After reading your post some questions come to mind . 1: will you have any shade if not you will have some expansion. it will get hot in LV as you know. 2. if you are going to use USA OR Aristocraft Track then u will need to leave some small gaps as you go and not use any jointer screws at that location and add jumper wires. 3.you say you are using composite wood. if you mean partical board don't use it after a good down pour or two you will not have much left. 4. if your using plastic composite you will need add more supports then planed to prevent sagging. 5. as far as securing your track to the boards yes but 1 screw every 4 foot will do. I have been using stainless steel #4 x 5/8 just to hold the track with some play. You may need 3/4 long screws with plastic . .
Dave
The head is gray, hands don't work , back is weak, legs give out, eyes are gone, money go's and my wife still love's Me.
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