How to Check Window Flashing Before Siding Covers the Mistake

On a residential build, a window passed the quick visual check but leaked during the first hard rain. The siding was already up, so the repair cost more than the original install. The problem was not the window itself. The sill pan had a reverse slope and the side flashing was lapped in the wrong order, sending water behind the housewrap. Now I check windows before siding with a simple sequence…