Understanding Concrete, Cement, and Mortar

In this video, Ask This Old House host Kevin O’Connor explains the differences between three popular masonry materials.

Steps:

1. Portland cement is a fine gray powder that hardens when mixed with water. It’s seldom used by itself but is an important ingredient in many other masonry products.

2. Concrete is a mixture of portland cement, sand, and an aggregate, such as gravel or coarse stone.

3. Concrete is mixed with water, then poured or pumped to create foundation walls, footings, piers, slab floors, driveways, steps, and sidewalks.

4. Once fully cured, concrete can support immense structural loads.

5. Mortar is a mixture of cement, lime, and sand, and is commonly used to hold together bricks, concrete blocks, and stones.

6. Masons use a wide variety of trowels to apply, spread, pack, and tool mortar.

7. When cured, mortar is somewhat softer than concrete, which allows it to accommodate a small amount of movement in a wall without cracking or crumbling.

8. Concrete, cement, and mortar are available in various strengths and mixtures, so be sure to get the right one for your job.