Posted by roofcoadmin March 6, 2019
Skylights are not only a beautiful roofing alternative to traditional roofs but also a functional choice in terms of saving energy (they let light in during the day). However, some homeowners report that their skylights are letting in a little more than just sunlight, especially during winter — we are talking about leaks! Although skylight leaks are repairable, it’s always better to prevent them from occurring in the first place. To take preventative measures, you first need to understand how skylights are installed and potential causes for leaks.
How are skylights installed?
A skylight is a special hardened glass that is installed in a cut-out on your roof. Personnel from Winnipeg roofing company cuts a measured opening on the roof around the region you want the skylight installed. This sometimes includes cutting out both the roof and a section of the attic, should you have one. The skylight is then installed in place of the cut-out and screwed in using nails.
Special roofing paper is then installed around the skylight framework. The roofing paper is meant to prevent any moisture, rain or melted snow from leaking through the cut-out of the skylight. Insulation is then installed around the roofing paper to further prevent leaks. Finally, special insulating material known as flashing is installed around the roofing paper. The flashing is installed in two layers; step flashing and solid flashing.
What causes leaks in the skylight and how to prevent them?
- Improper installation
The most common cause is improper installation. This may arise from the use of inadequate roofing paper around the frame of the skylight. As a result, the snow that melts around the framework of the skylight seeps in and leaks through the gaps. Also, inadequate step flashing may lead to melted snow finding its way into the skylight from underneath the roofing shingles.
The remedy is to add a watertight and airtight seal around the skylight framework. Alternatively, a complete re-installation of the skylight by a professional should prevent future leakage during winter.
- Extreme condensation
The flashing around the skylight framework, as well as that underneath the shingles is designed to accommodate normal expansion and contraction of solids under different temperatures. To put it into perspective, the temperature on the outside of the skylight is much cooler than that on the inside of the house. Therefore, extreme condensation may occur during winter, weakening the flashing. As a result, melted snow sips in between the flashing, resulting in a persistent leak.
Adding insulation as well as the step and solid flashing should prevent the leak from escalating too much.
- Melting snow
The end of the winter season is characterized by a gradual rise in temperature. By this time, areas with heavy snowfall have accumulated a couple inches of snow on the roof. The rise in temperature melts the snow at a fast rate. As a result, the roof is subjected to a lot of water that could find its way around the flashing and sip through the skylight. To prevent this, you can reduce the snow cover on your roof by sweeping it off with a roof rake, or better still inviting snow removal professionals.
By now, you should have noticed that the main culprit of skylight leaks is the flashing. Schedule regular roof maintenance services to ensure your flashing and insulation is intact enough to withstand the harsh conditions in the winter.