Step 5 · Seal and Test the New Installation

This is the step people usually slow down on. Go finger-tight first, then a quarter turn. No rush — replay the clip whenever it helps.

To prevent water from splashing behind the spout and into the wall, apply a thin, neat bead of silicone caulk around the top and sides of the spout base where it meets the wall. Leave a small gap at the bottom of the spout to allow any water that does get behind it to drain out. Now, test your work. Turn on the water to the tub and check for any leaks around the base of the new spout. Then, pull up the diverter knob. The water flow should redirect completely to the shower head. A few initial drips from the spout as pressure builds are normal, but it should not be a steady stream. Clean up your tools and remove the rag from the tub.