Plumbing for sink and toilet

Old 07-14-18, 05:53 PM
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Plumbing for sink and toilet

Adding a toilet and sink to a basement. Directly overhead is the supply line.

When I run a branch from the cold water line to the sink and toilet can this be one run of this main then "t off" of this run to the toilet and sink or do I need a run for each from the main?

If I can run 1 line and "t" would it be the same size piping for the new branch and then for both sides of the "t" or would the branch be larger and then the run the sink and toilet reduced?

Also sizes would be great.
Thank for the help.

Sorry for this question and those who say to "Google it" as it is pretty basic to those who plumb. I just want to do it right.
Old 07-15-18, 05:43 AM
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You can T off the main line then T off the new lateral for the toilet and sink. Since it's only a toilet and sink you could make your new lateral line and your T'd lines 1/2". Better would be to make your new lateral 3/4" but it's not required.
Old 07-16-18, 11:09 AM
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Both the sink and toilet have 3/8" supply lines, so keeping a single 1/2 feed to the both of them (and a shower if needed) is typical.

If the run is feeding multiple rooms (bath/kitchen for example), then upsizing to a 3/4" lateral is a good idea.

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