Hi Timbeal,

Ooops! - I hadn't spotted that this frame has a single 25' clear span bay between the bents (cross frames). That's really a tad too much and it might have been better to split this span into 2 bays of 12.5ft. For future reference 16ft is approaching the maximum length per bay and more usually bay lengths are in the range 8 - 12 ft. This frame is very "empty" and as such it has very little in the way of second lines of defence for load shedding should there ever be a major component failure.

Given that the frame has a fairly low pitch roof and a fairly light roof covering and that the gable ends are to remain open (the sides as well ?) then I would anticipate that this frame will most likely be vulnerable to wind damage. Frame design is not all about beam sizing to satisfy dead loads.

Regards

Ken Hume