Home>Discussions>BATHROOMS>Installing 2nd Floor Bathroom
5 posts / 0 new
Last post
schanz
Installing 2nd Floor Bathroom

I'm working on a turn of the century foursquare style house. I want to put a bathroom in a room directly above the room where the existing bathroom is located downstairs. There's even a 4" pipe running up through the room and out the ceiling. I'm assuming that this is the air vent on the sewer line in the bathroom directly below. If confirmed, I also assume I can tee into this from my new upstairs toilet. I also want to add a shower and vanity.

I can line the toilet up with the existing pipe so I'm between the same floor joists but for the shower and vanity, I was planning on drilling 2.5" holes through the floor joists and meet up with the toilet drain.

Can you shoot holes in this plan?

This room is a total demolish and remodel so it won't be a big issue pulling up the tongue and groove. I'd like to keep it if I could but it's not mandatory.

Shaun
Re: Installing 2nd Floor Bathroom

The 4" is probably venting every fixture from the 1st floor so if you ty a bathroom off of that and dump water in it it will no longer be a vent. It will be a drain for the second floor and the first floor will no longer be correctly vented. You would need to get a 3" line from basement, run your second floor bath, then tie that 3" back into the 4", six inches above the height of the vanity.

schanz
Re: Installing 2nd Floor Bathroom

Sounds easy enough. I saw a diagram in a plumbing book that showed both floors draining in the same pipe that went out the roof so it got me wondering.

I'm also partitiong the downstairs room into two bathrooms so I'm hoping the one vent suffices given the proximaty.

Shaun
Re: Installing 2nd Floor Bathroom

Yes you could have both floors draining into the same pipe if the fixtures below the second floor were separately vented and tied back in 6" above the highest fixture on the second floor. Mass code wants a vent within 5' from the trap on an 1-1/2" line, 6' for a 2" line, 8'for 3" and 10' for 4". The pitch between vent and fixture must be 1/4" per foot no more no less. If you get your hands on a do it yourself book it should have diagrams to give you an idea.

schanz
Re: Installing 2nd Floor Bathroom

I can certainly do that.

FYI. Here's the diagram I was referring to from the book: Ortho's All About Basements, Attics and Bonus Rooms. I think my wife brought it home from the library.

Sponsored Stories

TV Listings

Find TV listings for This Old House and Ask This Old House in your area.