When I began my roofing career in 1957 Calgary, most roofs were of a simple design, and skylights were a new and novel idea for opening up dark rooms. At that time there were many design and installation problems which often resulted in leaking and ceiling stains. The design problems have been solved for over thirty years, but installation still remains a problem because skylight installation is a very specialized field, and most companies do not have competently trained installers.
There are a few procedural basics to properly ensure ‘No Leak’ installation is executed:
1. Have a Water/Ice underlayment installed prior to the new roof;
2. Seal the skylight box, and/ or roof flashing, with the same membrane;
3. Seal all roof openings with a Styrofoam spray or proper vapor barrier tape;
4. Upon completion of the work, properly caulk all shingle/ flashing/roof joints;
5. Test the skylight with directed heavy spray, simulating rainstorm conditions; …..Lastly, and most importantly, ensure that you have a contractor offering a minimum ‘ten-year’ warranty on the installation workmanship (written and transferable).
These steps are extremely important when having standard roof window skylight (s) installed. Tubular skylights are much more resistant to leakage problems because the roof flashings are rounded, and water/ice does not collect behind them to cause damning issues—AND the inside of the attic does not have to be framed nor finished upon installation; but all you see is natural light coming into the room, you can’t see the sky, clouds, birds, etc.