We're building a single storey rear extension on our property. We've had the drawings done by an architect but are doing the build ourselves. We've got to the point now where we are ready to put in the steel support beams but have an issue with understanding the size of the pad stone on the drawings.
Steel sizes - twin 203x133x30 kg/m about 4.3m long.
It then says to place on 225x225x2cdp PC pad stones ..... but we've no idea what cdp stands for??? Can anyone help??