Grating Deflection Calculator

Grating Selection


Grating Type

Grating Size

Load Type

Enter Load

Recommended Load: 1.5-100KPA/KN (Varied along Span Length)

Enter Span (mm)

Recommended Span Length : 200-2000 mm

For GratEX® and MoultrEX® rectangular gratings, the support span is along the length of apertures. For GridEX® gratings, the support span is along load bars.


Span Length (mm) Load Mid-Span Deflection (mm) Span/Deflection
1. AS/NZS 1170.1 shows the minimum design live load.
2. Design loads for walkways – not less than 2.5kPa uniformly distributed load (AS 1657).
3. Combinations of actions for serviceability limit state and safety load factors can be found in AS/NZS 1170.0.
4. The loads represented are for STATIC LOAD CONDITIONS at ambient temperature.
5. Deflections for impact loads or dynamic loads will MULTIPLY the deflections shown by 2.
6. Long term loads will result in added deflection due to creep in the material and will require higher factors of safety to ensure acceptable performance (ANSI/ACMA).
NNon-Stocked Item.
CCommonly Stocked Item.
Important Note:
It has been identified that data might differ from previously published information. It is the responsibility of the user to conduct their own due diligence. This data is only relative to Treadwell products and will not guarantee the same performance as other similar products.