Does anyone know the ratio for lime render / plasters Scratch Coat Base Coat Finish Coat Help much appreciated.
I love lime render, primarily because it goes off slowly so you can lovingly rub it down to a smooth surface. Plus the breathability and flexability benefits. It's not like mixing cement, you're are best to use a lime putty, especially on heritage buildings or natural construction. So that means buying in ready mix. As long as you keep it wet and covered with plastic then it'll last forever. Actually older is better, although you should use it within a few weeks if it has fibres ( hair /hemp/straw) because they do rot in the lime. It also benefits from a good 10 min in a mixer to get it nice and plastic so it is workable. Having said that... Lime Green do a good powered mix. I've used their finish coats on top of ready mix. https://www.lime-green.co.uk/products/lime-render
You can also make a lime putty by mixing hydrated (hydrated not hydraulic. Don't get these mixed up) lime with water until it gets to a toothpaste consistency. Cover the top with a couple of inches of water and let it mature for 6 weeks or longer. Then mix it with sharp sand. 3sand to one lime. Add horse hair for the first coat.
I've always used 3-1 and then a 5-2 on any finishing coats. A million ways to do things with lime. Alot of people use marble dust for their finishing coat etc
It's usually weaker coats with cement/sand render, but on 3 coat lime work a spread I know who does a lot of lime plastering uses 3/1 sand/lime on the first 2 and then 1/1 or even 1/2 sand/lime on the top coat depending on the type of sand used,
Buy it in a bag, a lot easier nowadays,& Lime Green top coat is a darn nice product to use. A lot of peeps use Adfill fibres or Fibremesh 150 instead of horse hair nowadays, you can buy lime plaster with fibres added,called Fibrelime. https://www.lime.org.uk/products/lime/plasters-renders/fibrelime.html http://www.stastier.co.uk/nhl/guides/plasnhl.htm
Thanks for the replies, I'll probably buy some ready mix by the sounds of it. I don't think we have any suppliers in Derby so I'll have to look further afield.
I use http://www.womersleys.co.uk/ They are based in Dewsbury but delivery is on a pallet carrier at a flat rate so the distance is irrelevant. You need a drop off where the stuff can be wheeled on a pallet trolley from the kerb. I you are rendering then you need to get a move on, it needs to be frost free for 6-8 weeks while it cures .... and it cures slower when it is colder!