What Kind of Weathering Affects Brick Walls?

Hail

• Hail is hard on most types of building covering, but it takes a very serious hailstorm to damage brick. Although bricks are strong, once hailstones get large enough, even brick is not strong enough to stand up to pounding from the high-velocity balls of ice. A heavy hailstorm rated on the hail severity scale from 1 to 10 as an H6 may chip, dent and damage brick all over the exterior of a home. The larger the hailstones, the more likely that the brick won't be able to stand up to the pounding.

Frost

• In regions where the temperature fluctuates frequently from above to below the freezing point, exterior bricks are subjected constantly to frost. This is especially dangerous when high levels of moisture or precipitation soak into the brick. When frost attacks wet bricks, the mortar holding the bricks in place starts to fall apart. Over time, this jeopardizes the stability of any bricks the mortar holds in place. The bricks themselves may also start to break after enough frost damage.

Extreme Cold

• Brick is very resistant against most forms of extreme weather. However, if it gets cold enough, especially if that cold is attacking bricks that have absorbed moisture, the bricks are vulnerable to damage. In the northern reaches of the country, like parts of Minnesota, it can get to minus 40 degrees F and lower in the winter time. Brick could certainly sustain damage under that kind of temperature stress.

Rain Storms

• In a windstorm with heavy rain, such as what occurs during a hurricane, water may penetrate the brick on the exterior of a house. Water is especially likely to be driven into the mortar of a brick wall when combined with high winds. Older brick construction tends to have very thick walls and will likely be damaged less by this type of a storm. Modern brick houses that only have an outer layer of decorative brick need flashing installed behind the brick to deal with penetrating moisture.