A triple sliding window — often called a 3-panel or 3-lite slider — packs three glass panels into a single frame. What separates it from a standard two-panel slider is not just the extra pane. The third panel changes how much of the opening you can actually use, how the frame is built, and how much wall depth the unit needs. This guide walks through the configurations, the trade-offs, and how ALPES builds the same idea into its TS130 side-press sliding window.
A triple slider is really two different products wearing the same name, and the difference is entirely in which panels move:
| Configuration | Panels that move | Approx. clear opening | Best use |
|---|---|---|---|
| OXO / XOO | One | About one-third | Wide walls where one vent is enough |
| XOX (triple track) | Two | About two-thirds | Living rooms, cross-ventilation |
The appeal of a three panel sliding window is not just the view — though a fixed centre pane does read like a built-in picture window. The real gains are practical:
More panels means more tracks, and more tracks means a deeper frame. Industry guides commonly cite two-track frames around 50 to 70 mm deep and three-track frames at 100 mm and beyond; the exact number is a property of the system, not a rule you can read off the panel count. The deeper the track, the more wall reveal the unit needs, so the rough opening should be checked early — before the wall is built or the old window ordered.
The one ALPES figure we can state plainly: the TS130 side-press sliding window carries a frame wall width of 130 mm. That is the number that has to fit into your wall, and it is the honest answer to "how deep is this thing" for that series.
ALPES lists the TS130 with two arrangements: middle fixed + two sides movable (that is the XOX triple configuration) and one fixed + one movable (the two-panel build). So the "triple sliding window" idea is not something ALPES approximates — it is a published mode of the TS130. The real specification, as ALPES publishes it:
| TS130 parameter | ALPES published value |
|---|---|
| Aluminium profile | 6060-T66, 1.8 to 2.0 mm wall |
| Thermal break | PA66GF25, multi-chamber |
| Frame wall width | 130 mm |
| Glass sash / sash width | 55 mm / 75 mm |
| Track height | 53 mm / 31 mm |
| Hardware | German ROTO side-pressure system |
| Pulleys | 200 kg load-bearing |
| Locking | Eight-point |
| Sealing | Four-sided continuous |
| Mesh options | 80# / 40# S/S, anti-PM2.5 available |
Extended options ALPES offers on the TS130 include an inward-opening sash mesh, an integrated glass railing, and an anti-theft grille — useful when the triple slider sits over a low-height opening or a stair void.
Be careful here. ALPES does not publish a K-value for the TS130 sliding series. The thermal numbers in the ALPES catalogue belong to other opening types: AW90 at K=1.3 (tilt-and-turn passive window), C120 at K=1.6, and C116 at K=1.7 (both casement). Those are useful as a frame of reference for how the brand engineers thermal breaks, but they are not the sliding window's whole-unit value. The honest answer is that a sliding window's thermal performance depends on the glass build you specify, and you should request the calculated value for your exact configuration rather than borrowing a casement number.
Before you ask a factory for a quote, pin down these points so the reply is comparable across suppliers:
| What to decide | Why it changes the window |
|---|---|
| Wall width | Sets panel count and track depth |
| View vs ventilation | A bigger fixed centre means more glass, less opening |
| Climate | Drives glass build, Low-E and inert gas |
| Screen need | Some tracks reserve a channel for mesh |
| Wall reveal | Must clear the frame wall width (130 mm for TS130) |
A 2 panel sliding window is the workhorse: about half the width opens, the frame stays slimmer, and it costs less to make. Choose the triple when the wall is genuinely wide, you want air from two sides, or a fixed centre pane serves the view. Choose the two-panel when the opening is modest and budget or wall depth is tight. Neither is "better" — they answer different briefs.
Put these in the request so the factory cannot answer vaguely:
ALPES manufactures from a 100,000 m² base across Foshan and Zhaoqing, Guangdong, and ships complete window and door systems in full containers. That direct path is what lets a alum sliding window like the TS130 be quoted as a bill of materials for your project rather than a shelf item. Send the checklist above and request the thermal and size values for your exact build — the numbers that belong on the order are the ones calculated for your glass, not the ones printed in a brochure.
