A typical detail in wood-framed houses is a recess for a standard medicine cabinet. You make it by blocking out a rough opening 14-1/2 in. wide (usually starting 3 in. from the end of the end wall adjacent to the bath sink) and 24 in. tall. I hook my tape on the bottom plate and make marks for the blocks at 4 ft. and 6 ft. above the plate. At this point, I like to add a third block at 2 ft. off the floor. Once the walls are raised, this gives me a built-in ladder so that I can climb up onto the top plates to top off, plumb and line, or spread joists or trusses.
Jud Peake, Oakland, CA
From Fine Homebuilding 229, pp. 26-28
July 12, 2012