Thickness, application and 2026 rates
| Application | Thickness | Glass rate (₹/sq ft) | Notes |
|---|---|---|---|
| Shower screen, fixed panel | 8 mm clear | ₹130 – 190 | Plus ₹3,500–12,000 for hardware per cubicle |
| Shower enclosure, hinged door | 10 mm clear | ₹170 – 240 | Hinges must be rated for the leaf weight |
| Office partition, framed | 10 mm clear | ₹170 – 240 | Aluminium framing priced separately |
| Frameless glass door | 12 mm clear | ₹220 – 320 | Patch fittings and floor spring add ₹18,000–45,000 |
| Balcony or staircase railing | 12 mm toughened laminated | ₹320 – 480 | Laminated is mandatory where a fall is possible |
| Kitchen cabinet shutter insert | 5 – 6 mm | ₹150 – 260 | Often lacquered or frosted |
| Frosted, acid-etched or ceramic-printed | Add-on | +₹60 – 180 | Done before toughening |
Hardware frequently exceeds the glass cost. A frameless 12 mm office door with floor spring, patch fittings and a lock is usually ₹35,000–70,000 all-in.
Why everything has to be decided before toughening
Tempering locks the glass into a stressed state. Cut it, drill it or grind an edge afterwards and it shatters instantly into thousands of pieces. This changes how the job has to be run.
- Measure on site after the civil work is complete and the walls are plumb, not from the architect’s drawing. A 6 mm out-of-plumb wall over 7 ft is normal in a Mumbai flat and it has to be in the glass dimension.
- Every hole for a handle, hinge, patch fitting or lock is dimensioned on a fabrication drawing and signed off. A missed hole means a new panel.
- Edge finish is specified up front: ground for hidden edges, flat polished for exposed ones, bevelled where the edge is a feature.
- Cut-outs for switches or sockets in a glass splashback need a minimum distance from the edge, typically one and a half times the glass thickness. A cut-out too close to an edge will break during toughening.
- Allow two to three weeks from approved drawing to delivery. Toughening is a batch process and Mumbai fabricators run to a queue.
Spontaneous breakage and heat soaking
Nickel sulphide inclusions are microscopic impurities in the glass that expand slowly after tempering and can break a panel years later, with no impact. It is rare but it is real, and where a panel is overhead or very large the consequence is serious.
- Heat-soak testing holds the toughened glass at around 290°C for several hours, which makes vulnerable panels fail in the factory instead of on site. It adds roughly 10–18% to the glass cost.
- Specify it for overhead glazing, skylights, large frameless panels and anything over about 3 sqm.
- For a shower screen or a small partition the risk is low enough that most clients decline it, which is a reasonable decision made knowingly.
- Laminated toughened glass is the other answer: if a panel breaks, the interlayer holds the fragments in place. It is mandatory for railings and balustrades.
Mumbai considerations
- Access. A 12 mm frameless door panel at 2,100 × 900 mm weighs about 55 kg and must be carried up, not lifted in a passenger lift on its edge. In older buildings with a dog-leg stair, confirm the panel can turn the landing before ordering.
- Salt air. The glass is unaffected; the hardware is not. Within 2 km of the sea, specify SS 316 fittings rather than SS 202 or 304. The price difference is modest and the difference in five-year appearance is not.
- Society rules. Balcony glazing usually requires society permission and sometimes a municipal view. Confirm before fabricating a panel that cannot be modified.
- Silicone. Use neutral-cure structural silicone. Acetic-cure silicone corrodes metal fittings and smells for days in an enclosed bathroom.
Care, life and BOQ wording
- Squeegee shower glass after use. Mumbai water leaves mineral deposits that etch the surface permanently if left for months.
- Apply a hydrophobic glass sealer to shower screens at handover and annually thereafter; it turns a weekly chore into a monthly one.
- Expected life: indefinite, absent impact. Hardware is the part that wears.
- BOQ: “12 mm clear toughened glass to IS 2553, heat-soak tested, all edges flat polished; cut-outs and holes per approved fabrication drawing; site measurement after completion of civil works.”
- BOQ: “All fittings in SS 316 grade. Neutral-cure structural silicone only. Rate inclusive of site measurement, transport, hoisting and installation.”
Specification summary
| Property | Specification |
|---|---|
| Standard | IS 2553 safety glazing |
| Thickness | 8 mm showers, 10 mm partitions, 12 mm frameless doors |
| Heat soak | Specify for overhead and panels over 3 sqm |
| Laminated | Mandatory for railings and balustrades |
| Edges | Flat polished on all exposed edges |
| Hardware | SS 316 within 2 km of the sea |
| Rate | ₹130 – 480 per sq ft, glass only, ex-GST |
| Critical rule | No cutting, drilling or grinding after toughening |
Frequently asked questions
Can toughened glass be cut to size on site?+
No. Any cutting, drilling or edge grinding after tempering causes the panel to shatter. All dimensions, holes and cut-outs must be finalised on a fabrication drawing before the glass goes into the furnace, which is why site measurement after civil works matters so much.
What thickness do I need for a shower enclosure?+
Eight millimetre for a fixed screen, 10 mm where there is a hinged door, and 10 mm throughout if the enclosure is tall or wide. Six millimetre is sold for showers and it flexes noticeably; the saving is not worth it.
Is heat-soak testing necessary?+
It is worth specifying on overhead glazing, skylights and large frameless panels, where a spontaneous failure would be dangerous or very expensive. On a domestic shower screen most clients decline it, and that is a defensible choice provided it is a decision rather than an omission.
Why does the hardware cost as much as the glass?+
Because a frameless system transfers the whole weight of the panel through a few fittings, which therefore have to be engineered. A floor spring for a 55 kg door, patch fittings and a lock together are frequently ₹25,000–50,000. Under-specifying here is how doors start to drop within a year.
Will toughened glass shatter on its own in a Mumbai bathroom?+
It is extremely unlikely. The known cause is a nickel sulphide inclusion, which is rare, and heat soaking removes most of that risk. What is far more common is damage to an unprotected edge during installation, which then fails weeks later. Insist on edge protection during the fit-out.