How to Remove Efflorescence and Calcium Stains
What is Efflorescence?
Efflorescence is the result of excessive moisture in a brick wall. Sometimes new construction will develop efflorescence through the natural dry process, which in the business is referred to as “new building bloom.” When the building dries, the moisture in the bricks bring the soluble salts to the surface, leaving white deposits. After the building dries, the efflorescence often will weather off on its own.
However, if a building has a recurring efflorescence problem, moisture is getting in from somewhere. This might be from cracks in the bricks or mortar joints, missing or deteriorated caulking, poorly working gutter or downspouts (think gutter cleaning opportunity!), or something else. But that’s what’s causing the efflorescence and will have to be corrected to prevent it from coming back.
How to Recognize Efflorescence
Efflorescence is white, but so are some other things, like calcium deposits,
There are a couple of ways to test if it’s actually efflorescence.
1. Wet the surface with water and see if the efflorescence “disappears” then reappears as the surface dries.
2. Taste it! Lick your fingertip, rub it on the wall, then taste your finger. If it’s salty, it’s efflorescence. (This is probably not the best option in a post-Covid world, but it does work.)
What are Calcium Stains?
Calcium stains are also white, but they can have a thicker, crustier appearance. Like efflorescence, calcium stains result from excess water passing through the mortar joints. When the water evaporates, it can leave white calcium deposits behind. Calcium stains come in different levels – from powdery to mild or moderate deposits, to sever. Surface calcium stains can be removed. However, more severe conditions run deep into the substrate and require extensive restoration efforts to remove.
How to Remove Efflorescence and Calcium Stains
For removing efflorescence and calcium stains, our go-to recommendation is Front 9 (F9) Efflorescence and Calcium Remover (F9 Efflo), which is a breakthrough in the restoration and cleaning industry. F9 Calcium and Efflorescence Remover is a user friendly, full 31.45% strength muriatic acid replacement. This product combines a buffered, pleasant smelling acid along with an excellent soaping capability to work better at lower concentrations. F9 Calcium and Efflorescence Remover gives the user the advantage of a full-strength product while greatly reducing fuming and corrosion, making it a safer, healthier option than HCL and Muriatic Acid.
Suitable Substrates: F9 Efflorescence and Calcium Remover can be used on a variety of surfaces, including concrete, bricks, pavers, limestone, sandstone, riverstone, exposed aggregate, stucco, shingles, EIFS, glass, synthetic stone, anodized aluminum, unpolished marble and other surfaces.
Unsuitable Substrates: May not be suitable for polished or glazed surfaces. Not for use on metallic or other synthetic coatings or films. Do not use on acrylic and polycarbonate sheet glazing. Always perform a test to ensure compatibility.
How to Apply F9 Efflo for Efflorescence and Calcium Stains
IMPORTANT: Always add acid to water, NOT water to acid!
With F9 Efflo, it’s better to apply several mild applications as opposed to one overpowering dose. To minimize damage, you can also pre-wet the areas around the area you’ll be spraying with water, followed by a 4:1 mixture of water and F9 Double Eagle.
Always test first to confirm compatibility and desired strength. THIS CAN ETCH MASONRY. ALWAYS TEST FIRST!
Pre-Clean if needed to remove oil and debris. Cleaning the concrete first loosens dirt and debris, which makes cleaning easier.
For concrete, brick, pavers, grout and masonry, use the following WATER TO PRODUCT dilution ratio:
· Thick Calcium Stains and Concrete Prep for Coatings: 1:1 up to 4:1
· Medium Calcium Stains: 4:1 up to 8:1
· Light Calcium Stains: 8:1 to 12:1
· Powdery Efflorescence Cleaning 12:1
· General Cleaning 8:1
Cleaning Instructions for F9 Effloresence and Calcium Remover:
1. Always pour cold water into the bucket first, then add product.
Add 1-part F9 Calcium and Efflorescence Remover using the proper ratio of water instructions above. Again, always add acid to water.
2. Mist the surface with water so that it is damp, but not puddling.
3. Using a sprayer, such as the ProTool Power Sprayer -- the most versatile and easy-to-use sprayer on the market -- spray the mixture on the surface to be cleaned. The mixture should begin to foam.
4. Let the mixture dwell for 20 seconds to 3 minutes, but don’t let it dry.
5. Scrub the surface as needed with a hard-bristled brush or broom.
6. Let the mixture dwell for an additional 1 to 15 minutes.
7. Neutralize the surface using F9 Double Eagle.
8. Rinse using a fan tip or surface cleaner. Again, don’t let the product dry.
9. Repeat if needed, adjusting the dilution ratio as needed.