Hi there, Any advice on this would be very welcome, I am rendering a brick garden wall. I have coated the wall with a watered down mixture of cement sand and PVA additive, that has created a nice rough surface for the render to bond to. I am using a mix of 1:1/2:4, cement/lime/sharp sand. I am applying the render with a metal plastering trowel. The render goes on fine, but after a bit it seems to sag in areas like its pulling away from the wall, one of the sections just peeled off. I have tried dryer and wetter mixes, but have the same problem. I noticed as I was smoothing out the render the trowel was bringing the water to the surface, thought that might be the problem so tried using a wooden float, but again the render started to bulge and fall off. I am applying the render approx 1cm thick.