Bricks can lend a rich character and sense of history to structure. With occasional washing, they could last for a very long time. However, frequent exposure to various outdoor elements may cause the accumulation of different stubborn stains on brick surfaces. If left unattended, not only will they make bricks appear unattractive, they can also cause premature deterioration. Following below are three of the most common stains or buildup that affect bricks and the cleaning techniques that can be used to eliminate them.
Dirt and Pollutant Crusts
Dirt or soiling on brick surfaces may consist of dust, grit, sand tarry soot or a combination of such pollutants. They may be due to heavy vehicular or human traffic in the area. It should be noted that dirt or soiling can cause brick dissolution and incipient decay. Thus, removal of these things should not be disregarded.
Buildup of dirt and pollutant crusts on brick surfaces can be removed through a combination of low-to-medium-pressure washing and surface brushing or hand-scraping. The method can done using a common garden hose or a pressure washer. When using this technique, it is always best to start with the lowest pressure possible and gradually increase the pressure to loosen dirt and other stubborn pollutants. To further remove heavy grime, gentle hand-brushing or scraping may be employed. In some cases, non-ionic detergent can be added to the water to hasten the process of removing the problem. However, if such cleaning product will be used, the brick surface must be thoroughly rinsed so that no visible or gummy detergent film will be left behind.
Industrial stains on brick surfaces result from contact with oil-based like tar, smoke and soot. If industrial strains are superficial (only affecting the surface of the bricks), they can be easily removed by gently scrubbing the affected area with water-based household detergents that do not contain any acid and alkaline. Organic solvents like mineral spirits are also effective in eliminating these types of stains and water rinse should be done afterward.
For industrial stains that have penetrated the bricks deeply, it is recommended that a poultice should be applied on the affected areas. Simply put, a poultice is made up of an absorbent material or powder that is mixed with liquid to create a paste. When applied on the affected areas, the poultice will help dissolve the stain.
There are different absorbent materials that can be utilized to make poultice. The most common ones used for large scale cleaning projects include clays, chalk, talc, sepiolite and methyl cellulose. For DIY applications, however, absorbent materials like shredded white paper, baking soda or sawdust can be combined with hydrogen peroxide to create the poultice.
Lichens, moss, algae, fungi and other forms of vegetation usually grow on brick surfaces. While these growths may seem harmless, they tend to encourage deterioration because they attract moisture which is one of the worst enemies of bricks and other masonry materials. They also leave behind unsightly black streaks that affect the aesthetic of bricks. Due to this, it is best that they are removed immediately.
Most biological growths, such as algae and lichens, can be removed with water and gentle brushing of stiff natural bristle brush. The stains caused by mildew may be eliminated using organic solvents, but are best treated with bleach or ammonia diluted in water. When using the latter option, though, caution should be taken as the aforesaid cleaning compounds may stain the bricks. At the most, water rinsing should be done after diluted solutions are applied on brick surfaces to keep discoloration at bay.