Each shed location is unique and as a result it is necessary to determine the use (building class) and site wind speed to determine the correct specification for that shed.
Sheds intended for Cyclonic or Snow regions are required to consider these extreme conditions in their design.
ShedSafe accredited shed sellers provide the following information on quotes.
- Wind Region The location of the shed will determine which wind speed region will be applied to ensure that your shed withstands weather conditions.
- Importance Level is determined by what you intend to use the shed for, and is crucial for ensuring that your shed complies with the Building Code of Australia.
- Terrain Category is determined by what surrounds the proposed site of the shed.
- Topography factor refers to whether the shed is to be placed atop a hill, midway along a slope or a flat site at sea level
- Shielding factor is determined by whether the proposed site is shielded by permanent structures.
- Site Wind Speed which is expressed in metres per second, ie. 41 m/s
Your ShedSafe accredited supplier will provide you with a quotation that will show a site wind speed m/s (metres per second) and the values of the factors above that were used to calculate that wind speed.
The site wind speed is a rating on the strength of your shed. Check the site wind speeds on the quotations you receive. Generally, the lower the site wind speed, the less steel is required and the cost will reduce.
Other points to be aware of:
- If your shed supplier is NOT constructing the shed, you should speak with a licensed builder and or building certifier to determine the suitability of the quoted specification for the intended site. This may require a site visit in some circumstances. Don’t get caught out by buying a shed that won’t pass council.
- Do not accept quotations from shed suppliers that refer to “w” values i.e. W41 as these codes are obsolete.
- Quotations from shed suppliers that show wind speeds N2 or C2 or similar, are nominations applicable for houses and some small class10a sheds. Ask the shed seller for a quote with the site wind speed expressed in metres per second.
- Always look for the ShedSafe logo which is your assurance that the shed design and engineering is based on current design codes.