Hi, I'm a DIYer in my spare time. I've picked up most things, including plastering (Mainly skimming), which I'm quite good at. A room I'm going to replaster - walls / ceiling, the plaster has blown from behind the radiator and I've pulled it off, the rest is sound. I did similar in another room and I struggled with the cement render when patching up. Cement doesn't seem as easy to handle as plaster. Can anyone give any advise on the mix / ratio, and how best to approach it? Should I use PVA 1st? I'd rather use a cement render than something like hardwall as I want to do some rendering outside this year and its good practise. Thanks in advance!
The trick here is NOT to use rendering sand, you need to use soft washed sand, mixed at a true 5.1 ratio with a good splash of Feb mix, then when putting it on the wall use a fiberglass/wooden float, it will stick to a metal one.
Thanks, that's very useful! I was using sharp sand as I thought that's what you're meant to use, but I will give a go with soft wash as suggested at the weekend, that was easier to handle when I built a wall. Thanks again!
Hang on. Could someone enlighten me please. When rendering, the trick is to NOT use rendering sand ??? Mr. HandyAndy - Really
I know it sounds stupid, but having failed miserably at trying to repair a large area of render years ago, using rendering sand bought in small bags and having it fall off the wall all time, I sort the advise of a expert, who laughed at me and said you will never get that sand to stick ( great for floors, rubbish for walls), he advised soft washed sand, instant success.
If you have trouble laying it on with a trowel, the pooh slinging method is brilliant if messy, this video shows an outside wall, but no matter -
i would definitey pva first half water to pva. Normal building sand 5:1 or 4:1 will make a good mix. Do not make too wet. It will go on just like plaster, (infact although it is rarely done nowadays you can plaster a wall and get it totally smooth with soft sand / cement). Hardwall is also ok, but definitely PVA area first and leave to dry before hand if using hardwall or tough coat. Good luch - Greg the plasterer.