INTRODUCTION
Many sheds are not strong enough to support PV systems. Ideally, the roof frame should be examined as part of a site inspection. Furthermore, tilt-leg systems require the roof frame to be checked by a registered structural engineer.
BUILDING CODE
Sheds are Class 10a (non-habitable) structures under the Building Code of Australia. Sheds with a floor area greater than 10 m2 require a building permit.
STRUCTURAL SUITABILITY
Many sheds have been constructed without reference to the building code, or without a building permit. In comparison with dwellings, sheds have a greater risk of being structurally unsound, or have little capacity to withstand higher loads. Commonly, small sheds have minimal triangulation in their roof frames. Therefore, caution and care should be exercised prior to installing PV systems on sheds.
LOADS CREATED BY PV SYSTEMS
As a rough guide, a flush mounted system doesn’t increase the load on the roof frame very much. In contrast, a tilt-leg system can almost double the load on the roof frame. This is why the roof frame needs to be checked by a structural engineer.
CHECKS
Prior to installing a PV system on a shed, installers should confirm the following:
- The shed complies with the building code
- The shed was constructed with a building permit
- The roof is trafficable
- The frame is capable of withstanding the higher loads created by the PV system
MEASUREMENTS
The following assessments and measurements should be made:
- General condition of the frame (rust, borers)
- Batten material, size, gauge (thickness), span and spacing
- Rafter (truss or frame) material, dimensions, span and spacing.
For Further information
For further information contact Sunlock on 1300 655 554 or order@sunlock.com.au.