WOODWORKING QUIZ for 1 July 04

[Ralph Jones]

Good Evening Friends,
Using Douglas fir floor joists of 2 x 10 timbers. What is the allowable clear span for them set on 16" centers?

Respectfully,

[journeyman Mick]

What's the "F" rating of your douglas fir? Sorry but in Australia you can't use rule of thumb methods anymore for sizing your framing, and in this litigious day and age you'd be a fool to do so. Follow all the rules and if perchance something goes wrong then you won't be the one to get sued (it'll be the certifying engineer or the company that wrote the manual or the timber grader or supplier etc etc)

Mick

[Ralph Jones]

Hey Mick,
In our case it would be the Western Wood Products Association who would get the blame.

Respectfully,

[Kev Y.]

OK Ralph. now you have us curious.. what is the allowable clear span with 16" centres!!!

Kev

[Ralph Jones]

Good Evening Friends,
According to the Western Wood Products Association here in America, the allowable span for a 2 x 10 Douglas fir, laid out on 16" centres is 16' 9" clear span. Personally, I still prefer to have a beam in the center as I feel there is too much bounce on a floor of that size.

Thank you for your support.

Respectfully,