In this 5-minute read, we’ll look at a few things to consider at different stages of a masonry project in order to prevent and remove efflorescence.
Let’s get started!
Starting to see some white or greyish stains on masonry surfaces around your house? It’s probably efflorescence — crystalline salt deposits on the surface that can sometimes even look kinda “fluffy” or “furry”. It’s caused when moisture penetrates the porous material, mixes with water-soluble salts, and comes to the surface.
If your kids are into science experiments, they’ll probably love looking and touching it 😜. But it can leave unsightly stains around your house and even be a sign of a more serious problem.
So what can you do to prevent efflorescence?
Here are a few things you and your contractor can keep in mind when choosing building materials.
Sand can contain salts that contribute to efflorescence. That’s why it’s important to use sand that hasn’t been contaminated by seawater, soil runoff, or decomposed organic compounds.
The alkali content of portland cement can contribute to efflorescence formation in concrete, grout, brick walls, and mortar. That’s why most modern cement products have a specified allowable alkali amount to help reduce efflorescence and other reactions.
If you or your builder are mixing the concrete or mortar yourselves, double-check any admixture solution to make sure you’re not adding unnecessary salt to the mix. Calcium chloride is often used as a mortar accelerator. When you use too much, it can contribute to efflorescence.
The primary source of moisture that penetrates porous masonry is rainwater. So the best way to prevent efflorescence is through proper building design that prevents rainwater intrusion.
If the below-grade section of walls isn’t properly waterproofed, then water can percolate vertically through the bricks or CMUs (concrete masonry units). This is easy to prevent by applying a waterproof membrane to the below-grade section.
Masonry trim elements often get a direct hit from rainwater. That water and the soluble salts can migrate down into the wall below it and then come out on the surface as efflorescence.
For preventing efflorescence, be sure to:
High-quality workmanship is another important way to prevent efflorescence. That’s why it’s important to hire a masonry contractor with a proven track record.
*If you’re in the Garland, Texas area, give us a call today at Alexander and Xavier Masonry. We’d love to discuss your project and give you a FREE quote.
Masons should completely fill all mortar and grout joints. They should also work to limit any mortar droppings into airspaces since these can work like a bridge to transfer efflorescence to the facade surface. It’s also important to properly install flashing and waterproof sealant where needed around the building.
Any unfinished brick walls should be properly protected with plastic or a tarp. If they’re exposed to rainwater, they can get saturated with water which will promote efflorescence.
You can catch problems early by performing a regular inspection of all the masonry around your building. If you notice any cracks, deteriorating mortar, or sealant that’s old or separating, fix it right away.
Clean heavy efflorescence stains with a brush and water. You can also use a DIY cleaner made from vinegar and water, or a storebought efflorescence cleaner. It’s best to do this in warm weather when the bricks will dry quickly. Let them absorb too much water and you could actually be causing efflorescence in the future.
Waterproofing sealers can help to prevent efflorescence. They minimize water absorption through the wall or floor surface. Less moisture = Less efflorescence.
However, if moisture is getting in through another way, don’t seal the surface. Trapping the salts at the surface of the brickwork or concrete can contribute to faster brick deterioration.
Sealing concrete or masonry can help prevent efflorescence. However, the best way is to follow proper design and construction practices to help prevent it in the first place.
In some cases, yes. Once all the salts in the bricks, pavers, or concrete have dissipated, the efflorescence may stop. However, if water intrusion continues, efflorescence can continue for some time.
You can, but it’s not the best idea. Pressure washing will remove surface deposits. However, it won’t solve the underlying cause of it. And it can easily damage the surface and push moisture and salts farther into the materials, which will lead to efflorescence production in the future.
