EaCo Chem - Brick Restoration
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Brick Restoration

For Professional Use Only

Brick restoration has four main types of cleaning situations, they are:

  • Porous brick
  • Glazed brick
  • Dry pressed brick
  • Wire or water cut (scratch face) brick

While all of the bricks can be successfully cleaned using one of our restoration grade products, the technique used for cleaning may vary. Before going into the individual techniques, I would like to address a common situation. As water migrates through the masonry wall (due to roof leaks, bad capping or deteriorated mortar joints), it creates deposits we call black crust. The chemical make-up of the stain may vary with the substrate and environment; we consistently recommend Stripper Cream. It does not pay to try and hurry this removal process, as inadequate dwell time simply increases the number of times the process is repeated. If the temperature is above 68° F and Stripper Cream’s chemistry mixes optimally with that of the stain, an hour dwell time may be adequate. Scratch tests should always be performed before removing the caustic. If you scratch with a putty knife and do not see the substrate (the surface you are cleaning), leave the caustic on longer, mist the surface with water, or add more product. If you see no reaction at all, we recommend trying NMD 80 undiluted, sprayed on repeatedly, followed by a pressure wash rinse.

 

The chemicals used in our brick restoration process include:

OneRestore® - OneRestore® removes virtually all of the most stubborn stains that can occur on brick including the deepest pollution stains (vanadium, manganese, rust, etc.) without using harsh chemicals. OneRestore® has a mild odor and is safe for use on many surfaces (including glass and anodized aluminum) and around people.

OneRestore® GEL - OneRestore® GEL gives the same quality of clean as its liquid counterpart. The gel allows a longer dwell time without drying, making it more effective under eaves and sills. OneRestore® GEL is not recommended for application to glass or anodized aluminum; the rinse water will not harm either surface when performing a thorough rinse.

GS Restoration - GS Restoration is our ammonium bifluoride product. It has been used for years in some seriously tough situations. GSR was designed to be the safe alternative to heavy duty acids. While it is not recommended for use on glass, many buildings have been cleaned without covering the windows. Extreme caution should be taken to protect surrounding surfaces.

Stripper Cream - Stripper Cream is a thickened multi-layer paint remover. It is very slow to dry and can remain on a surface for days. It is the recommended product to remove thick, external black crust from limestone, as well as graffiti and vine stems.

Porous Brick

Porous brick has traditionally been cleaned using hydrofluoric acid. While cleaning with hydrofluoric acid is generally quick and effective, it is dangerous and requires constant attention to safety, as well as protecting virtually every surface. Beginning in the 1970’s, we at EaCo Chem started work on a much safer alternative, GS Restoration. GS Restoration is our ammonium bifluoride product that channels the power of HF by using elements far more safe for substrates and users. GSR was a superior option for almost every situation.

It wasn’t until the early 2000’s that we came out with OneRestore®, which is a hydrochloric based detergent. The buffering in OneRestore® enables it to be safer for use than traditional methods and even more effective. While straight hydrofluoric acid presented challenges to adjacent substrates, OneRestore® virtually removes those challenges and presents further opportunity. We always recommend proper testing prior to full scale cleaning on brick or any other substrate to assure compatibility.

To start the cleaning process on porous brick, pre-wet the area to be cleaned. Work in sections that you can comfortably cover without allowing the chemical to dry. Always work in a repeatable pattern; the hallmark of quality restoration is evenness and consistence in appearance. Since OneRestore® is a spray on/rinse off product, you will be able to cover a much larger area than bucket and brushing. Generally in brick restoration, we recommend starting at the bottom and working your way to the top. This allows the surface below to stay clean and wet and less likely to stain, although you can start from the top down and achieve excellent result. Spray the OneRestore® undiluted to a wet wall (the wall should not be saturated) and allow it to dwell for approximately five to ten minutes without letting the product dry. If testing shows multiple applications are needed, apply the next application without rinsing.

After all the applications have been applied, thoroughly rinse with a pressure washer. I recommend a four gallon per minute unit at 2,000 PSI. We know bigger pressure washers and are quite common, but we also know you are looking for excellence and craftsmanship. A five gallon per minute at 3,000 PSI machine gives you 15,000 cleaning units of power at the nozzle. A four gallon per minute at 2,000 PSI machine gives you 8,000 cleaning units of power at the nozzle. The truth is that if you are using power to clean, you are water blasting, not cleaning. 36,000 PSI can cut through steel, but it cannot lift out a rust stain from brick! The right chemistry does the cleaning without harming the surface and at an appreciably lower maintenance and labor cost. Using the right chemical and 8,000 cleaning units will be sufficient, cleaning with increased safety for the substrate, precision on the part of the user and equal results 99.5% of the time.

Glazed Brick


Glazed brick is smooth in appearance, due to the finish that uses the same raw materials that are in glass: silica, a flux and water. Fired to a high temperature, the brick has a dense finish that does not absorb water. This finish is even more similar to glass in that it can be burned by chemicals just as readily. In fact, the original purpose of GSR was to clean this type of brick without damaging the surface. Glazed brick is a situation where two mild applications are better than one very strong application. GSR is best used at a higher dilution with a double soak. Certain glazes have a tendency to absorb pollution or metallic stains. The stains tend to be black and occur most often under sills eaves on houses. They generally originate from air borne solids, clay or dirt. GSR is optimized for removing these stains without requiring glass to be covered. When using GSR, keep surrounding surfaces wet, especially those that overspray could potentially land on.

One myth about chemicals is that “right out of the jug” is as strong it will ever get. This is not true. In fact, all liquids being applied as restoration detergents contain water. It doesn’t matter how much water they contain, eventually the water will evaporate. As it evaporates, it leaves the chemical solids reacting on the surface at a higher concentration (stronger than “out of the jug”). This is when burning occurs. The key is not allowing the chemicals to dry.

The other option for restoring glazed brick is OneRestore®, which offers more versatility and safety. Much like on porous brick, OneRestore® is capable of removing some of the toughest stains possible. While GS Restoration was developed for this exact type of brick, over the years we have found that OneRestore® is the best overall product for this or any type of restoration work. There will always be a place for GSR; however, more cautions is necessary when using the product. OneRestore® has a few simple rules of use.

  • Do not allow it to dry on glass or anodized aluminum
  • Do not use on self-cleaning glass or glass with a metallic oxide finish on the outer shell
  • Be sure to test properly to make sure it is compatible with all components of the building

 

The application process will be the same for porous brick. Pre-wetting is not necessary unless it is used to flash cool the surface. Since glazed brick is not porous, the water will run right down the wall.

Dry Pressed Brick

Dry pressed brick is one of two types of brick that have been problematic to clean in the past. Results may vary on this type of brick, depending on what methods were used in the past to restore them. Dry pressed brick has a smooth finish but is very porous, which allows quick absorption. Prior to the development of OneRestore®, the only real way to clean this type of brick was with a heavy acid (hydrofluoric) which was needed to penetrate deep enough to lift out stains. The problem is that hydrofluoric acid will burn the surface and set the stains simultaneously. The techniques suggested used to include a two step process with LCS and GSR. While the results were acceptable, we could never claim excellence.

With the development of OneRestore®, the ability to achieve excellent results has dramatically increased. There is far less of a chance to damage the surface. Care should still be taken not to allow the chemical to dry; testing is still recommended. As with porous brick, pre-wetting the surface will benefit the cleaning process. Saturating the wall is never recommended.

Cut Face Brick

Cut face brick has traditionally been more difficult to clean due to its grooves. When asked to clean the type of brick with vertical scratches across the face, always demonstrate and make sure the customer knows what they will be getting. Since OneRestore® is so versatile, the results will still be better than with other products of the past. Testing is the key to how much chemical is to be used and what technique will give the best results. Since cut face brick is not very porous, there is very little benefit to pre-wetting (with the exception of flash cooling).

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