Post and Sail Failure

Mainsailz was retained to provide advice to a Shade Sail contractor that had been requested to submit a quotation for a replacement for a fairly new waterproof sail that had filled with water (ponding) and collapsed during a storm.

The contractor advised that the damage to the sail and structure was the subject of an insurance claim and that an insurance assessor had already inspected the site and deemed the damage unrepairable.

The contractor was concerned that the original design may have been faulty and under engineered. Due to future liability issues he required a second opinion before committing to undertake a like for like replacement using the same fabric and posts as requested by the client.

From photos and plans provided by the home owner Mainsailz was able to ascertain the following:

  1. Fabric type
  2. Post size
  3. Post height (apron)
  4. Roof height (apron)
  5. Size of sail

Using a Sailmakers modeling program, Mainsailz was able to design a sail and post structure that would work on the site set out provided. Our clients concerns were rightly justified – the design showed the original structure that had only recently been installed, was always going to fail.  We concluded that it had been severely under designed without adequate fall to allow water run off and using incorrect fabric and posts for the project.

Our client took the advice on board and based their quotation on the revised design that would not come back on them in the future. The home owner also made a formal complaint to the QBCC regarding faulty building work.