Spring cleaning may be over and done with, but you can clean statues all year round. Add the service of cleaning statuaries to your resume and offer clients a way to keep their garden and landscape pieces looking in top shape.
When it comes to garden statuary, the question of what is dirty is very subjective. In some cases the dirt can increase the beauty of a piece and create a more realistic appearance, while in other cases the piece may look worn out due to dirt. Once the decision has been made to clean the piece or let it be, there are different options depending on the base material. It is best to identify the base material before charging forward with a cleaning method. Some materials can look very similar when weathered. If there are visible signs of severe deterioration, it is best to leave the piece alone, as the dirt may be the only thing holding it together! If it must be cleaned, use the least invasive procedure.
A thorough high-pressure washing may be all that is necessary to bring vibrancy to any aging piece. This procedure has the advantage of not affecting surrounding plant life and it can clean out deep crevasses. Use a slow sweeping motion at close range to remove the built up dirt. Unfortunately, not all statuary is in an area with access to water and electricity (necessary to operate most power washers), making this option out of the question. If the piece is painted and the paint is to remain, it is best to stay away from areas that are beginning to peel, and, in general, you may need to implement a lower pressure option to not damage the finish.
One of the most common forms of statuary is cast stone, or concrete. There are different mixtures of cast stone, some with a high natural stone content and others with only sand. For the most part you can treat them all the same if they are in good condition.
Some concrete statuary may be painted and, like any coating, paint will eventually begin to peel or flake off. If your client wants the paint removed you can use an actual paint remover. Read the label on the removal product to determine if it is suitable for concrete. If your have commercial clients, you may sometimes need to remove graffiti. You may also use paint remover for this task. There are specific products on the market that tout their ability to remove graffiti; research these carefully before investing in them. If you use a paint remover in only one area of the statue, it may result in discrepancies in the color and texture. You can feather these away from the area to make it less apparent or you can use a milder chemical to wash over the entire piece. This must be done after all traces of the paint remover are gone to avoid a negative chemical reaction. Wash over the entire piece with a mixture of one part muriatic acid to five parts water.
You can also use some standard household cleaners like Simple Green with great success to brighten an aging finish. Apply these with a scrub brush and work in the solution. Vigorous scrubbing may be necessary to really get the piece clean.
The most aggressive cleaning method of soiled cast stone statuary would include the use of muriatic acid. This method is not recommended for very old concrete or concrete where 80 percent of the surface area already shows the aggregate which was used. Acid will remove grease, oils, rubber scuff marks and other non-paint contaminates. It will also remove the very top layer of cement slurry on a concrete statue, which in most cases, will add to the beauty of a piece by making it look aged. Take precautions when using muriatic acid due to the strength of the chemical. Use rubber gloves, safety glasses and a respirator to protect yourself from the acid. For a basic cleaning, use a mixture of one part muriatic acid to five parts water. If there are particularly stubborn areas, the mixture can be made stronger by adding less water. Brush the acid onto the statue and, in the extremely soiled areas, use a bristle scrub brush to work in the acid. Allow the acid to sit on the piece for no more than 10 minutes and then remove the acid with water. Continue until the piece is clean and uniform in texture.
GLASS FIBER REINFORCED CONCRETE
Glass fiber reinforced concrete (GFRC) is gaining popularity as statuary material and can be treated similarly to the concrete statuary. However, do not use paint removers and muriatic acid on these surfaces. The first attempt to clean GFRC should always include a household-type cleaner, such as Simple Green. Some suppliers of GFRC statuary offer an option of adding an anti-graffiti coating that allows you to clean the statuary using MEK (methyl ethyl ketone). MEK dissolves the spray paint, which you can then remove with a high-pressure wash. Repeated use of MEK will diminish the qualities of the anti-graffiti coating and a new coating will be required. If a finish was placed on the GFRC, the supplier may have a repair kit available.
Bronze statuary is the most resilient material available, which makes it a prime choice for public places. In most cases, all that is necessary to clean a bronze statue is a thorough high-pressure washing. In the absence of this, scrubbing with a neutral pH household cleaner will do the job. You should not use chemicals stronger than household cleansers. It is the nature of bronze to have streaks of different colors as a piece increases in age and this is a desirable quality. This can only be counteracted with a full sandblasting, followed by the application of a new patina, neither of which can be easily done on location or by anyone other than a bronze craftsman.
Natural stone statuary is difficult to clean and, for the most part should be handled only by a qualified stone carver with knowledge of restoration. For instance, you must treat marble statuary differently than limestone due to their different textures and porosities. In addition, the patina that is taken on by natural stone is most usually desired and adds to the value of the piece. With natural stone statuary that has little to no details or undercuts, you can use a high-pressure wash. This process is not recommended for detailed pieces, as the possibility of popping off a delicate section is too great. Natural stone tends to have fissures that hold water and, therefore, are more susceptible to cracking and chipping than cast stone. A restoration professional supplied this secret formula for brightening white marble: Apply a paste-like mixture of powdered cleaner and bleach to a statue moistened with water, then wrap the statue with plastic wrap and allow it to sit for 24 hours. Unwrap and rinse off, scrubbing soiled areas if necessary. This method can be used on other materials like cast stone, but you should test a small inconspicuous area.
Lead is the least common form of garden statuary and will most likely not be found in a public garden. If you do need to clean a lead statue, you can use Simple Green or another household cleanser along with a soft bristled scrub brush. Never use a wire brush or scouring pad as this will cause harmful lead dust and will affect the finish of the piece. Lead will have streaking of white and grey and it should not be painted or treated with any chemicals.
MAKE IT LAST
Again, remember to always determine what material you are cleaning before proceeding with a method. Start with the least invasive cleaning and work your way up from there. Use caution rather than brawn with natural stone and lead. Most importantly, make sure that your client wants the statuary to look new again before taking away the aged patina.
Maria Lynch Dumoulin is vice president of manufacturing for Kenneth Lynch & Sons (Wilton, Conn.).
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