Cutting into Plaster

This is trickier than drywall. Remove enough plaster to expose the lath underneath. Position the template over three pieces of lath so it equally overlaps them at the top and bottom of the opening.

Trim the plaster away from the lath. Saw away the full strip in the center of the opening. Don't cut all the way through one side, because the saw will vibrate the lath when you attempt to make the second cut. Instead, make several small cuts. Saw notches in the strips above and below to finish the cutout.

Also see:
Safety in Walls, Ceilings and Attics

Glossary of Terms