Can a large window opening ship as one assembly?
Yes. Multi-unit combinations are joined in the factory and delivered as a single assembly, so a wide opening arrives complete rather than as parts to align on site. The joining mullion is 1 1/8 inches (28 mm) at every height grade up to 13 feet; only the internal reinforcement changes.
Why factory joining changes the site work
A wide opening assembled on site is a jigsaw: every joint has to be aligned, sealed and squared by whoever is standing there, in whatever weather. Joined in the factory, the assembly arrives as one piece with its joints already made under controlled conditions, and the crew sets one unit instead of building one.
The joint, by height
The sightline does not grow as the assembly gets taller, which is the part specifiers usually want confirmed before they draw it.
| Window height | Joining mullion |
|---|---|
| up to 9 ft | 1 1/8" (28 mm) |
| 9 to 11 ft | 1 1/8" (28 mm) |
| 11 to 13 ft | 1 1/8" (28 mm) |
The mullion is the same width in all three grades. What changes with height is the internal reinforcement, not the sightline.
Where the limits are
Larger assemblies mean heavier assemblies, and both the crate and the lift have to be planned for. Oversized units and structurally glazed assemblies take longer than the standard production figure, and we say so before you commit rather than after.
For openings beyond what a joined window assembly suits, the commercial window wall range runs to 65 ft.
Send the opening schedule with the elevations. Whether an opening is best served by one joined assembly, several units and a structural mullion, or window wall is a question about the structure around it, and we would rather answer it on your drawings than in the abstract.
Source: Joining mullion widths and height grades per lib/big-openings.ts, from the manufacturing partner’s published configuration details.
Other questions
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- What U-factor do I need for my climate zone?
- What is a thermal break, and does it matter?
- Tilt and turn or casement: which should I specify for a US project?
- What does NFRC certification actually tell me?
- Can imported windows meet Florida HVHZ requirements?
- What documentation should a window supplier give me?
Still the wrong question for your project?
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