Skylights, situated on the roof, can contribute to the house’s thermal dynamics, leading to an inadvertent increase in heat during the summer months and an unwelcome dissipation of warmth in the winter. However, advancements in skylight technology help to offset these potential challenges. Companies incorporate a variety of glazing methodologies such as heat-absorbing pigments, insulated glazing, low-emissivity (Low-E) coatings, or translucent insulation sandwiched between multiple glazing layers to enhance their energy efficiency. These innovations can result in considerable energy savings by reducing reliance on artificial light and heating systems.
Tubular Skylights
An interesting evolution in skylight designs involves the use of sun-tracking, open-sided cylinders, large lens-like elements, or mirrored reflectors installed adjacent to a traditional skylight. These designs direct daylight into the space below without the accompanying daytime heat or nighttime heat loss. The unique configuration includes a mirrored tube or “light pipe” attached to a diffusing lens, which is either mounted on or recessed into the room’s ceiling. This feature is a standard element of most tubular skylights. However, it’s important to note that while they offer excellent light dispersion, tubular skylights do not provide an outside view or ventilation.
Ventilation
In addition to their daylighting function, skylights also facilitate ventilation. An operable skylight allows the escape of hot air that tends to accumulate near the ceiling, thereby promoting airflow. These skylights typically open outward from the bottom, with some models featuring a small, hinged panel for venting. To open these skylights, one can manually use a rod, chain, or crank, thereby providing a natural and energy-efficient cooling system.
Roof Windows Skylights of a larger scale, which can also serve as emergency exits, are often referred to as “roof windows”. Typically, you would position them within comfortable reach from the floor, enhancing safety and practicality. This can be an essential feature for building regulations and adds a unique architectural element to your home, while also providing the same benefits of light and ventilation.
Automated Skylights
Advancements in technology have given rise to automated skylights that incorporate electric motors or pneumatic devices for smooth operation. Certain models are designed with moisture sensors, ensuring the skylight automatically closes at the onset of rain, thus offering added convenience and protection against unexpected weather changes.
Skylight Design Considerations
When contemplating the installation of a skylight in your home, it’s vital to consider the best type and location for maximum benefit to your home’s natural lighting and air circulation.
Energy Efficiency
Understanding the energy performance ratings of skylights is crucial in making an informed choice that suits your local climate and your home’s architectural design. The ENERGY STAR® program has established minimum energy performance rating standards for skylights based on the climate. These standards are predicated on detailed ratings from the National Fenestration Rating Council (NFRC). It’s advisable to look for skylights that bear the NFRC and ENERGY STAR labels, signifying their energy efficiency.
However, these standards do not consider a home’s specific design. Therefore, if you’re building a new home or considering a significant renovation, it’s an excellent opportunity to integrate the skylight design and selection into the overall design of your house.
The size of the skylight significantly influences the level of light and the temperature in the room below. Typically, the skylight should constitute no more than 5% of the floor area in rooms with numerous windows and up to 15% of the floor area in rooms with fewer windows.
To leverage daylighting and/or passive solar heating, the skylight’s orientation matters. North-facing skylights provide consistent but cooler illumination. East-facing skylights yield maximum light and solar heat in the morning, whereas those facing west provide afternoon sunlight and heat gain. South-facing skylights offer the highest potential for beneficial winter passive solar heat gain, but they can also lead to unwanted heat gain in summer.
To mitigate unwelcome solar heat gain, consider placing the skylight in the shade of deciduous trees or installing adjustable window coverings on the interior or exterior of the skylight. Exterior shades tend to be more effective at reducing summer heat gain. Moreover, some skylight units feature special glazing that assists in controlling solar heat gain, further enhancing energy efficiency.
Glazing
Glazing, a critical part of skylights, typically uses materials like plastic or glass. However, you can also use other advanced technologies for enhanced solar heat control. The glazing you opt for may vary depending on the performance you expect from your skylight and its placement in your home.
Plastic glazing, being relatively inexpensive and less prone to breakage than other materials, is a popular choice. However, its downsides include a tendency to scratch easily, and over time, it may become brittle and lose its original colour. Unless coated with a specific film, many plastics allow a significant amount of ultraviolet (UV) rays to pass through, leading to increased fading damage to interior furnishings.
Among plastic glazing materials, acrylics and polycarbonates are most frequently used. Acrylics are less expensive but weaker than polycarbonate. While polycarbonates boast high impact resistance, they can yellow over time due to prolonged exposure to sunlight.
On the higher end of the price spectrum, you’ll find skylights glazed with glass. Glass holds up better over time compared to plastics, maintaining its clarity without discolouration. It’s essential that glass used for skylights undergoes a “safety glazing” process, encompassing both tempered and laminated glass methods. These processes ensure that if the glass breaks, it shatters into small, less dangerous pieces, enhancing the safety profile of your skylight.
Shapes
Manufacturers produce skylights in a variety of shapes and sizes to meet diverse architectural requirements and aesthetic tastes. Commonly seen shapes include rectangles, circles, ovals, diamonds, triangles, multi-sided designs, and tubular forms.
Typically, non-rectangular units utilize plastic glazing, but the more superior models incorporate glass. You can find glazing in diverse shapes, such as flat, arched, domed, pyramidal, or ‘warped plane’—a design that’s flat on the lower side and concave on the higher side. Among these, the pyramidal, arched, and domed shapes offer an advantage with regard to positioning due to their raised design, which permits light ingress from more acute angles compared to flat or warped plane units.
The slant or curve in the glazing assists in shedding moisture and leaves, reducing maintenance needs. Moreover, these skylight designs eliminate the requirement for extra framing that would otherwise be necessary to angle a flat skylight for optimal drainage on flat or low-slope roofs.
Tubular skylights distinguish themselves by their smaller size compared to other skylights. They are designed with roof-mounted lights or solar collectors, enhancing their daylighting capacity without needing to increase their size. As the rooftop solar collector occupies a small surface area, tubular skylights effectively minimize heat loss during winter and heat gain in summer, contributing to energy efficiency. Additionally, their compact size allows for subtler integration into a home’s architectural design, ensuring they complement rather than dominate the aesthetic.
Installation
For maximizing energy efficiency, you must install even the best skylights correctly. You should strongly consider hiring a professional to install your skylight. In addition to adhering to the manufacturer’s guidelines, the installer should consider factors such as slope and moisture control. You must properly insulate and seal the skylight shaft in the attic, the part that connects the skylight to the home’s interior, to prevent energy loss and shield against weather elements.”
Slope
The slope or tilt of a skylight significantly influences the amount of solar heat gain. A skylight with a low slope tends to let in more solar heat during the summer and less in the winter, which is counterproductive to maintaining a comfortable indoor temperature.
A useful rule of thumb to optimize the energy efficiency of a skylight is to set the slope equal to the geographical latitude of your location plus an additional 5 to 15 degrees. This will help to maximize solar heat gain in the winter (when you need it) and minimize it in the summer (when you don’t). For instance, if you’re installing a south-facing skylight in Columbus, Ohio, which is located at 40° north latitude, an optimal slope would range between 45° to 55°. This setup would harness solar energy effectively according to the seasonal requirements.
Moisture Control
Water leakage is a prevalent issue with skylights if they’re not installed properly. To circumvent such problems, consider the following measures:
- Elevate the skylight: Position the skylight above the roof surface to aid in the run-off of water and reduce the likelihood of water pooling.
- Install a curb and flashing: A curb refers to a raised, watertight edge designed to guide water away from the skylight. Together with flashing, which helps direct water towards the roof’s drainage system, these installations can greatly reduce the risk of leakage.
- Ensure thorough sealing: Properly seal all joints to prevent water from seeping in.
- Adhere to manufacturer’s guidelines: Follow the manufacturer’s instructions for installation to ensure that the product performs as intended.
In addition, it is wise to apply a layer of sheet waterproofing over the flanges or flashing of the skylight. This layer, typically positioned beneath the finishing roofing material, serves as an additional barrier against ice dams, which can cause water to back up and leak into the house.
Avoid using water diversion devices such as roof crickets or diverter strips. Despite their purpose to redirect water, they can frequently cause additional issues.
Choosing the Right Contractor
Selecting a knowledgeable and experienced contractor is crucial for the correct installation of your skylight. Ensure that your chosen contractor is licensed and insured, and has a track record of successful skylight installation. Ask for references and read reviews to understand the experiences of previous clients.
Site Assessment
Before the installation, a thorough site assessment should be carried out. This involves evaluating the roof’s structure, the location of plumbing and electrical systems, and the interior aesthetics of your home. The assessment will help in identifying the best placement and size for the skylight.
Skylight Type and Placement
Deciding on the type of skylight is another important factor to consider. You can choose from several options: fixed skylights that don’t open and are designed purely for added light; ventilating skylights that open to enable air circulation; or compact tubular skylights for smaller spaces. The placement of the skylight should be done keeping in mind the path of the sun and the room’s lighting needs.
Interior Work
Once the skylight is installed, the interior portion of the skylight shaft needs to be finished. This might involve framing out the tunnel and then drywalling and painting it. The style and colour should blend with the existing decor of the room.
Post-Installation Inspection and Maintenance
After installation, ensure to thoroughly inspect the skylight for proper sealing and functionality. Also, plan for regular maintenance. This could involve cleaning the glass, inspecting the seals and flashing, and ensuring the skylight opens and closes smoothly (for ventilating skylights).
Remember, a well-planned and executed installation process can greatly enhance the performance and lifespan of your skylight, providing you with many years of natural light and possibly even reduced energy costs.
In conclusion
Skylights can undoubtedly transform your home, enhancing its aesthetic appeal and energy efficiency. The selection, design, and installation of a skylight require careful consideration and planning, but the rewards in terms of improved natural lighting, potential energy savings, and increased property value make it well worth the effort.
Remember that the key to successful skylight installation lies in understanding your specific needs, the architectural nuances of your home, and the local climate. Partnering with an experienced professional can ensure a seamless installation process and long-term functionality.
In this guide, we’ve walked you through the journey of choosing and installing skylights, shedding light on essential factors such as energy efficiency, shapes, glazing types, moisture control, and installation aspects. We hope this guide serves as a valuable resource, aiding you in making an informed decision about enhancing your living space with skylights.
So, are you ready to invite more sunlight into your home and transform your living space into an oasis of natural light? With the right skylight in place, your home can indeed shine brighter.
