Step 1 · Planning, Layout, and Permitting

This is the step most people slow down on. Take it one move at a time — there’s no rush, and you can rewind the clip as many times as you need.

The first and most critical step is to create a detailed plan. Begin by measuring the space and deciding on the exact layout of the toilet, sink, and shower. Use a tape measure and marker to draw the outlines of the fixtures and the walls directly onto the concrete floor. Consult your local plumbing code to understand requirements for pipe sizes, distances from fixtures to vents, and clearances around each fixture. For example, a toilet typically requires at least 15 inches of clearance from its centerline to any side wall or fixture. Create a clear plumbing diagram showing the drain, waste, and vent (DWV) layout, as well as the hot and cold supply lines. This plan will be submitted to your local building department to obtain a plumbing permit. Do not begin any physical work until you have the approved permit in hand.