For convenience on the main floor anywhere off the kitchen makes sense as does a mudroom or off the garage.
Floor drain in upstairs bathroom.
The drains go beneath it to the basement but notice the aav under the lavatory sink.
The center of the lav s drain is located 18 approximately above the finished floor.
After thoroughly cleaning the bathroom approach different corners and drains above the bathtub or floor and try to determine where the smell is strongest.
If you have a second story bathroom the problem could be in.
This means that it joins a drain for a first floor half bathroom under stairs.
Run cold water for ten minutes to finish rinsing the drain.
A damp spot or worse a continuous drip from the ceiling overhead signals trouble.
Another possibility is continuous dripping of water.
Do consider where you can tie in to existing plumbing.
On a second floor try to position it so it backs onto a bathroom.
Rinse away the bleach with a gallon of hot water dumped slowly down the drain.
If something is leaking in your upstairs bathroom you will probably know by the stains on the ceiling below it.
Temporarily secure the tops of the pipes against a stud in the wall by placing a pipe strap around each line and tapping the provided nails into the studs.
Also notice the drain is centered right in the middle of this 30 inch vanity.
In some circumstances the ceiling will be continuously damp and other times it may cycle between getting wet and drying.
Once you understand where the stink comes from you can get rid of it.
How to fix a leak from the upstairs bathroom.
The bathroom sink s water lines are roughed in 3 inches above the drain.
Have a helper guide the tops of the pipes into the opening in the upstairs bathroom wall.
Measure 21 inches approximately above the finished floor.
Next pour bleach down the drain close the bathroom door and allow to sit for two hours.
The noise will keep you awake.
The picture shows this bathroom.
This will hold the lines in place until you are ready to add furniture and individual fixtures.
In most cases it occurs from the sewer where accumulated organic waste hair and soap create a biofilm.
Don t put the laundry too close to sleeping areas.