barry de swardt
Hi Satbir, The sand should be the builders choice. Some like building sand, some like plastering sand and some old school ones like a sharp sand and building sand mix. Ratio will be the same for all options 3:1. Make sure to add a stabilizer to the mix (SBR or similar). Remember that the main reason plaster "blows" is water ingress. So an edge should never be exposed.
