Have you ever walked into a paint shop to buy paints, and the ONLY thing you know about paint is only a brand name and the colour you want to buy? And it is only later, after you've made all the effort to hire a painter (or to paint yourself) that you realize that the paint you bought isn't working out as well as you'd like?
One thing I realized after looking at articles and press releases from paint companies, is that their recommendation is always centred around their own products. While it is comfortable to stick to a famous brand name, I've found that sometimes the best results aren't achieved by using the most famous or most expensive paints. I don't see why I should pay a premium just to subsidise their marketing and advertising costs.
There are some general guidelines on the TYPES of paints that can be used for each area or application in a house. By using these guidelines, you can make an informed choice on the paints that you use in your homes, and not just blindly follow a brand name.
1. What type of paint should you get for outside walls?
The paint specialists call these 'exterior architectural paints', what it means is that these paints are designed using pure acrylic resins because this type of chemicals are resistant to the damaging effect of the sun's rays. However, these paints are also designed to be fungus resistant, and this is done by using fungicides to kill off the algae or moss that grows in all those damp places. So if you do have some left over outdoor paint from your paint job, please don't use it inside your house where a child may accidentally eat the paint chips from the wall.
2. What if I see cracks on my walls?
Cracks are usually caused by poor quality cement (i.e. too much water was used), or because the wall was painted before the concrete had fully set. If you see these defects, the first thing you'll need to do is to remove all the defective paint from that wall. The most common solution is to use an acrylic crack-bridging paint on the wall. What that means is that a soft, flexible paint is used to cover the crack. This doesn't mean that the crack is gone, it is merely covered up by the paint, and it won't show up on the surface. This prevents water from entering the cracks, which can cause further damage to the concrete. One drawback about many crack bridging paints is that it is soft, so dirt can easily stick on it. This is why this type of paint should be used as an undercoat, not as the topcoat for the concrete. Without a topcoat to protect it, the crack-bridging paint can easily pick up dirt and becomes black.
3. I am seeing bubbles or fungus on the walls inside my house
This is caused by water seeping into the concrete, either from outside, condensation from air conditioning, or even damaged water pipes inside the wall. The continuous inflow of water carries salts and other contamination from inside the concrete, and brings it up to form bubbles of water that is trapped underneath the paint. This moist paint becomes an ideal place for fungus to grow.
The source of water must be removed, either by repairing the pipe leakage, remove the cause of the water seepage and use a solvent based primer or a styrene-acrylic paint to prevent water from entering the concrete. It is usually best to use this paint on the outside wall, as the water is stopped at the source, rather than after water has soaked up the concrete like a sponge. Styrene-acrylic paints also have a stronger smell, so that is one more reason to use it on the outside walls. However, styrene-acrylic paints do need a topcoat, because the very thing that makes it effective against water, also makes it sensitive to sunlight. The paint will become yellowish if it is exposed to sunlight.
Just by following these tips, you can free yourself from blind brand loyalty, and dive straight in to the actual type of product you'll need. This will lead to $$$ savings, while maintaining the kind of properties that you were looking for.
• Use pure acrylic or acrylic paints for outdoor walls
• If there are cracks, use a crack bridging paint or elastomeric paint as the primer
• Use a stryrene acrylic paint as a primer if you have a water seepage problem
