The design of windows follows key engineering considerations, with the most important specification being the ability to bear wind load. The vertical members, such as the transom and mullions in the center of the window, bear the force of the wind and must be strong. When evaluating the weight of aluminium sections for doors and windows, it’s important to understand how these structural components perform under stress. The frame, on the other hand, is not a structural member but serves secondary functions like water drainage and fixing hardware. For example, aluminium door weight is designed to balance strength and practicality, ensuring both durability and ease of operation.
Key Engineering Considerations in Window Design
1. The most common specification followed in India is ASTM standards.
It may be noted that the weight of windows is not a key specification in these standards, as performance and functionality are prioritized. The rating of Tostem Windows is as follows:
Specification of Tostem Windows as per ASTM Standards |
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| Performance Parameters | Tostem WE+ Series | Tostem Grants Series |
| Wind Load (E330) | 1600 Pa | 2000 Pa |
| Water Tightness (E330) | 240 Pa | 300 Pa |
| Air Tightness (E283) | 10.7 m3 / h·m2 | 10.7 m3 / h·m2 |
| Sound insulation | 25 DB (6 mm glass) | 25 DB (6 mm glass) |
Note: The window hardware must also pass the same standards as window members.
2. The process for calculating Wind load is as follows:
A. Check Structural stability following National Building code 2016_ IS 875 Part 3
B. Calculate structural strength by two methods: – Section Thickness as per Performance & Design
I. First by calculating deflection & compare with the actual moment of inertia of the profile.
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II. Second is the physical testing of full-size Window samples.
- Testing is carried out in a recognized test lab to verify how the window will behave when subjected to actual wind loads.Tostem test reports are available for customer reference.
- Testing also confirms that small accessory parts—such as the rail on top and bottom of the frame, the lock on panel, and other small accessories—do not fail under high wind loads.
3. Typical weight of Tostem Windows
Tostem UPVC windows are designed for high performance with a focus on structural integrity rather than weight. Unlike fabrication companies, Tostem follows a mass manufacturing style, where window weight is not typically specified for each quote.
| Design | WE + Series | Grants Series |
| 2T2P Slider Door (2400*2400 mm) | 20 kg | 26 kg |
| 2T4P Slider Door (4500*2400 mm) | 48 kg | 95 kg |
| 3T3P Slider Door (3000*2400 mm) | 36 kg | 45 kg |
4. Tostem Design Follows Lean Principles:
The emphasis is on simplicity, eliminating waste, and enhancing customer value. The key focus is ensuring the product performs its function well, backed by ASTM standards in design and testing. Weight does not equal performance, as illustrated by how cars like the Ambassador were overtaken by newer models like the City or Civic—showing that newer innovations can outperform heavier predecessors.
5. The Section Thickness in Tostem Windows is not Uniform:
As it depends on the strength requirement. For example, the jamb profile has a minimum thickness of 1.4 mm because it is attached to the wall, while the hurricane bar has a much higher section thickness of 8 mm, far superior to any competitor.
This approach helps ensure the strength and durability of the window frame, while also addressing the weight of aluminium sections for doors and windows. The section thickness in Tostem is not uniform. It is dependent on strength requirement. In the drawing below the jamb profile has minimum thickness of 1.4 mm as it is attached to wall. In reverse, the hurricane bar has a section thickness of 8mm which is far higher than any competitor.
| Section Thickness as per Performance & Design | |||
| Bottom Profile | Jamb Profile | Inner Meeting Style | Outer Meeting Style |
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FAQs
What are the key engineering considerations in window design?
The main consideration is the ability to bear wind load. Vertical members like transoms and mullions support the wind load, while the frame handles water drainage and hardware fixing.
How do you calculate wind load for windows?
Wind load is calculated based on structural stability (National Building Code 2016) and tested using full-size window samples in lab conditions to ensure performance under wind pressure.
Is the weight of windows an important specification?
No, the weight of windows is not a primary specification. Performance factors like wind load, water tightness, and air tightness are more important.
What is the typical weight of Tostem windows?
The weight varies depending on the window size and series. For example, a 2T2P Slider Door weighs around 20 kg, while a 2T4P Slider Door can weigh up to 95 kg.
How does Tostem achieve performance standards without focusing on weight?
Tostem focuses on engineering, design, and testing to meet performance standards, not on weight. The product must function efficiently, meeting ASTM standards.
