Glass Roof & Skylight Singapore: Safety, Materials and Leak Prevention
Glass Roofs and Skylights in Singapore: A Safety and Performance Guide
A glass roof or skylight can transform a dark interior into a bright, airy space. It is one of the most impactful architectural additions possible. It is also one of the most unforgiving — because when overhead glass goes wrong, it goes wrong dangerously.
This guide covers the safety requirements, material choices, drainage design and leak prevention measures that make the difference between a beautiful, durable skylight and a recurring nightmare.
Why Overhead Glass Is Different
Vertical glass only needs to resist wind pressure. Overhead glass must resist:
- Its own weight — a 10.38 mm laminated panel weighs around 25 kg per sqm.
- Wind uplift — suction forces can exceed downward pressure on low-slope roofs.
- Thermal cycling — Singapore roofs swing between intense sun and heavy rain.
- Impact — falling branches, debris and, in some cases, foot traffic during maintenance.
- Water ponding — even a slight back-fall traps water and stresses seals.
Critically, if overhead glass fails, the consequences fall directly on people below.
The Golden Rule: Laminated Tempered Glass Only
For any overhead application, the glass must be laminated tempered. Here is why each part matters:
- Tempered — provides the strength to resist wind, thermal and impact loads.
- Laminated — the PVB interlayer holds fragments in place if the glass breaks, so nothing falls.
A tempered-only panel that shatters will release hundreds of small granules. A laminated panel that shatters stays largely intact and in position. For overhead glazing, laminated is not optional.
If a contractor proposes single-pane tempered glass for a skylight or roof, stop the conversation. It does not meet the safety expectations for overhead glazing.
Recommended Glass Build-Ups
| Application | Recommended Build-Up | Notes |
|---|---|---|
| Small fixed skylight | 6.38 mm laminated | Minimum for sheltered locations |
| Entrance canopy | 8.38 mm laminated tempered | Cantilever possible |
| Standard glass roof | 10.38 mm laminated tempered | Most common specification |
| Large span roof | 13.52 mm laminated tempered | Requires engineered support |
| Thermal control roof | Laminated tempered + Low-E | Reduces heat gain |
| Acoustic roof | Laminated acoustic DGU | For rain noise reduction |
Framing Systems
Aluminium
Most common. Powder-coated for corrosion resistance. Must be engineered for the span and wind load, and ideally thermally broken.
Stainless Steel
Stronger and slimmer profiles, allowing more glass and less metal. Use SS 316 in coastal areas. Higher cost.
Structural Steel
For long spans and heavy loads. Requires painting or galvanising and regular inspection.
Structural Silicone Glazing
Glass bonded directly to the frame with structural silicone, eliminating visible metal. Very clean look but demands precise workmanship and correct silicone specification.
Drainage: Where Most Roofs Fail
Water always finds the lowest point. If a glass roof does not positively drain, it will leak — eventually.
Design Principles
- Minimum fall — at least 3–5 degrees for glass roofs, more for larger spans.
- Continuous falls — no flat sections or reverse falls.
- Gutter sizing — Singapore's intense rainfall demands generous gutters and downpipes.
- Overflow provision — a secondary path for water if the primary drain blocks.
- Debris management — leaf guards on gutters to reduce blockage.
- Access for cleaning — design in a way to reach and clear gutters.
Sealing Methods
| Method | Description | Best For |
|---|---|---|
| Structural silicone | High-strength silicone bonded joint | Structural glazing, clean lines |
| Wet glazing | Glass set on setting blocks with gaskets and silicone | Standard roofs and canopies |
| Dry glazing | Compression gaskets, no wet silicone | Where future panel replacement is expected |
| Cap and bead | Metal cap over gasket | Traditional, serviceable |
Common Causes of Glass Roof Leaks
- Failed silicone — UV exposure and thermal cycling harden and crack silicone over 5–10 years.
- Blocked gutters — leaves and debris cause water to back up above the seal line.
- Insufficient fall — water ponds and eventually finds a path through.
- Movement — thermal expansion and building settlement open joints.
- Poor workmanship — inadequate surface preparation before silicone application.
- Wrong silicone — using general-purpose sealant instead of structural-grade.
- Failed gaskets — hardened compression gaskets lose their seal.
- Penetration leaks — poorly sealed fixings and anchor points.
Leak Repair Process
- Water test — apply controlled water to identify the exact entry point. Leaks rarely originate where the drip appears.
- Inspect joints — check every silicone line and gasket.
- Remove old silicone — cut out failed silicone completely; never seal over it.
- Clean and prepare — surfaces must be dry, clean and primed.
- Apply new silicone — structural-grade, correct bead profile.
- Check drainage — clear gutters and confirm falls.
- Re-test — verify the repair with another water test.
Glass Roof and Skylight Costs in Singapore
| Item | Specification | Estimated Cost (SGD) |
|---|---|---|
| Fixed skylight | Laminated tempered, up to 1 sqm | $900 – $2,000 |
| Glass canopy | 8.38 mm laminated, per sqm | $700 – $1,400 |
| Glass roof | 10.38 mm laminated, per sqm | $850 – $1,700 |
| Large span roof | 13.52 mm laminated, per sqm | $1,200 – $2,400 |
| Low-E roof glass | Laminated tempered + coating | +$150 – $350 per sqm |
| Silicone replacement | Per linear metre | $25 – $60 |
| Leak repair (typical) | Per job | $450 – $1,800 |
| Full roof replacement | Per sqm | $900 – $2,000 |
Heat Control: The Often-Forgotten Issue
A clear glass roof can turn the space below into a greenhouse. In Singapore's climate this is a serious comfort and cost issue. Options:
- Low-E coating — reflects infrared heat while transmitting visible light.
- Tinted glass — grey, bronze or green reduces solar gain.
- Laminated with solar interlayer — combines safety with heat rejection.
- External shading — louvres or a retractable awning above the glass.
- Double glazed roof units — significantly better thermal performance.
Maintenance Schedule
| Frequency | Task |
|---|---|
| Monthly (rainy season) | Clear leaves from gutters and check for ponding |
| Quarterly | Inspect silicone lines for cracking or lifting |
| Every 6 months | Clean glass; check fixings and gaskets |
| Annually | Full inspection; water test; check structural fixings |
| Every 5–8 years | Plan silicone replacement before failure |
Frequently Asked Questions
Is glass safe for a roof?
Yes, when laminated tempered glass is used and the frame is properly engineered. Laminated glass retains fragments if broken, so nothing falls.
How long do glass roofs last?
The glass can last 25+ years. Silicone seals typically need replacement every 5–10 years in Singapore's climate.
Why does my skylight leak?
Almost always failed silicone, blocked drainage or insufficient fall. Proper water testing identifies the exact entry point.
Can I walk on a glass roof?
Only if it has been specifically engineered for foot traffic — which requires significantly thicker laminated glass and is uncommon in residential installations.
How much does a glass roof cost in Singapore?
Between roughly $850 and $2,400 per sqm depending on glass build-up, span and framing system.
Design Your Glass Roof With Us
RH Glass Solution Pte Ltd designs, fabricates and installs glass roofs, skylights and canopies across Singapore, using laminated tempered glass and structural-grade sealing.
- Phone / WhatsApp: +65 8616 1337
- Email: rhglasssolution@gmail.com
- Website: www.rhglasssolution.sg
- Hours: 24 hours, 7 days