A site-built flashing system that nestles a tube skylight into a tile roof, without shiny, exposed metal flashing
The 'correct' way to flash a tube skylight in a tile roof is to leave about six inches of metal exposed below the skylight. Sure, you can paint it to match the roof, but the skylight still sticks out like a sore thumb. Eric uses a small wood frame and peel and stick to create a draining underlayer so that roof tile can cover the flashing below the skylight. The result looks exceptional and directs water away.
Step by step directions for flashing a tube skylight:
1/ Remove all of the roofing tiles around the skylight. About two feet from each side of the skylight
2/ Apply roof cement around the edge of the skylight flange. Center flange over hole and place. Nail the perimeter.
3/ Make a frame around the skylight using 1x stock. Align the sides of the frame with tile contours so that the tile can overlap the frame. Eric spray paints the wood, flashing, and the top edge of the roof tiles with asphalt primer so that the peel and stick sticks to the parts after he peels it.
4/ Two peel and stick sheets flash around the skylight. The upper one overlaps the lower one which overlaps the roof tile below by about five inches. The wood sides of the frame keep water channeled into the peel and stick trough. Roof tiles go back on, and the row below the skylight covers the five-inches of peel and stick below. These lower few roofing tiles are attached to the roof with mastic or foam.
5/ Roof cement is applied around the tube before the remaining tiles are replaced.
Next, Eric flashes a curbed skylight but doesn't go into a lot of detail, so we are going to skip it here. A water-test on both skylights indicate that the flashing works. Eric also goes into a bit of a diatribe on inexperienced roofers thinking they know how to do everything. Like young drivers...
—Eric Garcia is a roofing contractor in the LA area who posts a lot of videos to YouTube. He is a believer in respecting experienced trade contractors.