Gary Cavie Wrote:
Hi,

Could anybody who has access to the regs for unsupported timber span
sizes, give me an idea as to what size timbers I need for a floor? It
will be 3300mm between supports, spaced at 400mm, and will be used for
a
shed / workshop (no particularly heavy equipment, just desk / chair /
electronics workbench etc).

Floor on top will be 18mm bitumenised OSB, with insulation between the
joists.

If I increase the spacing to 600mm, does that make much of a
difference?

Thanks for the help

Gary

The "old" way to do it, and in imperial, is half the span ( in feet )
plus an inch,
so for instance a 12' span would be half 12 = 6, plus 1 = 7, so 7 x 2
joists. That would be at 16" centres.
I know there are all sorts of regs/charts/tables etc but this is a
useful rule of thumb.


--
Nick H