Painting exterior walls, especially masonry, render, or brick, is something I do on a regular basis as a decorator. I thought I’d take the time to sit down and write a quick guide for anyone who is thinking about carrying out this type of work. I’ll keep it brief and simple.
Ask any decorator and they will tell you that prep is the most important part of any job. This is especially true when painting exterior walls. To prep a job like this, you should first remove any loose or flaky paint with a good quality scraper.
Imperfections such as holes, cracks and contours can be filled using Toupret Masonry filler. On a smooth wall you can fill as normal, then sand down until smooth. On a textured wall, it is often better to blend the filler in when wet, using a paintbrush.
Chalky or unstable masonry on your wall should be primed using a good quality stabilising solution. The one I use is Zinsser Peel Stop, which is water-based, can be recoated after a couple of hours, and creates the perfect base
Moss and algae needs to be treated to stop it from coming back or bleeding through your finished paint. You can pick up a treatment online which you apply to the affected area a day before you’re due to paint the wall, then just allow it to dry.
Click here for a more detailed guide on how to prep an exterior wall.
Choosing your Paint
There are a few different things to think about when choosing the best paint for an exterior wall. I’ll give you the best options based on my experience and let you decide. A couple of things I would say, is breathability is important when it comes to masonry paint. You do not know if your render contains lime, which always needs to breathe. Plus, using a breathable paint helps to prevent trapping moisture inside your wall.
This is the best masonry paint on the market for a few reasons, but it isn’t cheap! Available online for over £20 per litre, Emperor Paint uses hydrophobic technology which makes it water repellent. So, not only will your exterior wall remain VERY waterproof, but dirt will not stick to it and the wall will look cleaner for longer.
There are other benefits too. It is breathable, and it is also heat retaining!! So, if you paint the walls on the outside of your home with this paint, you will save money on your heating.
There’s more; because of the technology in the paint, you are only going to need to paint your exterior walls every 25 years!!
This is the best of the standard trade masonry paint in my opinion. Very breathable, self-cleaning, easy to apply and looks great! It leaves a very flat finish, which is perfect because imperfections on your exterior wall will not be highlighted.
Oil-Based Masonry Paint
Oil, or pliolite-based masonry paint can be used in weather conditions which wouldn’t suit water-based paint. The other advantage is stains will not bleed through your paint finish (which can be a problem on garden walls and sandstone windowsills). My two favourite pliolite products are Johnstone’s Stormshield and Wethertex PP77.
The beauty of multi-surface paint is they can be used on anything. Masonry, timber, and uPVC, to name a few. This means you can stick with one product for all your exterior decorating, rather than swapping around.
Painting your Exterior Wall
Your prep is done, you’ve chosen your paint and now you’re ready to apply it. This part is quite self-explanatory really. Cover windows and doors before you start. Cover the floor with dust sheets. Then get set up.
I like to give my paint a mix before starting to ensure all the dye is evenly distributed within the material. I can also gauge the viscosity of the paint and decide whether to dilute it slightly to help ease of use.
Get yourself a stiff paintbrush and a long-piled roller. Cut in around the edge of your wall and then roll off the larger areas. Work on one section at a time to keep a wet edge. Don’t worry too much if you notice the odd imperfection. They often only show-up after your first coat when painting. Just allow the paint to dry, fill anything you’re not happy with, spot-prime, then apply your second coat.