Caryncbreeef
Member
So After much effort designing the dwv system for my total remodel we got the parts and got started (thanks to a few of you for your excellent advise). I did a lot of studying and reading both the code and guidebooks from IPC and am feeling more comfortable in understanding what is code and why.
first question is about pipe fall. I understand what fall is required, and set up a level with a block so im not guessing. Question is this : for example on the main 3” drain, if a 3” combo is installed plumb and square to the drain line, will it have correct fall for the branch or does it need a little turn and test it with a 2’ length of pipe ? I read that the dwv fittings have the correct “Fall” built in to the fitting, but havent been able to tru verify this. We are measuring and double checking before gluing but it would be good to know.
one other fall question. On a run of 2” connecting a lavatory and bidet to main the drain, A section of 2” pipe connecting the wye from bidet to 233 combo at the main drain (about 18” long piece of 2”) the fall is slightly less than the 4’ section on the other side of the wye back to the lavatory. With hangers we got the fall looking good, without requirements. How exact does the fall need to be to work properly? are there acceptable tolerances or does it need to be dead on?
2nd. When installing toilet flanges, finished floor for both will be approximately 11/2” above subfloor (tile, durock, membrane thinset layers). So when placing the flanges, do you cut that pipe to length and install flange for inspection and use a plug for rough in, or do you set it to 11/2” with built in test knock out and hope the layers fit well? Last flange - do you sit it on finished floor? That is what seems to make sense based on toilet and wax rings thickness.
last question. If the washing machine trap is above 6” and under 18” by code, the standpipe (IPC) should be 30” above that, can it be taller? I couldn’t find an answer for this
thanks all. Happy plumbing .
first question is about pipe fall. I understand what fall is required, and set up a level with a block so im not guessing. Question is this : for example on the main 3” drain, if a 3” combo is installed plumb and square to the drain line, will it have correct fall for the branch or does it need a little turn and test it with a 2’ length of pipe ? I read that the dwv fittings have the correct “Fall” built in to the fitting, but havent been able to tru verify this. We are measuring and double checking before gluing but it would be good to know.
one other fall question. On a run of 2” connecting a lavatory and bidet to main the drain, A section of 2” pipe connecting the wye from bidet to 233 combo at the main drain (about 18” long piece of 2”) the fall is slightly less than the 4’ section on the other side of the wye back to the lavatory. With hangers we got the fall looking good, without requirements. How exact does the fall need to be to work properly? are there acceptable tolerances or does it need to be dead on?
2nd. When installing toilet flanges, finished floor for both will be approximately 11/2” above subfloor (tile, durock, membrane thinset layers). So when placing the flanges, do you cut that pipe to length and install flange for inspection and use a plug for rough in, or do you set it to 11/2” with built in test knock out and hope the layers fit well? Last flange - do you sit it on finished floor? That is what seems to make sense based on toilet and wax rings thickness.
last question. If the washing machine trap is above 6” and under 18” by code, the standpipe (IPC) should be 30” above that, can it be taller? I couldn’t find an answer for this
thanks all. Happy plumbing .
