Fixed glazing — the cheapest square metre of glass
Fixed glazing is the cheapest square metre of glass you can buy. No sash, no hinges, no handle. The frame is narrower, so more of the opening is glass.
The catch is cleaning. If the outside of a fixed unit is not reachable from a balcony, terrace or the ground, plan for that before ordering, not after.
Corner glass
Corner glass, sold under names like "glass corner", means two insulated glass units meeting at 90 degrees with no post between them. The units are step-cut so the outer pane overlaps, and the joint is sealed with structural silicone. Almost always fixed.
Two things to know. First, the corner is the thermal weak point: with a standard corner post the insulation is continuous; in a post-free corner it relies on the sealant only. Second, external blinds and roller shutters need special corner systems — standard guides will not work. Polish manufacturers quote roughly 50 to 80 percent more than a comparable window with a post.
Floor-to-ceiling units
Floor-to-ceiling units run into fall-protection rules. In Poland the sill must be at least 0.85 m above the floor, otherwise you need a balustrade or a fixed lower section with safety glass. Your country has its own numbers — check them before you send dimensions.
One more limit: the glazing rebate. A typical 70 mm uPVC frame takes units from 6 to 42 mm, up to 49 mm with an adapter. Thick acoustic or laminated units for big spans need to fit.
HST or PSK for terrace doors
Both slide. That is where the similarity ends.
PSK, tilt-and-slide, uses a standard window profile with special hardware. You tilt the sash, then pull it towards you and slide it sideways along the fixed pane. It also tilts for ventilation, which HST cannot do. The hardware is visible from inside. The threshold is a full frame height, around 5 cm, because the tracks are screwed to the front of the frame; some systems offer a lower threshold of about 2 cm as an option. Sizes are limited, and the sash has to be pushed by hand along its whole travel, so a heavy PSK is a workout.
HST, lift-and-slide, is a different construction. Turning the handle lifts the sash a few millimetres onto rollers, after which even a very heavy leaf moves with one hand. Lowering it seals the door. The threshold sits almost level with the floor, which matters for wheelchairs, prams and simply not tripping. Sizes go far beyond PSK: in aluminium and timber a single leaf can weigh up to 400 kg. The frame is deeper, so the wall opening and the floor build-up must be planned for it.
Price: PSK costs roughly what a large window costs. HST is a premium item — expect a significant step up.
We supply HST in uPVC, aluminium and timber. Maximum sizes depend on the profile system and the glass weight, so send the opening size and we check it before quoting. The easiest way is the configurator — you pick the opening type on the drawing and we verify the sizes with the quote.