# Forum Home Renovation Pergolas, Gazebos, Strombellas & Rotundas  Gazebo Rafter Size

## chalkyt

I saw some interesting replies to a post in August re Verandah Rafter Sizes. I have a similar situation re timber sizes and some expert advice/interpretation of span tables would be useful. At this stage I am throwing the proposed design to a local builder for review (for a fee), but it would be good to get some forum wisdom as well. 
The project is a free standing hexagonal gazebo with 2400 sides making it a 4800 span diagonally. Timber will be F7 TP. The posts will be 90x90 with knee braces at the top for stability. Perimeter beams are planned to be 190x45 although span tables suggest that 140x45 would do but I don't want the structure to look too "skinny" as we are in a N3 wind area.. 
My confusion is with rafter sizes. The rafters will be at about 24 degrees, joined in the centre of the Gazebo by a Demac six sided bracket top and bottom. The bracket looks a bit like an asterisk and is made from 5mm steel. Some of the replies to the August post inferred that the greater the angle, the more you can "uprate" the span. In my case does this mean that the six rafters at 24 degrees running from the posts and joined in a star shape can span the 4800? My thoughts are to use 140x45 rafters (I don't imagine that 90x45 would do the job although I understand that 120x45 is sometimes available). 
Can such a rafter structure be used unsupported in the middle? I have an inclination to tie two of the diagonal posts together with a horizontal beam, plus a couple of struts from this beam to the rafters. This wouldn't happen on all three sets of diagonal posts, just one set. i.e. one set would be joined by this truss like arrangement with the other four rafters spanning from the centre to the outside beams (about 2500 at 24 degrees). 
Any thoughts and comments would be welcome.

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