What to Do With a Skylight Shaft?

Insulation

• The skylight shaft in your house runs from the roof’s surface, through the attic space and to an opening in your living space’s ceiling. Because the shaft passes through the attic, which may not be insulated, the skylight shaft may be a source of cold air entering your house in winter and hot air in summer. A lack of insulation can cause condensation to form inside the skylight shaft as the warm air in your house contacts the cold air inside the attic. As condensation accumulates, it runs down the shaft and can look like the skylight is leaking at the roof.

Leaks

• Your skylight shaft becomes the pathway for leaks when the skylight’s seal with your house’s roofing material is not working properly. The cap that goes on top of the skylight shaft has a metal flashing piece that fits on or under the roofing material, creating a watertight seal. If the flashing is damaged or not installed correctly, water can enter the skylight shaft. If your skylight’s flashing doesn't stay attached to the roof, remove the nails holding it down and use screws instead. Failure to repair the leaks inside a skylight shaft can result in paint damage, the shaft’s drywall becoming soaked and ruined, and mold growing inside the shaft. Once you see moisture, address the problem immediately before it becomes larger.

Enlarging

• Skylights offer natural lighting in a room, but you can further increase the room’s natural lighting by enlarging the skylight and its shaft. Skylights come as squares or rectangles and in a variety of sizes. A roofing contractor can help you find a skylight that provides enough light for a room and also fits your budget. When you install a larger skylight, you'll need to demolish the old skylight shaft and install a new shaft. Depending on the placement of the new shaft, you may need to move ceiling-mounted light fixtures inside your house.

Light Filtering

• Although a skylight provides natural light in a room, the sunlight may cause some materials like cabinetry and upholstered furniture in your house to fade. You may install a sheet of ultraviolet-filtering material to place inside the skylight shaft to filter out sunlight rays that would harm anything in your house. You may find other shading solutions at your local home improvement store. Shades that fit inside the skylight shaft retract with the use of a remote control or a crank mounted on or near the shaft’s opening.