On 4/24/2014 5:46 AM, Mick Dowling wrote:
> 
>
> What I haven¹t been able to establish is why in Australia stud spacings
> settled on 18², and have been for 130 years at least that I know off.
>
> 
My impression is that Australian woods have greater strength than do 
American woods, especially softwoods typically used in framing.  I 
wonder if that additional strength might not have provided adequate 
resistance to deflection, thus allowing the use of less material that 
using 18" centers over 16" centers would provide.  Most old-time 
carpenters that I have known were concerned about the strength and 
durability of their work and equally concerned about economy.  For some 
reason, it seems to me that today's framers know more about codes than 
about reasons that underlie them.  Old-time carpenters would have 
scorned modern, fast growth, 1-1/2 x 3-1/2 two-by-fours as suitable only 
for outhouses and temporary structures, I suspect.

Bob Hutchins
Temple, TX, USA