The bathtub in my 50 year old home does not have a trap installed and occasionally some sewer gas smell comes through the drain. I would like to add a trap to prevent this and I have reasonably good access behind the tub, but not a lot of space between the drain tee and the pipe to the main bathroom drain to fit a P-trap the normal way facing away from the tub. (see photo - current drain on left, proposed plumbing on right)
As you can see there is currently a 90 elbow directly off the drain tee (where the trap should be) which then has a short run through a notched joist before another 90 elbow that feeds into the main drain pipe. Since there's no space between the tee and the elbow below it, I figure I'll probably have to cut out and replace the tee and then extend the cut pipes with couplers. Then, would it be acceptable to install a trap as I illustrated in order to avoid interfering with the joist? Since the existing notch in the joist is directly behind the tub drain, I'll probably have to widen it a little and maybe change the other 90 elbow to a 45 to better line up with the p-trap.
Any problems with this solution or alternate suggestions?
As you can see there is currently a 90 elbow directly off the drain tee (where the trap should be) which then has a short run through a notched joist before another 90 elbow that feeds into the main drain pipe. Since there's no space between the tee and the elbow below it, I figure I'll probably have to cut out and replace the tee and then extend the cut pipes with couplers. Then, would it be acceptable to install a trap as I illustrated in order to avoid interfering with the joist? Since the existing notch in the joist is directly behind the tub drain, I'll probably have to widen it a little and maybe change the other 90 elbow to a 45 to better line up with the p-trap.
Any problems with this solution or alternate suggestions?