Dave,
You might only need more joists beneath the roadbed. I use them every 16" and support blocks every 8" between the laths. You might even need more for heavy snow regions. The laths are cedar 1-1/2" deep by 5/16" thick and have held up beautifully here in the wet NW. I do prime each lath. Remember too that the concrete backer board weighs quite a bit and if their is insufficient benchwork support it too will sag.
Using material as you're thinking should work too but you lose the whole advantage of the ladder track method, namely easy to form flowing curves without the need to cut everything to shape. If I was going to do it that way I'd be more inclined to do as the guys in Canada on the IPP&W do and use 2x PT or cedar material screwed down although Mark's method sounds plausible as well.
Whatever method you use don't skimp on materials. Shortcuts usually lead to doing everything over and costing much more in time and money than doing it right the first time.
You might only need more joists beneath the roadbed. I use them every 16" and support blocks every 8" between the laths. You might even need more for heavy snow regions. The laths are cedar 1-1/2" deep by 5/16" thick and have held up beautifully here in the wet NW. I do prime each lath. Remember too that the concrete backer board weighs quite a bit and if their is insufficient benchwork support it too will sag.
Using material as you're thinking should work too but you lose the whole advantage of the ladder track method, namely easy to form flowing curves without the need to cut everything to shape. If I was going to do it that way I'd be more inclined to do as the guys in Canada on the IPP&W do and use 2x PT or cedar material screwed down although Mark's method sounds plausible as well.
Whatever method you use don't skimp on materials. Shortcuts usually lead to doing everything over and costing much more in time and money than doing it right the first time.
