I am planning to remove a wall in my house. In the wall I found a drain from a former bar sink. The plumbing for the bar sink is now gone and the drain pipe heads down into the floor and the vent pipe heads up into the ceiling. I have a concrete slab on grade with no basement and I believe that this drain pipe is the end of the run under my floor slab as it is at the back of the house.

In order to remove the wall I would like to cut and cap the drain pipe at the floor slab (slab on grade – no basement) and I would also like to cut and cap the vent pipe up in my first floor ceiling. My concern is that by cutting and capping at these two locations I will create some dead air space and I am not sure if this is a hazard for gas accumulation.

Any help would be greatly appreciated.

As long as you cut and cap the drain underground with an approved cap then no issue with capping the drain line.

The vent also really isn't an issue as long as you also use an approved cap and you cap it as close to the kitchen sink vent as possible. Here, if you leave the long horizontal vent pipe in the ceiling it will eventually fill with condensation and rain water and could get heavy and break off. You either cap it off near the kitchen sink vent or add a hanger or two for support, OK?

Finally, when I say an approved cap I just mean that you can't just go capping these off with rubber jim caps... caps must be of similar materials the pipes are made of... ;)

Questions? Let me know...

Mark

Mark

Thanks for the input. Actually I was hoping to cap the drain pipe above the floor. The drain pipe has a cleanout in it which may be useful in the future. I plan to have ak need wall at this location and was going to cap in the wall. Is this an issue?

I don't think accumulation of rain water in the vent pipe will be an issue as I will be able to support the end at the location where I am capping it and can ensuree there is a slope towards the kitchen sink drain.

Let me know your thoughts... much apppreciated!

Just make sure the cleanout is accessible through an access panel or some other way that makes that cleanout obvious and your plan is perfectly reasonable... :)

Glad to help!

Mark