Hello folks, I have a bit of a dilemma I'd like your wise counsel on. I'm putting a small 3/4 bath on my second floor, which is actually a large converted attic. The floor up there is framed with 2x6 joists. From what I've read so far, that's not enough vertical room to hide the shower P-trap or the toilet drain. On top of that, the maximum notch OD (Seattle code) is 1/3 the joist depth, so basically the shower and toilet would both have to be in the same bay as the waste stack, which just isn't a feasible configuration.
I really don't want to drop the ceiling below, because there's just no way to do it without looking awkward. I could sister 2x10s to the joists to give myself enough depth to notch for the drains, but I would lose so much ceiling height that it would make much of the upstairs unusable.
The solution I currently investigating is a macerating toilet. They're expensive, but I've found units that accept inlets from the sink and shower drain, and have an outlet diameter of 3/4". Best of all they don't need gravity, so they don't directly require any plumbing in the floor! The outlet could just disappear into the wall and then run 6' over to the waste stack. However, I assume the shower would have to be significantly raised so the drain could flow into the macerator unit? Or are there inline pumps that work for shower drains?
To address structural integrity concerns: this bathroom with be right above the downstairs hallway, so that the two walls of the bathroom that run perpendicular to the floor joists will be immediately above the downstairs hallway walls. The span is only 5 1/2 ft, and the joists are on 16" centers. It is very sturdy in that spot, as long as I don't go boring through joists.
That said, I do intend to keep the weight down as much as possible (linoleum instead of tile, etc.). I should also mention that this bathroom will only be semi-permanent. In the next 5-7 years we will do a major renovation and everything upstairs will be completely redone.
I've never dealt with anything like this before so whatever intel you're willing to share is much appreciated. Basically, though, my 3 main questions are:
I really don't want to drop the ceiling below, because there's just no way to do it without looking awkward. I could sister 2x10s to the joists to give myself enough depth to notch for the drains, but I would lose so much ceiling height that it would make much of the upstairs unusable.
The solution I currently investigating is a macerating toilet. They're expensive, but I've found units that accept inlets from the sink and shower drain, and have an outlet diameter of 3/4". Best of all they don't need gravity, so they don't directly require any plumbing in the floor! The outlet could just disappear into the wall and then run 6' over to the waste stack. However, I assume the shower would have to be significantly raised so the drain could flow into the macerator unit? Or are there inline pumps that work for shower drains?
To address structural integrity concerns: this bathroom with be right above the downstairs hallway, so that the two walls of the bathroom that run perpendicular to the floor joists will be immediately above the downstairs hallway walls. The span is only 5 1/2 ft, and the joists are on 16" centers. It is very sturdy in that spot, as long as I don't go boring through joists.
That said, I do intend to keep the weight down as much as possible (linoleum instead of tile, etc.). I should also mention that this bathroom will only be semi-permanent. In the next 5-7 years we will do a major renovation and everything upstairs will be completely redone.
I've never dealt with anything like this before so whatever intel you're willing to share is much appreciated. Basically, though, my 3 main questions are:
- Is the macerating toilet idea a realistic solution?
- How high do I have to raise my shower if I assume the shower drain meets the macerator tank 1" from the floor?
- Are there drawbacks or other variables I need to be aware of?
