Will 2" x 8" tongue and groove sheathing over log rafters spaced 4' apart support this much weight? I'm interested in building a house with straw bales for roof insulation and 6" of living turf on top (over a rubber membrane). Any structural engineers or knowledgeable carpenters out there? Thanks!
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*The depth of the plant growth media is between two to six inches on extensive green roof systems. The weight specifications for these roofs are 16 to 35 pounds per square foot, so it is important to use a light-weight soil media. “You almost need to be an engineer when designing these types of soil mixes because you are working with so many materials of different sizes, weights and measures*
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If you're going to be just using this soil for growing turf, two inches would be the most soil you need, so your 2" x 8" tongue and groove sheathing over log rafters spaced 4' apart to me seems over engineered depending on the size of the logs and over engineered is probably the way to go.
Carpenter & Joiner