Expansion Calculator

This calculator allows you to work out the potential expansion of all our systems, together with the Branch leg / Expansion loop size that would be needed to cater for this expansion.



Pipe material

Change in length expansion / contraction (mm)

Pipe size

Minimum length bend / branch leg B (fig, 1 & 2) (m)

Pipe length L (m)

Minimum leg length expansion loop C (fig, 3) (m)

Temperature variation (°C)

Minimum width expansion loop
C / 2 (fig, 3) (m)


  • Change in direction (fig 1)

  • Branch (fig 2)

  • Expansion (fig 3)


All calculations are only given as a guide and this information should not be considered as replacing or superseding your duty of professional care with regard to suitability, design or specification. Glynwed Pipe Systems (trading as Durapipe UK) nor any other subsidiary of the Aliaxis Group accepts any legal responsibility for the content of these calculators.