A skylight is a common component of modern architecture and is widely used in residential, commercial and industrial structures as an efficient way of bringing in natural light. Architects and property owners alike value it for the numerous visual and functional benefits it offers. Read on to discover the skylight meaning and learn all about a skylight, its types, design considerations, benefits and limitations.
What is a Skylight?
A skylight can be defined as a window or transparent/ translucent architectural element located on the roof of a building. Such elements have been used in architecture since time immemorial, the earliest known example being in the Pantheon—where a small opening in the roof dome allows sunlight inside—built during ancient Roman times. A skylight is an effective method to allow sun light in roof slabs without having a complete glass roof and also offers several other aesthetic, functional and structural advantages in buildings.
Benefits of a Skylight
The following are some of the important benefits provided by skylights:
- Light and Ventilation: Roof windows ensure maximum natural light and facilitate air movement. They are especially beneficial for buildings on tight urban plots, where wall windows and openings are difficult to accommodate.
- Aesthetics: Sky lights flood sunlight into rooms, creating a play of light and shadows with different patterns throughout the day. The use of different materials and colours in skylights can also contribute to enhancing space aesthetics.
- Space Enlargement: Bright light facilitated by the skylight glass can make spaces feel much larger than they actually are. These elements are also typically designed in double-height or taller spaces, further making the spaces seem bigger.
- Physical and Emotional Wellbeing: Adequate natural light and ventilation, along with the enhanced connectivity to nature (the sky) provided by a ceiling window has several health benefits. These include an increase in productivity and concentration and improved moods.
- Energy Efficiency: Due to the increased natural light in spaces with a ceiling skylight, the dependency on electricity for lighting during the daytime is reduced. This lowers utility bills and promotes sustainable building practices.
Types of Skylight Roof Design
Some of the common types of skylights available are:
Sloped Skylights
The roof glass for sunlight in skylights is generally sloped and facing a particular direction. A sloped skylight typically consists of three vertical surfaces mounted on a roof slab in a triangular formation, upon which one sloped transparent/ translucent panel is fixed to allow sunlight. Orienting the sloped surface towards a favourable direction, such as the North direction in India, brings in optimal natural light.
Flat Roof Skylight
A flat skylight consists of a raised perimeter (which may be made of masonry, concrete or other materials) upon which a flat transparent/ translucent panel is mounted. Although such skylights are easier to access and clean from the rooftops, water drainage can be a difficult problem to tackle. Penetration of direct overhead sunlight into spaces can also cause overheating issues and glare. However, a frosted skylight can solve this issue.
Skylight Window
A skylight window can be defined as an openable window located on the roof of a building. Such skylights can be used to bring in fresh air, which is especially useful in areas where wall windows are difficult to accommodate or open. They create an open-to-sky in-house effect, allowing natural light and ventilation to flow smoothly. However, these are generally difficult to access and may not always be a practical option.
Light Tunnels
A light tunnel consists of a tubular or rectangular shaft with a glass panel (or other transparent material panels) fixed at the top. The shaft is lined with reflectors that help transport and distribute the light to its bottom, flooding spaces with light. Such tunnels are commonly used in basements and storage rooms with no other means of enhancing natural light, where providing regular windows is not practical.
Skylights with Custom Shapes
Skylights can be customised to create the desired shapes. Some of the unconventional skylight shapes available are domes, barrel vaults, pyramids, cylinders and arches. Although they can be made with different materials like steel, aluminium and uPVC, such shapes require extensive detailing to prevent issues like water seepage and are typically more expensive than regular shapes.
Skylight Design Considerations
- Sun Pathways: The movement of the sun across seasons and days ascertains the amount and intensity of light entering through a skylight detail. In India, the South direction generally experiences the harshest sunlight, while the North receives the most favourable light quality.
- Skylight Material: Different materials can be used for framing (masonry, concrete, steel, aluminium, uPVC, etc.) as well as for the translucent portion (glass, plastic, perforated screens, jaali blocks, etc.) of skylights. These materials influence the amount of light diffusion and thermal comfort in spaces.
- Sealing: All the joints between the roof slab/ roof structure and the skylight frame must be properly sealed and waterproofed to prevent the penetration of water, moisture, dust and air to ensure functionality.
- Slope: Adequate slopes must be provided on the skylight to ensure that water and dust do not get accumulated on its surface. The slope direction and angle also determine the light quality inside the space.
Limitations of a Skylight Roof
Despite the many advantages of skylights, one must consider the following drawbacks before installing them:
- Maintenance: Due to the increased height at which a residential skylight roof is generally located, it can be difficult to access it from the inside for maintenance and repair. The glass surfaces (exposed to external weather conditions) also require frequent cleaning to ensure that the light quality and visual appearance are not affected.
- Water Issues: Unless properly sealed and waterproofed, a skylight can cause issues like moisture build-up and water leakage or seepage. If left unchecked, these can lead to mould-growth and even structural damage to the roof, compromising building safety.
- Excess Glare and Heat: Unless frosted glass (or any other translucent material) is used in the skylight, it can cause excess heat and glare inside a house when positioned in the wrong direction. Absorption of direct and undiffused UV rays can cause thermal discomfort and health issues in occupants, apart from physical damage to belongings like furniture and sensitive paintings.
Getting the Best Skylight Design for Home
Skylight selection, along with precise design and installation to ensure its proper functioning, can be a tricky task. If not installed or designed properly, skylights can cause major damage to a building and put its structural integrity at risk. Brick & Bolt, a dominating force in the building industry, therefore provides end-to-end construction services with assured quality. 470+ quality checks are conducted for every building project and an additional 10-year structural warranty is provided to guarantee only the best quality for the construction of your home. Contact Brick & Bolt today to get experts to design and build the perfect skylight in your dream home today!
Hemali Patel 
Apoorva H P Achar