Manufacturer reference installation - not a Windows Guy project.
A fixed window has no opening sash: the glass sits in the frame and only lights a room and frames a view. On European systems, fixed lites are normally paired with tilt-turn or casement units in one frame, so the fixed glass does the looking and the operable unit does the breathing.
How big can a fixed window be on a European system?
There is no catalog size grid for a fixed lite, so I do not quote one maximum. Size is set by glass weight, by the glazing depth the frame accepts, and by the shop drawing for your opening.
The provider catalogs I work from publish sash maxima only for operable units, and those are operable limits that I do not apply to fixed glass. The one fixed-panel figure published is 2,645 lb (1,200 kg), and it belongs to the fixed panel of two sliding door systems, not to windows. So for a window, I confirm the lite size on the drawing.
What does glass weight do to a fixed lite?
Weight rises with both area and thickness, so a taller, wider or thicker lite is heavier, and a triple-glazed unit carries three panes instead of two. That is arithmetic, not a catalog limit: the same opening in triple glazing is a heavier lite than in double. The weight decides what glazing support the frame needs and how the unit is handled on site, and I confirm both on the drawing.
What glazing can a fixed window take?
Each system publishes the thickest glass unit its sash or frame accepts, and the table lists those ceilings for the window systems I source. The value is glazing thickness, not lite size, and four of the nine values below are published for the sash or vent, so the fixed-lite thickness is confirmed per drawing.
| System | Max glazing thickness |
|---|---|
| MasterLine 8 (Functional vent) | 2.83 in (72 mm); Hidden Vent confirmed per order |
| MasterLine 10 (Functional) | 3.46 in (88 mm) |
| MB-79N (sash) | 2.48 in (63 mm) |
| MB-86 (AERO sash) | 2.76 in (70 mm) |
| Genesis 75 (triple) | 2.13 in (54 mm) |
| MaxLight (sash) | 2.68 in (68 mm) |
| Ideal Neo uPVC (triple) | 2.05 in |
| Clad Hidden Sash (XL glass) | up to 2.28 in (58 mm), double or triple |
| COR 70 Hidden Sash | 1.02 to 1.57 in (26 to 40 mm) |
Glazing options include double or triple glazing, tempered safety glass, laminated security glass, acoustic glass and solar-control coatings; see triple glazing for the thicker build. I do not give performance numbers here, because those belong to the specific assembly.
Can a fixed window look the same as the windows that open?
Yes, with hidden-sash variants, where the operable sash sits behind the frame so it reads like fixed glass. They exist on MasterLine 8 and 10 (Hidden Vent), MB-79N US, MB-86 US, Genesis SU, MaxLight Invisible, COR 70 Hidden Sash and Clad Hidden Sash. The matched look is covered on the hidden sash windows page.
How do I combine fixed lites with tilt-turn sashes?
Put the big glass in the fixed lite and the ventilation in a tilt-turn window beside it, or in an outward-opening European casement where the room needs the clearance. A pairing works when you follow three rules:
- Join the units at a mullion or transom, drawn on the shop drawing.
- Match sightlines so fixed and operable frames look the same width.
- Make sure each room has at least one operable unit, and confirm ventilation and egress requirements with your building department.
Does a fixed window count as egress?
No. A fixed window cannot serve as an emergency escape opening because it does not open. Confirm the rule with your building department, and see egress rules for tilt-turn windows for the operable companion.
What should I send to get a fixed window quoted?
Send the facts that set the glass and frame:
- The opening size.
- The glass specification you want.
- Any operable companions in the same frame.
- The frame color.
Use the quote form, the estimator for a budget range. Prices are not in this post; what drives them is in what aluminum windows cost.
FAQ
What is the difference between a fixed window and a picture window? Nothing in US usage: both mean a window that does not open. It is often called a picture window when it frames a view.
How large can a fixed window be? It depends on glass weight, glazing thickness and the drawing, so I do not quote a single maximum. The table above gives the published glazing ceilings; I confirm the size per drawing.
Can fixed and operable windows look identical? Yes, with hidden-sash variants, which put the operable sash behind the frame so it matches the fixed glass.
Do fixed windows need a warranty size check? Ask whether glass-seal coverage has a square-footage cap, since caps tend to land on large fixed lights. See European window warranty and service.