Pex, vinyl tubing or???

[aa1bflyboy]

I’m replumbing an Aloha 32. Presently she has the 30+ year old gray plastic that I’m told is the precursor to pex. It has been suggested to use the reinforced vinyl hose as it is flexible and therefore reduces the need for fittings and a specialized tool for installation. IE: clamping/crimping tool & cutter. I’ve been pricing pex pipe and fittings vs the vinyl and seeing the cost of pex to be less and seems to me would be a better job. Pex is quite flexible and I don’t see any drawbacks other than maybe the clamping/crimping tool cost and it use in tight areas.
Your comments are appreciated, thanks in advance.

[rbk]

Pex is not that flexible and the fittings are still prone to failure, maybe more so in a marine environment. Although that wouldn’t put me off from using it. Both have their pros and cons.

[Tellie]

Pex is being used on many new boats today. Most of which use the quick Shark bite type fittings. I don't see much of the crimped fittings anymore.

[Wotname]

Originally Posted by aa1bflyboy

....... It has been suggested to use the reinforced vinyl hose as it is flexible and therefore reduces the need for fittings and a specialized tool for installation. ........

Your comments are appreciated, thanks in advance.

If you use reinforced vinyl hose, make sure it is food safe vinyl otherwise you will get tired of vinyl flavoured water.

[nightowle]

Go with Pex and the Shark Bite fittings. Long term you'll be glad you did.

[Freedom45]

Pex, no barbs or worm clamps...
Have never had any problems with pex, easy to assemble and disassemble without tools.
No leaks.

[Jammer]

I have used both


PEX tubing itself will last longer than the rest of the boat and will not leak or leach chemicals into the water. The fittings can be a weak point particularly if stressed or subject to motion. Sharkbite fittings are larger and more expensive and sometimes leak. In theory they are reusable. Crimp fittings require tools and more space to work, in tight spots you have to plan ahead and pre-assemble portions. They are a one-way trip so you carry spares.


Vinyl is much more flexible, easier to cut, fittings are reusable. There is some cold flow so that you have to retighten the clamps periodically. It will become brittle and require replacement after a number of years. It is generally quieter as it is soft enough that it won't rattle against things, and it will absorb some of the impulses from a pump. Due to its flexibility it puts less stress on connections.

[sailormed]

Go with Pex. The only tool you need is a good cutter to get clean cuts. You can find these for a couple of dollars. Make a mark on the tube for the depth to insert so you are sure full depth is attained. They only go loose when not inserted correctly. Buy the fittings with metal retaining clips.

[Pitchondesign]

My boat is 30 years old. I have a combination of pex with shark bite fittings and reinforced vinyl. The pex tubing is better than vinyl, but good embossed hose clamps are far better than shark bite over the long term. I have had no pex tubing leaks, and one reinforced vinyl leak at a bend where it split. I have had mulitple shark bite leaks. The share bite leaks are all the same, a failure of the o ring. If I had to do it again, I would use reinforced vinyl with good hose clamps. The vinyl bend radius is tighter than pex, hose clamps are less expensive than Shark bite fittings, the overall system reliability is better with vinyl, and its easier to find parts in remote locations.

[lvictorlucas]

I use Tygon for a lot of applications. More expensive but a good general compromise.

[SV Bacchus]

My 04 boat has Pex and zero leaks. Fittings are Sharkbite style and a couple of places, for access to other things, I have taken the line out and then reinserted when ready. Still no leaks.

Pex is susceptible to UV damage so don’t use it anywhere there is direct sunlight. Inside cabinets and lockers is fine as they are usually not open that long.

[roland stockham]

Pex is easy to use, convention in buildings is that it is fine in accessible area but not behind walls unless protected by a stop tap i.e. from a stop tap behind the wet wall to shower fittings is fine but not for main distribution. This is probably just caution and plumbers still seeing as 'new tech'. Crimp fitting tools are easy to use and about $35, the angle head ones are pretty good at getting into tight spaces.

I like shark-bite, refitted my boat with it 10yrs ago and it has been problem free. I used plastic fitting which where available in the UK but when I looked at getting some in Canada they seem not to be available. The brass once are much more expensive and would concern me on a boat as it is not marine grade and could have issues especially in a bilge area. Crimps have the same issue with the brass but are much cheaper and simpler if they do need replacing. That would swing me towards crimps if doing it here and not able to get plastic sharkbites.

[mvmojo]

Originally Posted by nightowle

Go with Pex and the Shark Bite fittings. Long term you'll be glad you did.

This ^^^^. The difference in cost is nickels and dimes in a five dollar world. I have all CPVC piping and it's worked fine for years but if re-plumbing, PEX and Shark Bite would be an easier job.

[Niall leslie]

- I would vote for sex for a number of reasons including that it can be easily heat formed if desirable.
- For fittings the crimp type onto plastic fittings are generally excellent for salt water use and where these fittings are inappropriate then I've found that Sea Tech are by far the best. They are similar to Shark Bite but all plastic with SS grippers, safety locks are available and they are easily released if required.
- I've been using them for over 6 years with literally no problems.
- To avoid pump pressure pulse noise issues and to avoid the pump always having to operate for small quantities of water I use a pressure tank in the system of total capacity about 4 litres.
Cheers,
Niall.

[Tetepare]

If your boat is spacious enough with no tight bends, use Pex. No way I could do all mine with pex, too many sharp bends. I don’t trust sharkbite, too many horror stories. That said, I redid the whole house with pex and even with the small tool sometimes it was tough to get the fittings on due to space constraints.