Efflorescence on Walls: Expert Removal and Prevention Tips

Starting to notice a fuzzy white stain on your brick, block, or concrete walls? That’s efflorescence and it can leave some stubborn stains on your walls. 

So what is efflorescence and is there anything you can do to remove or prevent it from appearing on your walls? 

Yes, there is! You’ll learn everything you need to know in this 5-minute read.

What is efflorescence?

Efflorescence is a crystalline deposit that sometimes shows up on masonry surfaces — cement, mortar, concrete, brick, block, and other porous materials. It happens when moisture combines with water-soluble salts in the masonry, reaches the surface, and then evaporates.

When that happens it leaves a white, grey, or green mineral deposit. It’s common to see this happen on basement block walls or exterior brick walls. You’ll even notice that sometimes it almost looks “fuzzy” as if the wall had little white hairs!

How to Remove Efflorescence on Walls

So if you’re starting to see this white discoloration, what can you do about it? Here are some tips for removing it from masonry walls. 

Tip # 1 – Start with a dry brush

The best thing to do is to grab a stiff brush or broom with stiff bristles and brush away! That’ll help remove most of the surface salt deposits and any of that fuzzy stuff you see on the wall. 

NOTE! It’s important to do this before you douse the wall with liquid. If you start right away with water, some of that salt will mix with the water and soak back into the wall. That could cause the efflorescence to resurface again. 

So if you start with a dry brush, you’ll remove the current stains and help prevent them in the future!

Tip #2 – Wet brushing

If dry brushing didn’t remove it all, now it’s time to get out a bucket or a hose and keep scrubbing.

  • – Douse the wall with water
  • – Scrub the stains
  • – Rinse with water
  • – Repeat the process as needed

Tip #3 – Use a DIY cleaner

Some white deposits can be removed with a mild acid solution. It’s best not to use anything too strong since it could actually etch and damage the surface of the wall (not to mention acids like muriatic acid are really dangerous). 

How to Remove Efflorescence on Walls - Use a DIY cleaner - AXMASONRY
  • – Mix one part white cleaning vinegar with two parts water
  • – Spray, brush, or sponge it onto the surface
  • – Scrub it with the brush
  • – Rinse thoroughly with water to remove all of the acid solution
  • – Repeat the process as needed

*Anytime you work with strong chemicals and acids like white vinegar, don’t forget to use rubber gloves and safety glasses!

  • Tip #4 – Use a store-bought cleaner

    If despite following the first 3 tips, you’ve still got that white coating on your masonry wall, it’s time to bring out the big guns — a ready-made efflorescence cleaning solution. 

    The Foundation Armor Concentrated Concrete and Brick Efflorescence Remover and Cleaner from Home Depot is a popular option. Just follow the manufacturer’s directions for how to use whatever product you buy.

    Careful! – While you can use a pressure washer to clean it, if you don’t use the correct detergent and aren’t careful you could actually do more harm. 

What can I do to prevent efflorescence on walls? 

What can I do to prevent efflorescence on walls - AXMASONRY

So are there any ways to stop efflorescence before it happens? You may not always be able to prevent it, but there are two big things you can do to help. Here they are. 

Build Correctly

This is the most important step in efflorescence prevention. If you or your masonry contractor don’t do a proper install, water can seep into places it shouldn’t around your building, potentially causing stains.

Here are some things to keep in mind:

  • – Install vapor barriers where necessary, like under your foundation’s concrete slab
  • – Correctly install flashing around chimneys
  • – Make sure soil is sloped away from your building for proper water runoff
  • – Fill all mortar joints
  • – Add a seal coating to masonry surfaces when necessary
  • – Use high-quality materials that contain less soluble salt 
  • – Use washed sand
  • – Use bricks with special admixtures to reduce efflorescence

Perform Regular Maintenance

Even if a building was built correctly, problems can develop over time that could let water and moisture seep into the wall. So don’t forget to check the masonry parts of your structure from time to time.

  • – Check for structural damage and if you start to notice cracks, fix them quickly so water and moisture don’t seep into the wall.
  • – Get your chimney inspected yearly
  • – Check the exterior mortar joints around the building for signs of deterioration and water penetration

What causes efflorescence on walls?

Don’t forget that efflorescence is caused by excess moisture that mixes with water-soluble salts (calcium carbonate and calcium sulfate) in cement block, brick, and other masonry materials. Then when it reaches the exterior surface and evaporates, it leaves behind stains that are white or grey in color.

While this is a normal occurrence right after a building has been constructed, if it keeps happening years down the road, this would be a sign of a more serious problem. 

One of the biggest things you can do to prevent this from happening long-term is to hire a professional contractor who will do your masonry project right the first time. 

If you’re in the Garland, Dallas, Texas area, give us a call today at A&X Masonry to get your FREE quote!

And don’t miss these other articles with more tips on dealing with efflorescence:

  • List Item #1
  • List Item #2
  • List Item #3
Shopping Basket