size of supply lies for new bathroom

gwilkrrs

i am building an addition with a full bathroom. i am bringing the hot and cold supply lines to it with 3/4" lines. i plan to transition down to 1/2" lines right at each individual fixture. is this ok or should i step down to 1/2" as i come off the main lines and run the individual supplies in 1/2"?

joecaption

1/2" off of the main line.

gwilkrrs

ok- i was wondering because off the main lines i will run about 16'-20' to each fixture and didnt know if the 3/4" would hold more water for those distances.....

techpappy

3/4 lines allow over twice the volume of 1/2 inch however, unless your water pressure is very low the 16 -20 foot 1/2 inch lines should handle the flow easily. UNLESS..you ARE INSTALLING SOMETHING LIKE A SUPER SHOWER WITH 6 HEADS!!then 3/4 might be required.

gwilkrrs

nothing fancy in there- double vanity, ttoilet and standard shower. just dont want to goof this up and wish i had more

techpappy

I n my last house where I acted as General Contractor I was on a well and had 3/4 mains in basement with 1/2 inch to fixtures including MB ensuite on second floor which was farthest from pressure tank (65') with no problems. When we sold, the home inspector ran the tub, shower and sink full blast then flushed the toilet with no discernible drop in flow and gave it the ol'

DidIDoThat

Just run 3/4" to the bathroom then 1/2" to the fixtures.
The cost difference is minimal for a job this size.