I want to paint the outside of my house. It is currently bare sandstone. Do I need a primer to start with and how many coats if I do, what is the best primer and paint to use and also how many coats of paint.
A sealer/primer is definitely recommended. It is better to use a pigmented primer that acts as a sealer and also gives a good base coat for your colour. You then need two good coats of masonary paint. I would sugest using Dulux or Sandtex SMOOTH paint. Don't be tempted to go for cheap paint. It is false economy as it won't stand up to the weather and they don't have the same depth of colour. That should be good for at least five years, longer if you are not too exposed to bad weather.