![]() ![]() Lower strength mortars also exhibit better workability, which tends to increase quality of construction. Mortars with lower compressive strengths tend to be easier to clean off the face of the wall than are stronger mortars. ![]() Higher cement content mortars with higher compressive strengths should not be assumed to have better field performance, in fact the opposite is more often true. In general, the lowest-strength mortar that will meet project requirements should be specified. Walls with contrasting mortar and masonry unit colors may require more aggressive cleaning to remove visible mortar. Mortar color should be chosen to match the unit color when smooth or ground faced units are used, as they can be difficult to clean without altering the appearance. 5), contains more information on the various types of concrete masonry unit finishes.Ĭhoosing a mortar color close to that of the concrete masonry unit makes cleaning the wall of mortar smears easier, as the mortar tends to blend in. Typical Sizes and Shapes of Concrete Masonry Units, TEK 2-1B (ref. During construction, mortar and grout smears and droppings should be cleaned off while still easily removable, before they harden completely to the surface. The result is a smooth impervious surface, highly resistant to staining and easily cleaned. Glazed concrete masonry units are manufactured by bonding a permanent colored facing (typically composed of polyester resins, silica sand and various other chemicals) to a concrete masonry unit. This texture is also more suited to cleaning with abrasives, if that technique is required. The rough texture tends to hide minor soiling and makes these units more forgiving of minor efflorescence or other discolorations. Other architectural CMU, such as split faced, split fluted and tumbled units have a natural stone-like texture produced during manufacture. When required, these units can be resealed after final cleaning. When using ground faced units, every effort should be made to keep the units clean and free from mortar smears and droppings during construction. Coatings, which are often used to deepen the color, can also help cleaning efforts by preventing dirt and other contaminants from penetrating the surface. Ground faced units (also called honed or burnished) are polished after manufacture to achieve a smooth finish with the appearance of polished natural stone. In some cases, abrasive cleaning or pressure chemical cleaning are specified with smooth faced units to produce a slightly mottled “stone washed” appearance. For this reason, any aggressive cleaning should be performed consistently across the entire wall surface for a uniform appearance after cleaning. Aggressive cleaning methods may remove this layer, exposing aggregate and altering the final appearance. Concrete Masonry UnitsĬonventional, or nonarchitectural, concrete masonry units (CMUs) have a relatively smooth surface, formed from a thin layer of cement paste resulting from the typical concrete masonry manufacturing process. In addition, special consideration should be given to walls incorporating more than one material, such as a concrete masonry wall with clay masonry banding. Cleaning products and techniques applicable to one masonry wall may not be appropriate for others. The ease of cleaning a masonry wall can be affected by the concrete masonry units and mortar used in the wall. For information on removing stains or localized contaminants, refer to Removal of Stains From Concrete Masonry, TEK 8-2A (ref. This TEK discusses several general cleaning methods, applicable to whole-wall cleaning. Appropriate cleaning can remove contaminants and help produce a more uniform appearance. Subsequent cleaning may be required over the life of the building to address dirt and soot from the atmosphere or staining from specific sources. Cleaning of mortar smears, construction dirt and possibly efflorescence from the construction phase is usually required. ![]() Proper cleaning after construction and throughout the life of the building will help preserve concrete masonry’s beauty.Īlthough the maintenance needs of a well-designed and constructed masonry wall are minimal, contaminants can detract from an otherwise attractive structure. Concrete masonry buildings offer exceptional beauty, coupled with attributes such as structural strength, durability, fire resistance, acoustic performance and low maintenance. ![]()
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |