MAY 2003

EACO CHEM NEWS

Efflorescence is a complex subject without just one single answer. Cleanup efflorescence, calcite, lime run, weather efflorescence, and white scum are all different types of efflorescence. In this issue, we will discuss cleanup efflorescence and calcite. Stay tuned for solutions for lime run, weather efflorescence, and white scum in our next issue.

REMOVAL PROCEDURES

1.) Cleanup Efflorescence:

Much of the concrete block industry is using integrally waterproofed colored masonry units. These units can be difficult to clean with HCL products, as calcium salt may show up all over the surface, that was until NMD80 arrives. NMD80 applied at a 4:1 dilution will not create this problem and will remove it if some other product caused it. The NMD80 hydrochloric acid component is so thoroughly bound up with the additives, it is not free to bond with the calcium of the colored masonry units. The combination of integral waterproofing and NMD80 will result in stunning color clarity and ease of cleaning. Blocks without the integral waterproofing still seem to have greater problems with color fastness and a hazy appearance, though the clean will be just as easy with NMD80. Occasionally some pockets of residual construction moisture will allow a very light efflorescence to occur after cleaning. EF - fortless is a safe product to spray on and allow to dry on the surface and will retard the redepositing of calcium chloride on the surface for a considerable period of time and possibly solve it forever. When we refer to an end to cleanup efflorescence, we are referring to the use of NMD80 to clean the integrally waterproofed c.m.u.'s, brick and stone.

2.) CALCITE:

This is the most difficult type of efflorescence to deal with easily. It is characterized by a hard and dirty white appearance. Common on brick and block, it starts in the mortar joints and washes down over the face. Calcite and efflorescence are the reasons why EF - fortless was created. EF - fortless has the capability of being used on the surface repeatedly without harm to any masonry or cementitous surfaces. This is a crucial characteristic of any product that is used to remove calcite, as it is often thick and is removed in thin layers, one application at a time. Raw hydrochloric acid is generally not a good solution for the removal of calcite because it is not safe for the surface when using multiple applications. Since the reformulation of GS Restoration (GSR), we have found that in numerous situations, a couple undiluted applications of the GSR opens the pores of the very heavy calcite and some lime runs, allowing fewer applications of the undiluted EF - fortless to totally clean the surface. Removing calcite can be performed with or without a pressure washer. One of the secrets to calcite removal is letting the remover sit while spraying other areas of the wall. Scrubbing the chemical on is not cost effective. Tests should be run when using GSR to determine color fastness of the surface. If it appears to mark, either rinse it quickly, or just use EF - fortless. If the calcite is on concrete walls or exposed aggregate panes, the above techniques may be employed, or try NMD80 at 4:1. - Lynn Peden, President

Two applications of GS Restoration is applied to break the hard surface.

EF - fortless is applied repeatedly without rinsing to finish the job.

Each application shows reduced foaming. No color change or damage occurs.

As long as the water penetration problem is solved, calcite will not return.

Special Solutions:

If the problem occurred using another product, fix it easily and safely with one of these solutions:

SafeRestore: Coating Removal

SafeRestore: Vanadium and Manganese Stains

EF - FORTLESS: Color Safe Efflorescence Removal

NMD80: Removing Cleanup Efflorescence