Thread: Joist sizes
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Ian Stirling Ian Stirling is offline
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Default Joist sizes

Tony Bryer wrote:
On 08 Dec 2006 18:03:27 GMT Ian Stirling wrote :
Doubling the height of the joists quadruples the stiffness.


Quadruples the strength, increases the stiffness by 8. Stiffness is
proportional to depth^3 , so just going from 150 to 175 high joists
increases the stiffness by nearly 60%


Err - yes.