foundationframingshed
Will this work for a 10 x 8 plastic resin shed –
Surface is 3/4 OSX 4×8.
Thanks.
Call in a pro.
This site can help with a lot of problems found in and around the home, but in some situations a problem cannot be diagnosed and solved effectively on the internet. Some problems just have to be looked at, and inspected before a proper solution can be proposed.
Comment converted to answer
Personally, I would dig the topsoil out from under the blocks—preferably down to mineral soil so that almost all of the concrete is buried. This makes less of a step up for wheeled equipment and less space for critters and weeds to grow underneath. I put mine very close to the ground on concrete blocks with slots for 2 inch wide lumber and concrete screws through the joist into the block to keep the wind from lifting it up:
The kind of concrete block you are using is plenty strong, though I don't see anything to keep your shed from moving, for example from strong wind, heavy rain, or leaning livestock.
The strength of the joists is the next weakest link in this design. Some more support in the middle could be overkill, but it is unlikely to be so.
Best Answer
What's the purpose of the two blocks in the center? Unless they're support a beam, they only effectively support the individual joists they're under. I would't use them. Worst case scenario they cause bulges in your floor.
The metal angles are also unnecessary. The fasteners you use to connect the joists (galvanized 20d nails or 3" coated screws), along with the floor sheathing, are adequate.
Finally, ask yourself whether you actually need the pyramids. Your PT lumber is rated for ground contact, and raising a shed that high makes for access challenges. You'd probably need to build a ramp at least 4 feet long. I've built two such sheds at my homes and simply rested the 2x4 floor framing on a washed rock base. If you do that, lay housewrap or poly sheeting under the floor sheathing to protect it from excess moisture.
I don't know what "cross members" are, but blocking isn't really necessary for an 8' span, in my experienced opinion.
Otherwise, I think you have a good plan.