[RE-wrenches] Vertical wall mounted arrays

[North Texas Renewable Energy Inc]

Wrenches
I have a customer building a new 2 story home with a great S-SW exposure but only to the wall that makes up the entire end of the house. The owners want no ground mounted array to preserve the hot, dry, rocky yet beautiful landscape.
This will be a pretty straightforward wall mounted, perfectly tilted pair of >30 foot arrays. The big glitch is that they plan on finishing the entire house with natural limestone, Austin stone it's called 'round here.
My concern is this; to extend the mounting "standoffs" 6"-7" beyond the rock face and still keep the weight of the array from putting excessive strain on the attachment lag bolts, I need something with a diagonal rib or some other means of bracing the horizontal standoffs supporting the top of each array.
Mounting a brace every 48", 3x16" centers, could do the trick but turn into a lot of extra stone work and cost for the mounting BOS. I would prefer fewer but stronger mounting brackets. Bolting completely thru the wall studs is not an option.
The actual array tilt and rail hardware will be the Pro Solar Roof track tilt up kits which should hold well for the vertical pulling force as well as it does for its normal horizontal dead-weight strength.
Any suggestions would be appreciated. This will be the first wall mounted system I have tried so I want a no-regrets design even if it's a bit overdesigned.
thx
Jim Duncan
North Texas Renewable Energy Inc
817.917.0527
ntrei at earthlink.net
www.ntrei.com 
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