Why sliders suit Mumbai
Flats here are compact and most have a balcony. A hinged door swinging inward loses floor space and fights the curtains; swinging outward it fouls the grill or the parapet. A sliding panel moves in its own plane and projects nowhere.
Sliding systems also carry large panels comfortably, so you get more glass and more daylight per opening than a hinged equivalent of the same width.
Track configurations
Two-track. Two panels, one behind the other. About half the opening clears. Slimmest frame, lowest cost, the most common arrangement.
Three-track. Three panels, roughly two-thirds clears — or two panels plus an insect screen running in its own track.
Four-track. Four panels in pairs, so most of the opening clears. Deeper frame and more cost, but the right answer on a wide balcony.
Anything beyond that, and you want slide-and-fold.
The sill is a drained channel
Worth saying plainly because it causes most sliding door complaints. The bottom track is designed to collect water that gets past the panels and drain it back outside through weep holes.
When those silt up, the track holds water instead, and it eventually crosses the inner upstand onto the floor. It is not a leak in the usual sense — it is drainage that has stopped working, and clearing it takes minutes.
Rollers
The carriages take the whole panel weight on a small contact area. Two rules follow:
- Specify the roller load rating for the actual glass weight, including any future upgrade.
- If you reglaze a slider to a heavier sealed unit, upgrade the rollers at the same time.
Ignoring the second is the usual reason a young door has become heavy to move. See door service and repair.
Security
A large glazed panel that slides needs more than a latch:
- multi-point hook locks that engage into the frame at several points
- anti-lift blocks, so the panel cannot be levered up off its track
- laminated glass, which holds together and buys time
Materials
uPVC insulates better and costs less; aluminium gives slimmer sightlines and spans wider openings, which on a full-height balcony opening is often what decides it. Both are fabricated here to the surveyed size.
The window-height equivalent is covered under sliding windows; for the comparison across all door systems, see door types.