Flashing Guidelines for Skylights

Even though a skylight is used primarily for decoration and aesthetic appeal, it still qualifies as a hole in your roof. And just like any other roofing hole, including a chimney or vent, a skylight must be sealed impeccably to prevent the possibility of leaking and water damage.

THE BEST WAY TO SEAL A SKYLIGHT IS BY INSTALLING FLASHING AROUND ITS PERIMETER.

 

Here are the basic guidelines to consider for installing flashing around a skylight:

  • Take the measurements of each side of the skylight1.
  • Cut flashing materials 2 inches longer than each measurement taken.
  • Measure 1 inch longer than the end of each flashing piece and mark accordingly.
  • Measure skylight height and mark each end of the flashing strips; cut a 1 inch slot at each end mark with wire snips.
  • Place a flashing piece between two roof boards and line snipped slots with board edges.
  • Bend flashing at an 85° angle by pressing on the third board overhang.
  • Repeat this bending process with each flashing piece.
  • Fit a flashing piece around one side of the skylight; nail it securely to the roof.
  • Fold flashing tabs around the sides of the skylight and secure by screwing through flashing directly into the skylight frame.
  • Continue to install each flashing section in the same process.
  • Caulk flashing seams and clean off excess to seal completely.