Bolt placement for braces

[nesbit]

Hi,

I am constructing 2 braces out of treated pine to hang off the purlins (which is hardwood of some sort) so i can store my timber off the floor. I was wondering if someone could recommend which option to use for the fixing of the coach bolts (pink dots), or any other advice.

[bitingmidge]

I think the best advice that you could get is that timber purlins are designed for supporting thin sheet metal, or more correctly I suppose they are designed for uplift loads imparted by thin sheet metal.

I'd do some serious engineering investigation to see what impact the sort of load you are planning will have on the structure.

When you've got that sorted, the detail will probably be irrelevant.

Cheers,

P

[nesbit]

What i will do is take a photo of the structure tonight do give a better picture of what i am looking at fixing the braces to.

[joe greiner]

Subject to verification of adequate purlin strength for your loads and span, the bolts should be placed at mid-height of the purlins, except at the ends of the span, where they should be placed above mid-height. Combination of many factors here: Near the centre of the span, mid-height placement lessens reduction of purlins' bending strength; near end supports, bending strength is less important, but should be above mid-height so as not to compromise shear strength. In general, bolts (centre lines) should be at least 4 times bolt diameter from the free edge in the direction of force.

Joe