I had never heard of applying a waterproofing compound to exterior brick to prevent cracking from moisture intrusion during freezing conditions, but a contractor proposed and applied it to a neighbor's house. All exterior brick is located above the foundation curb, above grade. Is this a recommended practice? What is the maximum recommended pressure for pressure washing to avoid damaging bricks/mortar? According to Home Depot's Buying Guide for Waterproofers, "Waterproofers stop the flow of water through concrete while sealers only repel water. However, sealers do repel water and allow water vapor to move through the material. Apply these products to brick, concrete, block, stucco or other masonry material."