As far as the plumbing is concerned, adding a bathroom in a basement can be anywhere from a simple project, to a VERY extensive project. The major factor in determining the degree of difficulty, and the cost, has two very important components. These are whether or not the drains were placed in the floor for a future bathroom at the time the house was built, and, whether or not your sewer goes UNDER the foundation or THROUGH the foundation. If you have drains roughed in under the cement for a future bathroom, you are in good shape. If you do NOT have drains roughed in under the cement for a future bathroom, but you do have pipes under the floor, it will be a little more extensive. You will know this if you have any drains going from the main floor down into the cement. If this is the case, concrete will need to be broken up to find a drain under the floor, tied into, and new drains placed in the proper location. Now, the worst case scenario would be if you have NO drains under the cement AND your sewer exits the house THROUGH the foundation. There are a few reasons why this is a much more extensive process. First, since we all know that (pardon my language) sh!% rolls downhill, the system is not going to work very well if your toilet, sink and shower are LOWER than the drain going out of your house. To remedy this, a big pit with a powerful pump must be installed and your bathroom must drain into the pit. Once the water level gets high enough, the pump kicks on and discharges it UP to your sewer going through your foundation. The second problem with this installation is that a vent must be ran up into your attic, and either tied into another vent going through the roof, or it must go through the roof separately. This can be VERY tricky, especially in a two story house. On most newer homes, even if the sewer goes through the wall, there may already be a pit and drain lines roughed in.
While it is true that a bathroom in the basement will increase a homes value, it is the convenience that will be most appreciated! If you would like a quote or even some advice, we would be happy to answer any questions you may have. Between the two of us throughout our careers, we have installed hundreds of basement bathrooms with many satisfied customers!
Below are pictures from our duplex project that did not have any drain lines roughed in for a bathroom, but it did have a main drain under the cement that we were able to tie into.
