One drain outlet is sufficent provided the drain outlet to the sewer line or to the gully outside has the correct gradient fall.
typically shower drains are 2"
You can use an AAV for each of these. This prevents having to cut the roof.
The drain is plugged somewhat between the upstairs and downstairs. Need to snake the drains.
The shower gurgles because the water is going down the pipes.
Use "Draino Gel" it works well.
What is the classification of household cemicals that are used to unclog drains?
we need storm drains because it helps the city not over flood
The drains for the shower, toilet and sink all connect to a common line. Assuming the toilet is not backing up, the problem indicates that there may be a partial blockage, enough so that some of the toilet flow is backing up through the shower drain line. You need plumbing repair. The shower leak you mention should only be in the shower, or else you have a broken drain line as well.
Yes. Drain line must be sized accordingly for number of showers being tied into it.
I dont know, i found one in my bathroom sink today... no idea how it got there :-/
Down the kitchen garbage disposal. It will kill bacteria and is not harmful to pipes or the environment. Any smells coming from drains will be neutralized so bathroom drains and shower drains are also a good choice to dispose of vinegar for it's mild acid content.
Water in inappropriate places, like floors and countertops, and drains and hair anywhere in the shower.