The Only Way to Trim Exterior Windows
The key to durable trim and minimal trips up the ladder is to assemble it first and install it later.
Trimming exterior windows can be an ordeal, unless you learn the lessons that Seattle builder Mike Vacirca presents in this article. Vacirca’s process for exterior windows begins by assembling the trim first, then installing it as one piece. He starts by measuring every window to be sure he has correct dimensions. Vacirca then mills the windowsills, and is sure to keep the casing square during assembly. Finally, he installs the unit, nailing in the casing but screwing in the sill.