Concrete is made of gravel, sand, water, and Portland cement. Blocks are stacked and bonded with mortar. Precast stone is usually screwed to a concrete or wood base. Either way, steel bars add strength.
The mortar will fail before the concrete, leaving openings for water. Paint and sealant can help delay this. Because concrete is porous, it can encourage damaging vines and moss.
Every spring and fall
75 – 100 years
Step 1: If your concrete wall is painted or sealed, make sure it isn’t chipped or faded. A seal should look smooth and shiny, and water should bead. If the concrete is bare, look into the benefits of painting or sealing.
Step 2: Check for cracks. Small, vertical ones are common and may arise due to temperature changes or settling. Horizontal cracks, cracks larger than 1/8 inch, and “step pattern” cracks can be more serious. If you find any, have a professional take a look.
Step 3: Look for loose or crumbling mortar. Repair mortar ASAP to keep water out of your home.
Step 4: Remove anything growing on the walls. Moss, lichen, mold, and vines can damage masonry. Make sure shrubs are trimmed back at least 6 inches from your walls.
Step 5: Stained concrete or areas that stay damp may indicate a moisture problem. If you have precast stone, make sure there aren’t any gaps at corners, seams, windows, or doors. If you’re concerned, contact an environmental testing professional to conduct a moisture test.