Fresh Water Hose Size

[Windblown]

I'm getting ready to install a new fresh water system in my Formosa 41, and intend to replace everything. I'm planning on installing 5/8 inch hose throughout. Is there any reason I should consider a different size? My old Catalina 30 has 5/8ths, and it seems to work fine. I have 1 head with a shower, plus the galley of course. I will eventually be putting in a water heater. The hose runs look fairly easy, and won't be long. Cost isn't really a factor, the boat is our home, and we expect to liveaboard long term. I want to do it right the first time, rather than try to save a few pennies, and then have to do it over in a year because something isn't quite right.

Thoughts?

[sestina]

I replumbed my boat and used 0.5" (15mm) Hep2o. This is in the UK and pipe sizes are "nominal". Hep20 is a plastic pipework system, used for everything from underfloor heating systems to hot and cold drinking water. it comes in 3m lengths or 25m coils.

It is important to use opaque pipework. If you use the cheap clear plastic hose, bugs and bacteria love the light and will multiply accordingly... You'll forever be disinfecting the system whilst drinking coffee that tastes of swimming pool. Keep it dark, fit a good filter and you'll never have to lug bottled water again.

[GordMay]

Originally Posted by sestina

I replumbed my boat and used 0.5" (15mm) Hep2o. This is in the UK ...
... It is important to use opaque pipework. If you use the cheap clear plastic hose, bugs and bacteria love the light and will multiply accordingly...

I’m not specifically familiar with the Hep20 product, but cannot recommend Polybutylene plumbing.
Hep20 is a is a thermoplastic Polyolefin, called Polybutylene. Although still widely used in Europe and Asia, the suitability of polybutylene for use in plumbing is controversial.
Polybutylene plumbing was used in 6 to 10 million homes built in the United States from 1970 to the mid-1990s. Problems with leaks led to a class action lawsuit, Cox vs. Shell Oil, that was settled for one billion dollars.
The material oxidised when used in hot water systems, developing longitudinal cracks which eventually punctured the walls leading to floods and damage to properties. Many acetal resin fittings also cracked, a problem caused by chlorine attack.

➥ The Problems with Polybutylene - Pacific Crest Inspections located in Anacortes offers home inspections in Skagit, Snohomish, Whatcom and Island Counties

➥ Leaks Plague Polybutylene Plumbing

[RaptorDance]

If I had to re-plumb either my boat or house, I would consider PEX tubing and fixtures. Has anyone used PEX on their boat?

[Windblown]

I was planning on using Shields polyester reinforced hose, just wasn't sure if I should use something other than 5/8ths. This is what I have on my old boat, it's original (1978) and I have yet to have a hose spring a leak.

[Pblais]

I would consider PEX tubing and fixtures. Has anyone used PEX on their boat?

Ours is mostly all PEX. It was built that way in 1991 and it's never had a problem related to the use of PEX. We don't have much of it and all the runs are very short. There is no water forward of a point 3 feet forward of the companion way. All the plumbing runs on either side of the head on the forward and aft bulkheads. It beats hose clamps.

[Bash]

my boat is all 15mm tubing. I don't see what the advantage would be of anything thicker.

[Cheechako]

There is no need to use 5/8's. 1/2 is fine and may be easier to get the appropriate fittings for various appliances faucets etc. The larger the tube the less resistant to pressure it is without increasing wall thickness... (not sure this is an issue or what the psi rating of the shields is hot), also with 1/2 you can use the small style hose clamps, not sure if you can with the 5/8 or not... Your faucet water velocity may be better with 1/2 also...

[Ishmael]

My boating experience is limited, but I am a plumber. 1/2" is what we commonly use to plumb a typical bathroom in a house: 1 tub/shower, 1 or 2 lavs, and a toilet. 1/2" PEX tubing would be great in a boat - very easy to work with.