Painting New Plaster
What You Should Know Before Painting New Plaster
Recently plastered walls should be left to dry thoroughly before the painting should begin ,if it was just a re skim over the walls or skimmed plaster partitions or dry lined walls ,then the drying times should really be around 3 days ,in a well ventilated room .If you have a had a new backing plaster ,such as a browning or bonding coat applied first ,then a coat of skim ,drying time for painting could be closer to 7 days ,and 6 weeks before a wall paper can be hung due to the lime and salts still present .
If you paint before all of the water is removed you will effectively be sealing in the water and it will need to find another way out . You may even find the emulsion may not stick properly to damp plaster also .The damp patch will be present until you repaint over the stain anyway ,maybe needing a stain block or undercoat to cover it over .
Painting New Plaster
When you do finally start to paint the new plaster you should ideally start with a what is referred to as mist coat first ,so what is a mist coat ?you say . A mist coat is a coat of emulsion that has either been thinned dopwn ,by adding a small amount of water ,or an emulsion that has already been thinned down for the purpose of painting new plaster .You can go to any diy store and pick up paint for new plaster costing around £18 a tub but generally a cheap brand of white matt emulsion with a touch of water added is all thats needed .
Mix the paint at a 50/50 ratio ,making sure it is well mixed before starting .Remember that now the paint is much thinner there will be more splashing so put down those dust sheets before you start .
So Why Use A Mist Coat ?
Theres a number of reasons why you use a mist coat when your painting new plaster ,the first one being that the new plaster is so dry that it will immediately suck in and dry any moisture added to it ,including the moisture in your paint ,making it hard to roll and leaving a hard or thick line at the edge of your roller every time you stop to reload the roller with paint ,making it very difficult to spread the paint and ultimately get a good finish to your walls .Applying a mist coat will also help to seal the new plaster ,stopping any top coats of paint from peeling .