How do you prevent efflorescence?

Answer 1

Brick Efflorescence Analysis

• Firstly: There must be water-soluble salts present somewhere in the wall.

• Secondly: There must be sufficient moisture in the wall to render the salts into a soluble solution.

• Thirdly: There must be a path for the soluble salts to migrate through to the surface where the moisture can evaporate, thus depositing the salts which then crystallize and cause efflorescence.

All three conditions must exist.

If any one of these conditions is not present, then efflorescence cannot occur. Even though the efflorescence problem is complex, it is not difficult to prevent. Although no economically feasible way exists to totally eliminate any one of these three conditions, it is quite simple to reduce all three and make it nearly impossible for efflorescence to occur.

Brick Efflorescence is the stubborn problem that has caused confusion and trouble for masonry since the first time it appeared thousands of years ago on ancient masonry walls. Efflorescence is normally the white, powdery scum that can appear on masonry walls after construction but can also be brown green or yellow, depending on the type of salts. Nobody likes it, nobody wants it on their walls, but occasionally this persistent problem appears.

Great deals of time, money and effort have been spent trying to solve the difficulties efflorescence generates. Many test programs have been developed and numerous attempts have been made to eliminate this problem. Unfortunately, nothing has proven 100% effective against this very stubborn problem. However, even though no surefire cure has been discovered, a great deal has been learned about how efflorescence works and how to prevent it, and if preventive measures are inadequate.

Consider taking the proactive approach of stabilizing a concrete to prevent moisture from traveling in or out of the matrix. A stabilizing product penetrates into the gel-pore capillary system to form a solid inside. This stops moisture from migrating out to the surface carrying chemicals with it, that then react with the atmosphere.

This migration out to a surface, not only causes efflorescence, it also carries alkali's in the concrete to cause burning or peeling of coatings that have been applied.

Answer 2

I am using a product called Stop Salt. I have been using this product for the last six months, I am amazed! It produces outstanding mortar, the pointing up is brilliant and it cuts out the efflorescence that we all hate as Bricklayers. I hope this can be of some help to you, try it.

If the intent is to "Prevent" efflorescence a penetrating sealer that migrates into a concrete based material, either concrete or cement based mortars should be considered. You should use a sealer that enters the Gel-Pore or Capillary System where it reacts with the alkali to form a solid Inside the matrix. Once this solid is formed, internal chemistry does migrate out to a surface to react with an atmosphere. I use one that does not leave a membrane or film on the surface and has exceptional adhesion bonds with any coatings that may be applied later.

The one I use also has a 15 year waterproofing warranty which prevents contaminates from entering to bring chlorides and low pH conditions to an interior. This creates a No-Low moisture and high pH interior to prevent corrosion cell formation on embedded steel. Choose a sealer carefully and avoid any product that allows for a reapplication at a later date! [What happened to the First coat?] and one that has a 15 year warranty for Waterproofing. This will "Prevent" Efflorescence and a host of other problems you may encounter!