# OF FIXTURES ON 1/2\" WATER LINE?

LARRY_2

FIRST OF ALL IAM NOT A PLUMBER,BUT IAM AN ELECTRICIAN.
IAM BUYING A NEW HOME AND I WAS WONDERING IF ANYONE KNEW IF THERE IS ANYTHING IN THE 2000 UNIFORM PLUMBING CODE THAT STATES THE NUMBER OF FIXTURES ON A 1/2" WATER LINE? I HAVE NOTICED THAT THE PLUMBER PUT THE WHOLE MASTER BATH ON ONE RUN. THAT IS ONE DBL. VANITY(TWO SINKS), THE WHIRPOOL TUB, THE SHOWER AND THE STOOL. IT HAS PAST INSPECTION. MAYBE THIS IS ALL TO CODE,BUT IT MAKES ME WONDER. ANY INFO WOULD BE GREAT! THANKS.

Mike T., Swampeast MO

If UPC anything like National...

...everything gets a bit vague when it comes to sizing water distribution residentially. Typical water pressure, elevation of the fixture above the main, pipe material, and size/length of meter/entrance all come to play. This makes it impossible to suggest ANYTHING as "one size fits all."

If you think this sounds a lot like choosing the proper size wire for a service or large appliance, you're right. BUT, electrical has a big (about 2x I believe) safety factor built in. Since you don't stand a chance of burning down the house by overloading the plumbing, there is no such safety factor for pipes. If electrical systems were designed for the same rate of simultaneous use as most plumbing systems, TV pictures would shrink to about half size when the A/C kicks in.

I'm assuming this is a speculative home (built without a specific buyer) and the sizing you mention is pretty typical. 5/8" meter; 3/4" mains; 1/2" branches off the mains serving fixture groups. If you're lucky you get a 1" entrance main, but it's often only 3/4".

For an average 2 1/2 bath home, this is generally adequate as long as the static pressure is at least 50 pounds. You'll have the typical problems during periods of high water use.

If this bath is above the ground floor and/or it's a whirlpool larger than a standard tub, look out. Unless static pressure is quite high you're likely in for performance problems. Five would get me twenty that the hot water heater is also undersized if this is the case.

Larger whirlpool tubs really need 3/4" valves, 3/4" branches, 1" mains and 3/4" meter--minimum--plus either large/multiple hot water tank(s) or a generously sized boiler-operated heater. The "real" cost of a properly-installed "garden" tub is easily 7-10 times the cost of the tub itself--much more in fancy tile installations.

Speculative builders are driven by a market wanting more and more "frills" all the while keeping the cost below their competitors. As a result, mechanicals are often the easiest place to shave cost. Pity.

When I sized my own domestic system, I found that I really needed a 1" meter. When I ordered the change from the city I was told, "you'll have the only 1" residential meter in the city (35,000)--there's an OCCASIONAL 3/4" meter in new homes with 6+ baths." They really freaked when I ordered two 1" meters--one for domestic, one for irrigation. Mine is a big house, but most definitely no mansion.

I just love watching people install in-ground irrigation with a 5/8" meter and half an acre or so to water. Such lawns become utter slaves to irrigation as they are extremely shallow rooted and utterly drought intolerant. Truly wasteful of precious water.

p.s. ALL CAPS are hard to read and it's considered "shouting" in internet lingo.

Mark J Strawcutter

water service

I live in what is now the middle of town. Two doors down is the first house built in the area. Mr Henry was in his mid-90's when he died. Was born and lived his entire life in that same house.

The folks that purchased it from his estate were surprised to find that he paid the tap-in fee many years ago when "city water" came thru but never actually connected. Continued to use the dug well located right outside his back door.

Mark

canuckDale

Must be the same as Canada?

I mean, it runs downhill here too and weighs the same?

My National Code says you have 9 fixture units there. Pressure decides the size. Minimum 28 psi - 6 FUs, min 43 psi - 9FUs, min 56 psi 11 FUs. ( City codes determine minimum service pressures ). All with a maximum total developed length of 12 meters/ 40 feet.

But I agree with Mark. Bigger is better and quieter too!!!

Jackchips

All water

can be sized by the amount of static pressure available, the length of run to the furthest fixture with the greatest demand, the feet per second you want the water running through the pipe and the pressure lose available. ASPE (American Society of Plumbing Engineers) puts out the sequence that should be followed to determine the proper sizing. It's true one size does not fit all and proper engineering is required even in residential buildings to assure flow and "speed of the water" through the pipes to ensure quiet and proper operation so that the pipes will provide the necessary water and not deteriorate from the inside. In many instances the building supply and the meter can be smaller that the piping required for the building depending on the available static and residual pressure. In no case would 1/2" be large enough for the amount of fixtures listed.