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Skylight Flashings & Manufacturers

There is nothing quite like the light you experience from a skylight or the sound of rain drops glancing across the glass surface. Skylights are truly objects which can soothe the senses. The five skylights in my home fill our kitchen and sunroom with vast amounts of positive energy.

Water Worries

Unfortunately, many homeowners experience anxiety about the installation of skylights. They find it very unsettling when a contractor proposes cutting a hole in the roof of their home. More than one of my customers grimaced at the thought.

These thoughts, historically, are well founded, as many skylight installations in the past were prone to leakage. These leaks (as well as present day leaks) were caused by a combination of inexperienced installers and poorly designed skylights.

The skylights of 20 to 25 years ago relied upon flashing systems which were constructed at the job site. This was OK, as long as a professional roofer was part of the installation team. Rarely, however, was this the case. Countless numbers of skylights were installed by carpenters who happened to carry with them the ever present caulk or 5 gallon bucket of roofing cement. Both of these compounds are not acceptable as a permanent roofing material.

Pre-engineered Skylight Flashings

Skylights made a quantum leap forward approximately 15 years ago. The smart manufacturers became acutely aware of the leak problems and the bad name their products were receiving. They, in turn, developed flashing systems specifically designed for their products.

These flashing systems, when installed according to manufacturer's recommendations, provide for leak free installations in all but the most severe weather conditions (hurricanes, violent wind driven rain, ice dams, etc.) I have installed hundreds of these systems. Not once has a customer called me with a complaint concerning a leaking skylight. There is no substitute for these pre-engineered flashing systems.

Just What are They?

Flashings are the nemesis of homeowners. Ninety percent of all roof leaks are a result of flashing problems. Many homeowners experience confusion concerning flashings. I'm convinced that this confusion is based upon the fact that very few homeowners have had the opportunity to 'walk or crawl' a roof to see just what they are. Flashings are simply transition materials. They make the transition between roofing materials and things that project or stick through roofs. This linked article speaks to this subject.

The best flashing systems are constructed of metal. When constructed at the jobsite, these metals almost always require solder to fuse together separate pieces of metal into one leak-free piece. Caulk or roofing cement simply will not do. Only experienced roofers can construct soldered flashings.

Skylight manufacturers responded to this by making the flashing system an actual component of the skylight. These flashing systems require no solder, caulk, or roofing cement. They rely on simple gravity to keep rain water from entering your house. This is the same principle which has kept water from coming into hundreds of thousands of homes which employ sound roofing techniques.

The advantage to these pre-engineered systems is both leak free and rapid installations. Site built soldered flashings can take hours alone to fabricate. Pre-engineered flashings can be installed in minutes!

The Shaft

The most dramatic skylights are those that have flared shafts or light tunnels. The sunlight which enters the skylight must be funnelled into the living space. There are any number of ways to construct skylight shafts. However, more light will enter the room or space if you widen the shaft as it runs from the skylight to the ceiling below. The effect is comparable to operating a flashlight that has a lens which can be adjusted from a narrow beam to flood light position. Flared skylight shafts act like flood lights.

Complex skylight shafts can take time to construct. Often structural work has to be performed to transfer loads from ceiling or roof framing members that are altered to create the light tunnel. This type of work is not to be attempted by 'weekend warrior' homeowners who think they are master carpenters. If your house is constructed with prefabricated roof trusses, absolutely do not cut these framing members. Truss alteration is not always possible. In the few instances where it can be done, it must be approved by a structural engineer.

If installing a skylight shaft, always make sure to insulate the tunnel prior to applying the wall finish. Vast amounts of energy can be lost through these uninsulated spaces.

Also, always paint these shafts or tunnels with flat wall paint. Semi-gloss or gloss paint will accentuate any imperfections in the walls.

Engineered Flashing Skylight Manufacturers

  • Andersen Corporation
  • Pella Corporation
  • Roto-Frank of America
  • Velux-America

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