Garage Skylight – Enhance Natural Light and Ventilation
It looked as if my “skylight ship” had sailed. Last fall I wanted to install a skylight when I remodeled my bathroom, but I had to cut costs somewhere, and the skylight got the ax. I was bummed.
However, my disposition brightened last summer when I was planning to build a new garage. I convinced myself — and my wife — that this was the time to install a skylight (after all, we’re not getting younger). The No Leak Skylight by Velux helped us see the light. With three layers of water protection and an impressive set of warranties, the skylight is aptly named. In addition, it’s easy to install and has a high-end look with a low profile and an updated curved architectural design. Best of all, this model opens and closes by remote control and boasts a moisture sensor that shuts the window automatically when the sensor gets wet.
Check out this Velux video, which covers the new no-leak features of this skylight and includes an overview of the installation. Then follow the steps below.
Step 1: Determine the skylight’s placement and install blocking.
Once you know where you want the skylight, install blocking between the roof trusses and above and below where the opening will be. I wanted the skylight directly above my workbench and on the west-facing slope of the roof so it would catch the afternoon and evening sunlight. Morning light would have been nice, but a neighbor’s maple tree to the east blocks morning sun.
Step 2: Cut the opening in the roof.
Use a reciprocating saw to cut an opening that fits the skylight. (The installation manual lists rough opening sizes for various models.) Remove the sheeting material and let in the natural light . You can see what a difference daylight brings to the garage interior.
Step 3: Remove the existing roofing underlayment.
The amount of underlayment you’ll need to remove varies depending on the skylight you select; I removed 4-1/2 in. around the bottom and sides and 7 in. around the top.
Step 4: Mark the corners.
Use a speed square to extend the lines of all sides of the opening at the corners. This creates an ‘L” at each corner, which will help in positioning the skylight.
Step 5: Position the skylight and fasten it in place.
Push the unit through the opening. This job is easier with one person working from below and another from the roof. Notches at the skylight corners must line up with the “L” lines from Step 4. Once the skylight is centered, nail it to the roof.
Step 6: Remove the cladding and add adhesive underlayment.
Remove the cladding that is on the skylight (but save it) and then wrap the skylight frame in the adhesive underlayment supplied with the skylight flashing. Apply the bottom strip first, the side strips second and the top strip last. Follow the manufacturer’s instructions for cutting the corners of the adhesive underlayment so that you create a waterproof membrane beneath the flashing and roofing material.
Step 7: Install flashing.
Flashing comes with this Velux unit. Position the sill flashing tight against the skylight bottom and attach it with roofing nails. Then install the step-flashing pieces up the sides. Follow the manufacturer’s instructions to make sure you overlap the step flashing properly as you work up the sides, and avoid driving nails that would be exposed in gaps between shingles. Interweave step-flashing pieces with roofing materials, and fasten the pieces to the roofing with nails.
Step 8: Replace the cladding.
You did save the cladding removed in Step 6, right? Now, re-apply the cladding.
Step 9: Install saddle flashing.
This is the flashing that runs across the top of the skylight and partly down the sides (photo 9). Attach the saddle flashing at the sides by turning down the skylight tab that fits through a saddle-flashing slot. Fasten the saddle flashing to the roof with roofing nails.
Step 10: Power up the skylight.
A 20-ft. cable (supplied with the skylight) that connects to a junction or outlet box supplies the power to open and close the skylight by remote control. Before you plug in the cable, peel off the backing on the rain sensor and stick the sensor to the sill flashing; then attach the wiring from the sensor to the wiring from the skylight opener.
Considering the hours we’ll spend in the new garage workshop, installing the skylight was a brilliant decision. The natural light dramatically enhances the atmosphere of the shop, and the additional ventilation helps keep the entire garage cooler, an especially nice bonus when we’re storing or retrieving items in the attic. And thanks to the moisture sensor, we’ll never have to worry about unexpected showers raining on our projects.