Adding a drain to your mudroom floor is much like installing a shower pan. You can use the drain as the center point of a completely tiled, rinsable floor, or build it into a low tile box for washing off muddy pets and boots. Be sure to follow all plumbing and building codes and have a qualified plumbing inspector check your work before you seal up the floor. Follow these directions to install a floor drain in your mudroom.
Step 1: Decide Where to Install the Drain
Put the drain in a central spot close to the main entry to the mudroom from outside. This will confine muddy footprints to the area nearest the doorway. If your mudroom is in the garage, you will need to drill through the garage floor to reach the house plumbing pipes.
Step 2: Find the Connections to the House Plumbing
Check in the basement to find the closest pipe branch to the mudroom and mark the spot. Remove the existing flooring in an area at least 24 inches square around the proposed drain location right to the subfloor and basement ceiling. Cut up through the basement to the mudroom to ensure the most accurate drain location.
Step 3: Install the Piping and Connect to the House Plumbing
Shut off the water supply for the whole house. Use the circular saw to carefully cut a hole in the basement plumbing pipe. Cut a vertical length of 1-1/2 inch pipe measured from the basement to the subfloor level, and attach it to the basement pipe along with the pipe diameter converter. Fit the converter and drain pipe in snugly with a pipe fitting and plumber's adhesive. Attach an elbow and P-trap to the top end of the vertical pipe at the point where you want the drain cover to be.
Step 4: Install the Floor Covering
Measure and lay the waterproof base around the pipe and the drain base. Lay the floor covering, ensuring that it slopes 1/4 inch for every 12 horizontal inches, all the way around the drain, to allow water to flow down the drain directly.
Step 5: Insert the Drain Cover
Place the slotted drain cover in the top of the drain pipe. Tap it into place with a rubber mallet. Seal around the whole circumference of the drain cover with plumbing adhesive. Allow the adhesive to dry overnight before testing the drain. Once the drain cover is in place, turn the water supply back on.
Step 6: Other Options
While installing the floor drain, consider piping in a sink as well, if your mudroom is adjacent to the garden and you need to wash up after weeding and planting. You will find that a sink in the mudroom is great for cleaning off grass-stained hands, tools and garden shoes.