A simple couple of questions guys ... we are about to make up the shuttering for the raft for our detached garage. I have spare scaffolding boards or can use the timber sitting ready to be put together for the garage frame. They give me options of a depth of 225mm or 150mm. The cost of the extra ready mix concrete is minor as most of the cost is in the delivery of the one load. The only reason I'm thinking of the greater depth is to give me more scope for fixing the frame down to the raft - i.e. longer fixings. Any thoughts?

Talking of fixing the frame to the raft I am planning to use resin fixed threaded bars. But can I simply push the bars into the wet concrete?

Your advice will - as always - be much appreciated.

Kind regards, Jonathan

Personally I would use express nails, much easier than threaded bar.

Does the threaded bar need to be stainless or anything? If galvanized do you need to get it in the right lengths?

When I built garages on rafts we use thickened up edges, 225 x 400 with the slab as 125mm, the whole thing monolithic.

While the concrete was still wet we would place engineering bricks round under where the frame was going tight against the shuttering. Build the frame, end day one after the weekend put up frame, clad, build roof, third dat tile it. Frame can be fixed through holes in the bricks, or we would push holding down straps in beside the bricks at 2m c/c. We always stained the cladding before fixing.

I preferred mesh to fibres.