We know there's no vent for the tub/shower drain. :( It has always been a slow drain. Now, after a short shower, water will seep from under the tub and from under the toilet. When we have plunged the drain, sand comes up. How can we add a vent without having to demolish the bathroom? The toilet is next to the tub and the sinks are next to the toilet.
Thanks for your help.
Ariela

Hi Arela,

A few questions, How old is your house? Is this a "added bathroom"? Do you have a basement or are you on a slab?
First things first. You have a blocked drain line with a possible broken pipe.
If the lavatory has a vent snake the vent from the roof. Put out enough cable to reach the base and about 20 feet more. Good luck, Tom