Spans in construction refer to how long a structural element, like a beam or a joist, can be before it needs support from something else, like a wall or a column. It's like a bridge – you can only make it so long before it needs piers to hold it up to support the intended load. Knowing the right spans is crucial for building safely and making sure floors and roofs stay strong and don't sag or collapse.
The spanning capacity of load-bearing members is determined by a combination of stress grades and timber sizes and product engineering. Span tables allow users to choose an appropriate size and stress grade to achieve spanning needs.
For simple construction, such as domestic construction, this can be determined from span table supplements in AS1684.2 and AS1684.3. Below we have included common product span tables for:
- Deck joists
- Floor bearers
- Floor joists
- Upper lintels
For other, more complex, load condition spans use our free Hyne Design software.