casement windows for home use are the ones that swing. Hinge on the side, stay or friction arm so the wind does not slam it, multi-point lock if you want the gasket to actually meet. Outward is what we fit most. Inward eats the room and fights the curtains. I have watched a client discover that after the pelmet was up.
Mumbai, specifically
aluminium casement windows Mumbai still have to deal with rain hitting the head of the frame, and with grills, AC trays, and flower pots that were not on the interior drawing. Open the sash in your head before you order. If it hits the split AC, we are not doing casement there. Sliding it is, and we stop arguing.
Ventilation is why people want them. A bedroom that can throw the whole opening at a cross-breeze in September is a different room from one with a 50% slider. The close is usually tighter too, if the frame is square and the lock is not a single cheap latch on a ground-floor window. I will not do ground-floor casement on a mystery lock. I have had that conversation with more than one society secretary.
High floors: the stay has to be rated. Wind on the 14th is not a gentle evening. Cheap stays droop. Then the sash hangs tired and the lock misses and someone says “aluminium is bad.” The stay was bad.
Hot west face: write a thermal break or do not be shocked in May. Plain metal casement looks sharp and conducts like anything else.
The shapes we actually cut
One leaf, side hung — bedrooms. Two leaves meeting — wider halls if there is swing room both ways (there often is not). A top-hung flap over a kitchen counter so you get air without a full door into your face. Casement beside a fixed picture pane when the view is the point and you only need one bit that opens. That is most of the residential list. “Designer” is usually a colour and a handle. Ask about the stay.
Money
Straightforward aluminium casement still sits in a band around Rs 450–1,200 a sq ft. Add the break, better glass, named hinges — Rs 850–2,500 and I have gone over. Hardware is where the cheap quote hides. I read that line.
Fitting, because this is where casement fails
Plumb. If the frame is out, the sash sags and you will be lifting the handle with your shoulder in month eight. Hinges take weight; do not let someone use the same screws they use on a light slider. Seal the head. Rain runs down an outward leaf and looks for a gap. Before the crew leaves I open it fully, latch it, and look for light at the corners. If I can see daylight, we are not done.
A bit of spray on the hinges once a year. Clear the drainage. Coastal — rinse the salt off the section. Same as any aluminium, plus I wiggle the stays because those are the bits that quit.
If the furniture is tight, do not force casement because a reel said it seals better. If you sleep with the window cracked on a noisy road, casement plus a proper gasket and heavier glass is worth the swing. Mix rooms. We do sliding in the hall and casement in the bedrooms more weeks than we do a single type throughout.
Frequently asked questions
What’s the difference between this and a sliding window, in real life?
Slider: half the hole, no leaf in the room. Casement: almost the whole hole, and a sash that needs somewhere to go. I start with the sofa, not the catalogue.
Outward or inward — what do you usually fit?
Outward. Inward fights the curtains and the pelmet. I have watched that discovery happen too late.
We have a grill. Can we still do casement?
Only if the grill lets the sash open. Send a photo of the grill and the AC tray. I have said no more times than yes on cluttered Mumbai elevations.
Ground floor — are these safe enough?
With a proper multi-point lock, yes. With a single cheap latch, I will not do it. Society secretaries have strong feelings and they are not wrong.
We’re on the 14th floor. Anything we should worry about?
The stay. Wind is not a gentle evening up there. Cheap stays droop, then the lock misses, then someone blames aluminium.
Will it leak in the rains? Our last windows did.
An outward leaf catches water at the head. If that detail is sealed and the frame is plumb, it behaves. If someone rushed the head, July will tell you.
How much should we budget?
Plain ones, roughly Rs 450–1,200 a sq ft. Break, better glass, named hinges — Rs 850–2,500, sometimes more. If hardware is a blank line, ask.
Can we do sliding in the hall and casement in the bedrooms?
That is most of our weeks. Do not force one type through the whole flat.
Do they need a lot of looking after?
A spray on the hinges once a year, keep the drainage open, rinse if you are near the sea. I wiggle the stays when I visit because those quit first.
Will this help with heat?
A tight close helps. A thermal break and decent glass help more on a west face. The hinge type is not an insulation product.
Colours?
Powder coat. That part is easy.
Why Star Windows for this?
I will walk the room before we cut casement aluminium windows. I would rather lose the casement and keep the dining chair than send a leaf into furniture.
Star Windows will walk the rooms before we cut. Call, WhatsApp a video of the opening, or come to the showroom and work a sample stay with your own hand.