Fix House Paint Discoloration

Keeping your home beautiful inside and out is a big job. Paint will only last so long even under the best conditions. When it comes to the exterior of your home, wind, dirt, precipitation and sun can all eat away at the color and protection. Here’s how to diagnose and fix house paint discoloration: causes and cures.

Water-Soluble Extractives

Some woods, while beautiful to look at, contain extractives that give it the color. These chemicals can leach from the wood and discolor adjacent paint. They will dissolve and leach from the wood due to everyday water and rain outside your house. They run down walls and as the water evaporates, a red-brown stain is left behind.

Repair: Good painting practices should fix house paint discoloration. Use a water-repellent preservative on your wooden architecture before you stain or prime it. Oil-based, stain-resistant primers will work best when working with wood containing the extractives.

Blue Stains

Blue stains on your walls can be a bit jarring when they first show up. This is normally a microscopic fungus on your walls that typically affects sapwood. If the walls are in a water-prone area, moisture will help the fungus thrive.

Repair: Before you attempt to repair the area, clean it thoroughly with household bleach until the discoloration is removed. Then purchase a water repellent preservative from your local paint store. Look around the area for the cause of the water that is feeding the fungus. Look at your eaves, roof angles and trees for potential culprits. Pooling and running water can help the fungus grow, so make sure you correct those issues before painting again.

Repair: To remove the stain, apply household bleach and use a scrub brush to remove the discoloration. Paint on water repellent preservative. Once it’s allowed full dry time according to the manufacturer’s instructions, paint the area.

Iron Stains

Houses built with nails to attach siding, wood or trim are at risk for iron stains. You will notice rings and dripping of a red-brown stain around nail heads. Many home builders and those providing wood repairs have switched exclusively to galvanized or non-corrosive nails preventing this issue.

Repair: Any nails causing these stains will need to be countersunk, caulked and spot primed before they can be painted to match the home. Depending on the amount of stains, you might need to replace wooden elements. If you are unsure of the repairs, consult with a professional before proceeding.

Fix House Paint Discoloration from Mildew

Wherever there is water, there can be mildew. It’s not exclusively bound to humid or hot climates. Mildew is made up of fungus that stains houses black, green or other colors. It’s most common to develop mildew outside your home, but it can lurk indoors too. When you inspect your home before or after winter, look specifically behind trees or shrubs where there is little air movement and potential water pooling.

Test: To see if you are dealing with mildew, use a drop or two of household bleach on the area where the discoloration is happening. Mildew will disappear from sight after a couple minutes. If it does not disappear, it’s more likely another kind of stain.

Repair: Any big box home repair store will carry mildewcide. Purchase this and use it as directed on the package. It can also be used to prevent further breakouts if you have a mildew prone area outside.

Chalking

Paints are not meant to last forever. One sign that you are due for an exterior paint job is chalking. This is when the pigment is released from the paint due to break down. It ultimately looks like a layer of chalk or powder on the surface.

Repair: When you are working on an exterior that is chalking, you are likely looking at a whole exterior paint job. Since this is a big undertaking for a novice, it’s a good idea to consult a pro before you decide to take on the project alone. If you do decide to attempt it on your own, you’ll want to prepare the surface appropriately to avoid future chalking. Scrub away dirt and chalk anywhere on the walls. Rinse very thoroughly. Use a high quality oil-based primer to allow for good adhesion before applying a new latex top coat.

Resin Brown Spots

Softwoods with knots can leach resin out, which in turn can cause your paint to peel or turn brown.

Repair: When working with wood, always use a good primer first. Always apply two coats of paint. Do not use shellac or varnish on knot areas because it is sure to cause early paint failure.

If you need to fix house paint discoloration and aren’t sure where to turn, call us! Schedule a free, in-home estimate today.