Severe Weather (SW) Brick

Brick is graded by how much water it absorbs and how well it holds up to repeated freezing while wet. SW is the top of that scale, above moderate weathering and no weathering grades, and it's meant for brick that sits at or below grade, caps a wall, or otherwise takes the brunt of rain and snow directly. Using a lower grade in an exposed spot isn't usually visible at first, the difference shows up over several winters as the brick starts to spall.

Our winters put every exposed brick surface through repeated freeze-thaw cycling for months at a time, so grade matters more here than in a milder climate. When we're building new brickwork, coping, or any course that sits exposed to weather or snow load, we spec SW-rated brick rather than a lower grade, because the extra durability is what keeps a wall from spalling apart in five or ten years instead of holding up for decades. It costs more up front and saves a rebuild later.