Selected Answers

From Karl Kardel of Kardel Company on June 12, 2018:
While the chemistry of the brick can impact the ty ...read more While the chemistry of the brick can impact the type of efflorescence, water inside the wall remains the big issue. Planters, coping tops, extensions collect larger amounts of water than surface exposure. Wire-cut brick and open faces collect more water. The designer needs to know these issues. Cures, such as impermeable sealers, will or can destroy the wall. Water-shedding 'sealers' such as silicone can help in sealing hairlines and surface adsorption. Always test. Never use epoxies, urethanes or acrylics, which make a shiny film. Mostly, it is a 'first blush' that, once cleaned, goes away.

From Zenith Czora of Durotech Industries, Inc. on June 7, 2018:
Factors that cause the efflorescence to occur are ...read more Factors that cause the efflorescence to occur are water, rain and snow, which are the primary sources of moisture; salts, including alkali sulphates and carbonates; wall structure that bears passage of water; and weather conditions. Soluble salts are derived naturally from clay bricks and also from cementitious products or mortar. No efflorescence would occur if there is no presence of water. It is the water that dissolves the salt into solution and then carries it onto the surface of the bricks. And when water evaporates, the salts crystallizes and remains either on the surface or within the clay bricks, resulting in efflorescence. Clay bricks are made of clay, which contain highly soluble salts, resulting to efflorescence when in contact with water. To prevent occurrence or recurrence of efflorescence, isolate first the source of water. Any structure should be fixed to prevent intrusion of water into the cavities of the walls. To clean efflorescence off the clay bricks, it is crucial to complete the task of removal in warm, dry weather. If possible, white efflorescence should be allowed to weather out naturally. Use a non-metallic bristle brush to accelerate the removal and then vacuum the loose powders. Any deposits remaining may be removed by wiping with a clean damp sponge with regular rinsing with clean water. Yellow or green efflorescence due to the presence of Vanadium salts can be washed off using inorganic, proprietary, hydrochloric-based brick cleaning solutions.

From Michael Quaranta of OPERATIONS 40 on June 6, 2018:
First, you need to understand how efflorescence is ...read more First, you need to understand how efflorescence is created on and in the clay brick, but also the question should be supported with installation details. Is it a garden application, planter wall or on the 15th floor? You've got to go looking for the creator on the opposite side of the efflorescence and give that source some attention before just trying to remove the unsightly mess.

From Trevor Neale of Blastco on June 5, 2018:
Isolate and remove the source of humidity/moisture ...read more Isolate and remove the source of humidity/moisture that is the root cause of the problem.