Knowing when a calculation is not a design
The difference between a screening number and a compliant design, and where professional review genuinely has to enter.
The engineering question
The calculator gives a number and the drawing is ready. What has actually been established, and what has not?
Why there is no calculator here
This topic is about the boundary between arithmetic and a sealed design. No calculation can settle it, which is precisely why it needs publishing.
Engineering review required
This topic supports professional engineering work; it does not replace a sealed design. The result depends on site data, the governing standard and engineering judgement, and should be confirmed by a competent engineer before it is built.
References & standards
- BS EN 1990 — basis of structural design
- ACI 318 — scope and intent of the building code
- Institution of Civil Engineers — Code of Professional Conduct
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