Clear annealed — the default I push back on
Cheap, bright, easy to replace. Breaks into daggers. Does almost nothing for heat or noise. I allow it on small, high, low-risk panes when the budget is genuinely ugly. A full-height picture window in clear float is how you get a parent on the phone after a cricket ball. When a contractor says “just glass,” this is what they mean.
Toughened
Heated so it is several times stronger, crumbs into dull cubes if it goes. Bathrooms, low sills, doors, anything a child can run at — this is my floor. You cannot cut it after it comes back from the plant, so the size has to be right. It still lets heat and sound through like ordinary glass of the same thickness. People buy it thinking they bought insulation. They bought safety. Say that out loud in the meeting.
Laminated
Two plies, plastic in the middle. Breaks and hangs there instead of coming into the room or onto the podium. Ground-floor bedrooms. Openings over a pavement. Anyone who has had a break-in conversation with their society. The interlayer also takes a bite out of road noise and most of the UV that fades the teak. Costs more. Light is a shade lower. For a lot of Mumbai bedrooms on a main road this is the pane that changes the week, not the frame brand.
Double glazing — the one people confuse with two sheets in a track
Factory unit: two panes, sealed gap, air or argon. Dust in a slider gap is not a DGU. I have opened “double glass” quotes that were two loose sheets. Heat slows down when it is a real unit. Noise drops more if the inner pane is laminated. The frame has to be deep enough. If the edge goes milky in year twelve, you replace the unit, you do not wipe it. West glass you sit next to — this is where I spend. A north store the size of a suitcase can wait.
How I mix glass options for aluminium windows (uPVC too)
You can toughen one leaf of a DGU. You can laminate the inner and toughen the outer. Write the millimetres. “Good glass” on a tender is how 5 mm float shows up on a 2.4 m pane.
A map I actually use: high small panes — clear or toughened. Anything you can fall through — toughened or laminated. Sleeping on a road — laminated, often inside a double unit. West glass by a sofa — DGU, Low-E if they will pay.
Rough 2026 glass-only bands, not the whole window: clear Rs 150–300 a sq ft; toughened Rs 250–500; laminated Rs 400–800; a DGU Rs 600–1,500+. Saving two thousand on glass on a big aluminium opening is how you hate the room.
Edges chip if the crew is in a hurry. A chip on toughened can become a crack in August for no polite reason. I look at the beads. A draught around clever glass is still a draught.
Frequently asked questions
If you had to pick one glass for the whole house, what would you pick?
I would not. A toilet and a west living room are not the same pane. That is the whole point of talking about window glass types instead of “good glass.”
What’s actually the safest for a low window the kids run past?
Toughened, or laminated if you also care about it hanging in the frame when it goes. Clear annealed there is me being careless.
We hear traffic all night. What should we put in the bedroom?
Laminated. Better, laminated inside a double unit. Thickness helps. The frame logo does not.
Is toughened the same as insulated?
No. I wish people would stop selling it that way. Toughened is safety. Heat is a DGU or Low-E conversation.
The contractor said “double glass.” How do I know it’s real?
A factory unit with a sealed edge, not two loose sheets in a track with dust in the middle. I have opened both. They are not cousins.
Ground floor, we worry about someone breaking in. Laminated?
Yes. It hangs there and takes time. Toughened crumbs and is gone. Different job.
Can we mix types room by room?
You should. That is how glass options for aluminium windows (and uPVC) are meant to be written — as a make-up, not one word.
Bathroom — clear or frosted, and does it have to be toughened?
Toughened, often obscure. Wet floor plus dagger glass is a story I do not want in my week.
We already have the opening. Can you cut toughened to fit if we change our minds?
No. It is cut before it goes to the plant. Measure like you mean it.
Does laminated stop the furniture fading?
It blocks most UV. Teak still ages, just slower.
What does glass even cost, roughly?
Clear Rs 150–300 a sq ft, toughened Rs 250–500, laminated Rs 400–800, a DGU Rs 600–1,500+. That is glass, not the whole window. 2026 numbers, they move.
How long before we are doing this again?
The pane lasts. Accidents and failed DGU seals are what end it. A chip on toughened is not a “we will watch it” situation on a high opening.
Bring a room list. Star Windows will mark where clear is fine and where it is a lawsuit waiting for a tennis ball. I would rather argue about millimetres now than about a shard later.