Quick answer: Spider glazing is a frameless glass facade in which each toughened glass pane is held at its corners by stainless steel “spider” fittings bolted through holes in the glass, instead of being set in an aluminium frame. The spiders are fixed to a support structure behind (steel tubes, glass fins or tension cables), and the joints are sealed with weather silicone. The result is an almost all-glass wall, ideal for showroom fronts, lobbies and double-height entrances.
How spider glazing works
A spider glazing system has four main parts:
- Glass panes: toughened or toughened laminated glass, with countersunk holes drilled near each corner before toughening.
- Routels (bolts): stainless steel fixings that pass through the holes. Articulated (swivel) heads let the glass flex slightly under wind without stressing the hole edges.
- Spider fittings: stainless steel brackets with one, two, three or four arms. One spider typically holds the corners of up to four neighbouring panes.
- Support structure: the backbone that carries wind and dead load to the building.
Joints between panes are filled with weather silicone, giving a smooth, flush glass surface.
Types of support structure
| Support | Look | Typical use |
|---|---|---|
| Steel tube (MS painted or SS) | Visible vertical posts behind the glass | Showroom fronts, entrance walls |
| Glass fins | Almost invisible, all-glass | Premium lobbies, display fronts |
| Tension rods or cables | Very light, technical look | Large atriums, feature walls |
| Truss | Architectural steel feature | Very tall or wide spans |
Glass fins and cable systems look lightest but need more engineering and precise installation.
Spider glazing vs other glass facades
| Spider glazing | Structural glazing (SSG) | Capped curtain wall | |
|---|---|---|---|
| Frame visible outside | No | No | Yes |
| Frame visible inside | No (only support structure) | Yes, aluminium frame | Yes |
| How glass is held | Bolts through the glass | Structural silicone | Pressure plates |
| Transparency | Highest | High | Medium |
| Best for | Lobbies, showroom fronts | Full building facades | Offices, budget facades |
Where spider glazing works best
- Car and bike showrooms, where the vehicles inside are the display.
- Hotel and office lobbies and double-height entrances.
- Retail flagship stores wanting a clear, premium front.
- Staircase walls and atriums in commercial and residential buildings.
- Canopies, using toughened laminated glass.
Local example: the Chandra Hyundai showroom on Avinashi Road, Chinniyampalayam, Coimbatore, has a spider-glazed frameless glass front with an ACP fascia above.
Materials: what to specify
Glass
- Toughened glass at minimum; toughened laminated for high panes over walkways and for canopies.
- Heat-soak testing reduces the small risk of spontaneous breakage from nickel sulphide inclusions.
- Thickness is set by panel size and wind exposure. Large showroom panes are commonly 12 mm or more, or laminated build-ups, as worked out by design.
- Holes, countersinks and edge polish must be done before toughening. Toughened glass cannot be drilled or cut afterwards.
Fittings
- SS 304 for most inland sites like Coimbatore, Tiruppur and Erode.
- SS 316 for coastal sites (Chennai, Kochi, Thiruvananthapuram, Thoothukudi), pool areas and industrial zones. It resists rust staining far better.
- Check the finish (satin or mirror) and the quality of the articulated routels.
Support structure
- Mild steel structures must be properly primed and painted; galvanised or stainless steel is better in humid and coastal areas.
- Anchors into the slab or beam must be designed for the load.
Heat, glare and privacy
A large spider-glazed front facing west will let in a lot of heat and glare. Options:
- Solar-control or tinted glass.
- A deep canopy or ACP fascia projecting above the glass.
- Internal blinds that do not touch the glass.
- Orienting the main glazed front north or east where possible.
Doors in a spider glazed front
Most showroom and lobby fronts need an entrance. Frameless toughened glass doors with patch fittings and floor springs sit naturally within a spider glazed wall. Points to plan:
- The door’s top transom and side panels must line up with the spider grid.
- Floor springs need a recess cut into the floor before the final flooring is laid.
- Handles, locks and door stoppers should be chosen for the daily traffic.
- Consider an automatic sliding door for high-footfall entrances.
Maintenance
- Clean glass regularly; salt and dust deposits show quickly on clear glass.
- Inspect weather silicone joints every year, ideally before monsoon.
- Check fittings for loosening, corrosion or tea staining.
- Look at hole edges for any chips or cracks.
- Repaint mild steel support structures when the paint shows wear.
Planning a spider glazing project
- Confirm the opening and structure. The slab, beam or foundation must be able to take the support structure’s loads.
- Decide the support type based on the look you want and the span.
- Fix the glass grid. Panel sizes affect thickness, weight, handling and cost. Very large panes look impressive but need heavier glass and more careful installation.
- Choose glass and fittings for exposure: tint or solar control for west faces, SS 316 near the coast, laminated where people walk below.
- Plan the details: door positions, the top junction with the fascia or slab, the base detail and drainage.
- Measure accurately after the support structure is fixed, because each pane is drilled and toughened to order.
Advantages and limitations
Advantages
- Maximum transparency and a premium look
- No aluminium frame lines on the face
- Works for tall, double-height openings
- Individual panes can be replaced
Limitations
- Needs a well-designed support structure
- Glass must be made to exact size with drilled holes; no on-site adjustment
- Sun-facing fronts need heat and glare control
- Joints and fittings need periodic inspection
How Cladex helps
Cladex Elevations installs spider glazing, structural glazing and ACP fascia, and the Chandra Hyundai showroom front in Coimbatore is an example of our spider-glazed work. Our engineers measure the opening, choose glass, fitting grade and support structure for your site and exposure, and set out every item in the quote.
WhatsApp us a photo of your front or lobby for a free, site-measured spider glazing quote.