Why would the plumber/builder do this...

[Sean the Nailer]

By code you can only run 2 fixtures on a half inch line, 3 fixtures on a 3/4" line.

That's interesting. You must live in some place that is 'modern' and based upon logic, physics, reality, and progress.

Every single home/house I've lived in here in Canada, and ESPECIALLY any/all those in Manitoba, have been plumbed for 1/2". As in, they all had either 5/8" or 3/4" supply line, coming in through the basement floor. Then through the meter. Then after the meter, they are ALL necked down to 1/2" tubing. And THAT is what is run to every single fixture, toilet, tub, faucet, vanity, dishwasher,,,,, EVERYTHING.

Only 1 house I am aware of, the owner himself changed out the plumbing supply line to the hot-water tank back to the original 5/8", and after doing that, there was never an issue with anyone flushing a toilet or running a tap while anyone was in the shower.

There was a massive 'conserve water' thing that happened here in the 70's, and everything had those 'reducers' on the faucets and the showerheads and such.

One landlord I had years ago, stated "you couldn't SUCK the water out of that showerhead fast enough to wash your hair"..... hilarious.

So yeah, I appreciate that space-age village that you're living in, Mister Jetson!

 

[Im2bent]

 

[Aftermath]

I don't know about your locale, but here the house insurance REQUIRES metal-braided hoses connecting the toilet and clothes washer to the supply. Too many homes have had 'flooding' claims because of plastic lines breaking/freezing/failing.

So, that makes me ask, how 'confident' are you?

I always install one of the fail-safe type check valves that will prevent that from happening.

 

[Whiskey Tango Foxtrot]

We need a dumbass construction sticky- post stupid stuff you’ve seen on site. It’d be legendary.

Found this on my house build 15 yrs ago. 3/4 pvc

 

[Lawless]

I found the exact same situation in a house belonging to a customer. He had squishy squish sounds under his kitchen hardwood. Turns out an installer had failed to use clips on the Pex and it was resting against the drywall. A drywall screw missed the stud and went right into the line.

It took 4 years to rust out and leak.

Not doing shoddy work makes everyone’s life better down the road.

On Pex, it is proven.

 

[jg6.5]

By code you can only run 2 fixtures on a half inch line, 3 fixtures on a 3/4" line.

As others have said, this isn't entirely accurate.

Not sure what the code says where you're at, but IPC 603.1 says "The water service pipe shall be sized to supply water to the structure in the quantities and at the pressures required in this code. The water service pipe shall be not less than 3/4 inch (19.1 mm) in diameter."

That's for the entire structure. It's very common, at least where I live, for single family homes to be fed with 3/4" from the street to the water heater, then hit everything else in the structure with 1/2" looped under the slab daisy chain style.

Minimum fixture supply sizes are then shown on table 604.5

Again, this is just code as adopted where I live - it may be different in your neck of the woods.

 

[jg6.5]

I don't know about your locale, but here the house insurance REQUIRES metal-braided hoses connecting the toilet and clothes washer to the supply. Too many homes have had 'flooding' claims because of plastic lines breaking/freezing/failing.

So, that makes me ask, how 'confident' are you?

I find this interesting - what does the insurance company think is inside the braided SS shell of those supply lines?

 

[mahlv]

It's been 1/2" supply to 3 fixtures or bathroom group here for the short 20 years I've been plumbing here