Skylights are an excellent way to enhance a home and bring in more light that is natural. The skylight has been popular since the 1970s but in recent years, more and more homebuilders and homeowners are finding enjoying them more, as technology and materials have improved. If you are thinking about adding a skylight to your home, using penetrating roof materials and framing the opening properly are critical to success.
To install a skylight, you do not have to be a professional. However, do keep in mind that there are occasions when a professional should handle the job. Sometimes, even a top professional will need assistance, in certain situations. Therefore, use common sense and call in the Calvary, when and if needed. This would especially be the case if the skylight will be larger than 48 inches, if your roof has a slope of more than 6 to 12, or is made from material that can be slippery. If your particular roof is made from roofing felt with hot-mopped asphalt or polyurethane foam, chances are you can accomplish the task on your own. Before you get started, be sure to check with your local building code to make sure you do not need a permit, your homeowner�s association to ensure you can install a skylight, and your insurance company to check on changing premiums.
First, you will need to determine where the skylight will be installed. Once you have the room/spot located, go up inside the attic to make sure there are no obstructions that would halt the project. For example, there might be special support beams or an attic fan system. Next, you want to measure to the center, going between the joists, and then tap a small nail up through the ceiling (about 4 to 5 inches long). This helps you find the exact center from the roof, simply by locating the protruding nail.
Now, you want to use the stand of the ceiling frame as your template, marking the ceiling with a white pencil or piece of chalk to ensure the nail hole you made is indeed the exact center. On the ceiling side, use a key hole saw to cut along your pencil/chalk line, remove, and save the piece.
The next step involves inserting the ceiling frame, attaching it with a one and one-half-inch screw and plastic lug. The lugs are placed on the top side of the ceiling, the screws fastened through the holes of the ceiling frame, up through the ceiling, and into the plastic lugs. Be sure you tighten them down well. Now, finish off with the plastic caps that go into the screw heads.
From inside your attic, you want to use the most direct route possible for tubing to reach the roof. Just remember that the tube has to fit between the rafters. Position the skylight if possible so it has a southern exposure, with the shorter, straighter, and tighter tube for the highest level of performance. Next, measure the center between the rafters and tap a nail through the roof, again from the ceiling side.
Using your ceiling cutout (template), mark a circle on the surface of the roof, going around the base of the template. Just be sure that nail hole is in the center position where the skylight will be installed. With a jigsaw, cut around the circle, removing the section of unwanted roof material and sheathing.
Next, you will attach the tubing to the top frame, pulling over the stainless steel ring on the underneath section of the skylight frame. The four tabs should be bent outwards through the tubing, and then bent into a hook shape as a means of holding the wire. Wrap these around the junction of the skylight and then flexi-tube about three times using PVC tape, covering the tabs.
The next step is to measure the length from the top of the roof�s surface to the top of the ceiling as a way of determining how much flexi-tube you will need, allowing extra for any angles and bends in the tube. Stretch the flexi-tube and then cut it to the length you need. Pull the loose end over the stainless steel lower ring, attaching it with PVC tape wrapped three times around the exterior.
Having the tubing and lower ring attached to the underneath portion of the skylight, you will slide the base into position. Make sure the upper portion of sheet metal flashing is underneath the existing roof material and the roof felt. The lower piece of sheet metal flashing will need to be on top of the roof�s surface. Fasten this into place in the same way you would standard flashing. Now, install the vent and/or blank tabs into the top frame, securing the dome with four brass screws.
Going back inside to the room, you will need to reach through the hole in the ceiling to pull the stainless steel lower ring down into the frame, attaching the frame with four sheet metal screws. Finally, you will need to install the prismatic diffuser, which can be flexed a little bit to pass through the ceiling hole easily. This will then come to rest on the top side of the ceiling frame.