Concrete and mortar are both used in building projects but there are some differences in their composition and therefore their strength which means they should not be interchanged and one should not be used as a substitute for the other. Basically concrete is stronger and more durable so it can be used for structural projects such as setting posts whereas mortar is used as a bonding agent for bricks, stones, etc.
Concrete is a mixture of water, cement, sand just like mortar. However concrete also has gravel and other coarse aggregates that makes it stronger and more durable. Concrete has a low water-to-cement ratio and is a thinner consistency than mortar. Concrete is often reinforced with steel when used a structural support of a building. However concrete can also be supported by the ground such as steps, sidewalks, concrete, appliance pads. It is ideal for setting posts such as fence posts, mailbox posts, basketball posts, deck posts, lamp posts, and swing sets.
One of the concretes we sell is the Quikrete Fast Setting Concrete Mix. It is a special blend of fast-setting cements, sand, and gravel designed to set hard is approximately 20 to 40 minutes. It allows you to set posts without mixing- just pour dry mix into hole and soak. The strength of this particular concrete is 4000 PSI (pounds per square inch) at 28 days.
Mortar, which is a mixture of water, cement, and sand, has a higher water-to cement ratio than concrete. It has a thicker consistency which makes it a great adhesive and bonding agent for bricks and tiles. Mortar mix can be used for construction and repair of brick, block, and stone for barbecues, pillars, walls, tuck-pointing mortar joints, and planters.
We sell Quikrete Mortar Mix which is a blend of masonry cement and graded sand. You simply add water. The strength of this particular mortar is 750 PSI (pounds per square inch) at 28 days.