Joist sizes the wood boards used as floor joists generally range in size from no smaller than 2 by 4 inches to no larger than 2 by 12 inches.
Timber floor joist sizes.
Bci joists are specially constructed i joists with flanges made from strong versa lam laminated veneer lumber with oriented stranded board webs and approved waterproof structural adhesives providing outstanding strength and durability.
Southern yellow pine and douglas fir have high bending strength.
Hemlock spruce and redwood have medium bending strength.
Surveyors and structural engineers use data from tables below to help calculate the size of timbers necessary to give adequate support to timber floors.
Two by 6 inches is a joist size frequently used in both indoor floors and as deck joists.
You should check with your local building department for construction requirements in your area.
Joist span and spacing is set by your local building code.
These tables can help calculate whether floor joists are strong enough to support themselves and the load they carry without the help of any walls underneath.
Engineered wood products ewp span and size charts for bci joists.