mine at Lowe's but you can get them at many stores and online.

[Greg]

JD is 100% right stay with PEX. easy to work with when you have the tools.

Greg

[its a ritz-craft]

Seems to me just adding a Tee to go direct to the kitchen and capping off the plumbing after the GB sink would get your best hot water. I have included a your drawing showing the red as the new line. All of the gray would be 3/4"

That's great! I was over complicating things. Your suggestion would eliminate a lot of aggravation. I 'assume' I'd be able to push a new piece of PEX through to the sink under the floor once I penetrate the vapor barrier and insulation. I can see the need for at least three penetrations so I guess I'll be getting a patch kit. This work won't be done right away, it is February after all.

Open up belly areas like you are making access doors. Always cut it to where it is easy to repair and not blocking any light you might have.

I get the access door reference but never having done this work, I'm not clear on what you mean by 'where it is easy to repair'. Does this mean easy to maneuver and get to or picking a good location in the barrier to cut? With no light it's pretty dark down there, house sits on a foundation. One of the best purchases I've made in recent times is a headlamp. http://www.amazon.com/Fenix-HP05-batter ... B00HPM1D84

Using PEx with Stainless, buying the tool is cheaper than using PEx and Sharkbite.

I've priced Sharkbite fittings. You're right, they're not cheap. Is the tool pictured crimp only or does it also cut?

[its a ritz-craft]

JD is 100% right stay with PEX. easy to work with when you have the tools.

Greg

I fully intend to stay with PEX. The other materials were mentioned only to illustrate that I do have some experience with basic plumbing stuff. Thanks!

[Greg]

Pex is easy to cut, you can almost use pruning shears. Make sure the cuts are square.

There are a few ways to repair the belly after you cut it. JD has a method that works well for him, or you can buy belly tape that you warm up after you apply it. Mark has it in the site's store.

Greg

[HouseMedic]

You can use just about anything to cut Pex with but I like this type of cutter. Also work great on CPVC, PVC, Rubber Hose and more.

Ron

[its a ritz-craft]

You can use just about anything to cut Pex with...

I see Ridgid has a PEX cutter http://www.walmart.com/ip/RIDGID-151P-3 ... 4/41218698 which looks much like the one I have for cutting copper. Will the one I already have do just as well as the knife type?

Also, does anyone have an opinion on brass vs. plastic/poly PEX fittings?

[Greg]

Brass!!!

[1987Commodore]

Even a utility knife will cut it. It depends on how long you want to take to make each cut. I'd say go ahead and try your tubing cutter first. I say brass fittings also.

[its a ritz-craft]

Brass fittings would be my inclination. I see the plastic is less costly but the main issue, for me, is not having to down there again to fix a worse problem caused by a burst fitting. Plastic just doesn't inspire confidence.

I do appreciate all the replies. I feel confident enough now that I can start a list for materials and tools.

Something else has occurred to me. Before I can start replacing fittings and reconfiguring lines I'll have to drain the line. I suspect this may be necessary at more than one point. Since all this work will be done on lines located above the insulation the water remaining in the line will, of course, fall into the insulation - and probably my face! Any suggestions how to handle this?

[Greg]

Plastic is more prone to problems. As long as you are doing the job it is a perfect time to add shut off valves. If you do add shutoff valves, again buy quality valves. Either Brass or Stainless, they tend to resist corrosion. Use either a Gate or Ball (1/4 turn) valve, they allow a full flow and are reliable when you need them. The last thing you want is a valve that does not stop a flow when you have a leak.

Greg

[its a ritz-craft]

As long as you are doing the job it is a perfect time to add shut off valves.

There are shutoffs now in the lines to each fixture. They're not the full size industrial ball valve in that the handle's on the small side but they are only a ninety degree turn. Is this what you mean or are you talking additional valves to isolate sections of the system?

[Greg]

Someone must have added them, usually the only valve is the main shutoff.

Greg