What Is Mist Coating And Is It Important?

Mist coat is a term that is thrown around a lot when decorating but do you know what it actually means?

What Is A Mist Coat?

A mist coat is a thin, watered-down layer of paint applied to fresh dried, new plaster or drywall before you apply the finishing coats of paint. New plaster is very absorbent (which means it soaks up any moisture really quickly) which causes the topcoat to dry too quickly and unevenly. Starting with a mist coat will help the new plaster soak up the paint to create a bond between the new plaster and paint. For new plaster it is imperative that you start with a mist coat.

What If I Don't Apply A Mist Coat

Without a mist coat you're likely going to have poor adhesion between you paint and plaster. which can lead to the paint flaking, cracking and even peeling of in big sheets. It is vital that a mist coat is applied to avoid these issues.

How Do I Apply A Mist Coat?

Now we know what a mist coat is and why it's so important to apply. Lets see what the next step is. 

When painting new plaster, it's important to let the plaster fully dry and cure before applying paint. Generally, new plaster can take anywhere from 2–4 weeks to fully dry, depending on the thickness and humidity. To speed up the process you can increase air flow but opening windows, or use utilise your heating but use this gently. 

If painted whilst still wet, this would seal the surface and trap moisture in the plaster which can lead to the paint bubbling and peeling away.

What Paint Do I use?

You can either use a contract matt or use the paint you are using for your top coat but watered down. The rough guide for mist coats is 10-20% water added to the paint, but this is stated on the back of the can as this varies from product to product. The easiest way to do this would be to decant the paint into a scuttle and add the necessary amount of water.