How to Paint Exterior Brick
Painted brick has a style all its own and is seen more and more as decorating trends shift. If you are planning on painting brick, make sure to patch any cracks or ruts that are often caused by ivy breaking through when the bricks are outside.
Step 1 - Clean the Brick
Begin with your pressure washer. It’s the simplest way to clean exterior brick.
Set the washer to somewhere between 1500 and 2000 pounds per square inch. Don’t go higher than that pressure range when you wash the bricks, as too much force might damage the mortar. Add soap to the stream for more difficult efflorescence and mildew deposits. The primary point of the wash is to clear any dirt, grime, and loose paint—nothing else.
Once the washing is completed, allow the brick plenty of time to fully dry. This will take a few days at least because brick is a porous material that traps moisture.
WARNING: The pressure washer can be dangerous. Follow all the product instructions and always aim the stream of pressurized water away from yourself and others.
Step 2 - Remove Loose Paint and Fix Mortar
Remove all loose paint that is left behind on the brick face or else it will cause early chipping when you eventually apply your coat. Use a hand scraper to get the larger pieces.
Do not use a wire brush. It is easy to get carried away and gouge the brick or leave ruts in it using a wire brush.
Step 3 – Sand the Brick Smooth
Sand the brick smooth using either a palm or circular sander with a minimum 80 grit paper.
Then, repair any missing and damaged mortar. You can use a premixed acrylic mortar patch that enables you to prime and paint as soon as it is dry. Alternatively, you can mix a powder mortar yourself, but this will take a few weeks to dry before you are able to begin priming.
Step 4 - Prime Brick
Always use a high-quality acrylic or latex masonry primer for painting exterior brick. Remember all mortar as well as brick should be primed. Prime those places where efflorescence and mildew occurred first so that you can give an extra coat if needed. It typically takes 1-2 hours for the coat to dry. Give time for the primer to dry completely before moving on to painting.
Step 5 - Caulk and Seal
Caulk any area that can let water in, even an opening as small as a 1/16 inch. This includes doors, windows, trim, and chimney caps. Be sure to use 100-percent acrylic caulk and a foam backer rod for bigger cracks. You may need to repeat this process after 3-5 hours.
Step 6 – Clear the Dust
Before beginning, remove all the dust that’s come to rest on the brick face with a brush or vacuum.
Step 7 - Paint the Brick
When choosing exterior house paint, elastomeric or 100-percent acrylic latex are the two best options. Apply two coats in order to achieve its highest durability.
For best results, brush and roll the brick as you would any other wall. Just be sure to use at least a 3/4 inch roller or thicker to make sure every nook and cranny gets filled with paint.
Edward Kimble, a professional painter and author of Interior House Painting Blog, contributed to this article.