There is little debate over brick's reputation as a durable, maintenance-free building material. Brick buildings that are hundreds of years old are still in use today. However, many people don't realize that the older brick buildings were not built like today's brick-veneered buildings. Historically, brick was used to create loadbearing walls, which were often four or more wythes of solid brick masonry. These walls prevented moisture penetration to the interior by their sheer mass. The brick masonry in today's veneer wall is just one element of a drainage wall system, which typically consists of a single 4-inch-thick wythe of brickwork, an air space of 1 inch to 2 inches, and a separate wood, steel, or concrete block backup wall. When moisture penetration problems occur, it is usually because the people building the wall didn't understand some of the basic principles of brick veneer construction.
A common misconception, even among some masons, is that 4-inch brick veneer will stop all moisture penetration under all weather conditions. It is important to remember that brick is a porous absorptive material, and that water can penetrate a brick veneer wall wherever there is a lack of material: at bond breaks, hairline cracks between brick...
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