Skylights are structures that transmit light forming all or part of the roof space of a building for the purpose of daylighting. They can be traced back to the ancient roman architectures such as Pantheon and Oculus. Since the industrial revolution made advances in the production of glass, glazed closed skylights have been in use ever since. Skylights have been brought to many uses and contexts by their mass production units since the middle of the 20th century. Energy conservation has brought new design innovation, motivation, efficiency rating systems and transmission options for skylights. According to architectural glass, the earliest functional skylights would have been formed either by glass casting, Fourcault process, window glass, machine drawn cylinder sheet or cylinder blown sheet.
Among the different types of skylighting include roof windows, tubular daylighting devices, custom skylights, unit skylights and sloped glazing. Skylights have daylighting elements used to let in direct and sometimes indirect sunlight through toplighting. They also provide a visual connection of the outdoor environment to the indoor occupants and promotes sustainable building. They allow for passive solar heating and with operable units, ventilation for passive cooling and exchange of fresh air.
Types of Skylights
- An open skylight is a type of unglazed hole on the roof.
- A fixed skylight has a structural perimeter frame that supports the light transmitting portion made primarily of plastic and glass called the glazing infill. It is a non-operable type of skylight which means it does not allow for any ventilation.
- The operable skylight has an operable venting unit that used hinged sash which is attached to and supported by the frame. When this type of skylight is installed in a way that it is within reach of the building occupants, it can also be called a roof window.
- A retractable skylight is another type which rolls off the frame on a set of tracks to enable the interior of a building to entirely open to the outside. It is therefore not impended by a hinged skylight.
- The tubular daylighting device as mentioned earlier is used in active daylighting. It is a fixed unit skylight element mounted on the roof used to condense the sunlight which is distributed by a light conveying optic conduit to alight diffusing element. TDDs have small diameters which makes them ale to be used for providing daylight in smaller spaces such as hallways and bounce light in the dark corners of a room. They harvest sunlight through a roof mounted dome which are made from acrylic or polycarbonate formulated to block UV rays and capture and redirect light rays into an aluminum tubing system resembling ductwork.
- Another type of skylight is the Pavement lights which are a walk on skylights. These ones are set into sidewalks, well lit interior floors and open areas.
- Sloped glazing skylights are not the same as other ordinary skylights in that a framing system has one assembly has multiple infill panels. This type is normally designed for specific projects and installed in on-site sections. Lastly are prism lights. Even though they are only at times used as skylights, they are used to redirect the light passing through them.
Most homeowners install skylights specifically for daylighting and ventilation. Because skylights are located on the roof of your home, they are equipped with various glazing technologies to reduce gain of unwanted summer solar heat gain and the winter heat loss. Heat absorbing tints, low-emissivity coatings and insulated glazing helps reduce this impact. Some skylights even contain translucent insulation materials such as aerogel in between several glazing layers to increase their thermal efficiency. There have been recent developments in the designing of skylights in that they can now use sun-tracking, open-sided cylinders, large lens-like elements and mirrored reflectors that are mounted adjacent to a conventional skylight to let in daylight without any daytime heat gain or nighttime heat loss.
When it comes to the ventilation function of skylights, hot air which naturally accumulates near the ceiling during the hot seasons like summer is released. Ventilating skylights normally open outwards to the bottom with some units venting through a small hinged panel. Skylights can be manually opened using either a chain, a pole or a crank or they can have automated units with electric motors, blinds or pneumatic devices to operate them. Some skylights models incorporate moisture sensors that automatically closes the skylights whenever it starts raining. Instead of limiting the amount of solar heat coming through the skylights, you can also opt to install shades o blinds that can be used to cover the windows during the heat of the day and prevent sunlight from creating too much heat in the room. One thing to make sure you get when you choose your skylights is the proper window treatments. You can find skylight blinds online as most need to be custom made based on the size and style of your skylights.
Skylight Design and Price Considerations
Before deciding which skylight to buy, you must establish the type that will work best in your home and decide where to place it so that you can optimize its contribution to your home’s ventilation and daylighting. First, understand the energy performance ratings of the skylights to select one basing on the local climate and the design of your home. When buying skylights loo for NFRC and ENERGY STAR labels to ensure energy efficiency. The skylight glazing is also important to consider, choose from the plastic or glass glazing depending on the performance expected from a skylight. Although when compared to plastic, glass is more durable and do not discolor. Also determine which shape from the rectangular, triangular, oval, round, diamond-shaped, tubular or multi-sides skylights are best for you.
Installing a skylight costs between $450 to $1500 depending on the style selected. For tubular skylights, the buying price ranges $150 to $ 600 with the installation costs ranging from $300 to $600. Fixed skylights can be bought at an average price of $200 or more than that in a home depot. Deposing on the size of the window and complexity of the roofing. For vented skylights, you can buy them at a cost ranging from $300 to $ 1200 per model. The cost for installing are averaged between $1000 and $4000