Rebar steel vs grp

[jfg]

I am building a timber frame garage next to my brick built garage.

I need to know if people have use grp and steel and which is better suited or more preferable.

the garage is 2.7 metres wide by 5.5m long.

it is going to be dense block up to 3 blocks high which is going to support timber frame of garage and retain the garden. it will be tanked obviously.

i've seen on tv where they only run a few grp lengths through the concrete pad for houses as opposed to steel square mesh grids.

any advice gratefully received.

 

[sxturbo]

What's cheapest?

I've only seen and done with rebar and lasted well.

I've not seen the grp stuff tbh

 

[JohnD]

Are you talking about reinforcing the raft?