How to install a new bathroom on a concrete slab or in a basement | Siouxland Homes

By James Dulley Creators Syndicate Inc.

Dear James, we are planning to add half a bathroom, but our house is built on a slab. Is it possible to add another bathroom there as there is no drain to the sewer at this point? – Charlotte G.

Dear Charlotte, adding a bathroom in a room over a basement or crawl space is definitely an easier project, but it can be done over a slab. Laying the flexible water supply lines isn’t difficult, but adding the drain to the sewer is more laborious. This is the same problem adding one to a basement.

First of all, creating detailed plumbing plans is the key to a successful project. Buy the vanity, sink and toilet and place them where you want them in the room. Precisely mark the location of all the drain lines on the floor and remove them so you have room to work. This project can get very dusty when cutting concrete. So insulate the area with plastic wrap.

There are two ways to route the installation cables. For the most beautiful appearance, the concrete slab can be dug out and the drain and supply lines routed through the trenches. Concrete is poured back into the trench to level the slab and the new floor is covered with ceramic tiles.

Another option is to install a Saniflo plumbing system over the existing concrete slab. Most of the plumbing can be hidden in the new toilet walls, but the drain lines will be exposed. An electric pump unit for the drains, which is visible, is usually located on the floor behind the toilet. A Saniflo toilet and pump unit can cost around $ 800 or more.