Concrete Masonry Units Vs. Precast Walls

White precast concrete wall

Precast walls are made by pouring concrete into forms of specified dimensions to make a whole wall in one piece.

Concrete Masonry Units (CMU or precast concrete block wall) are typically 8” X 8” X 16” blocks that can be stacked to form walls. Both are made from concrete, but depending on your project, schedule, and budget, precast walls may be the best option.

Here is how precast concrete stacks up to CMU:

How are Precast Walls Similar to CMUs?

They are both made from the same materials: Portland cement, gravel aggregate, and sand.

Both options will have the same compressive strength and can handle tight squeezes. For better tension, reinforcement can be added to either type of wall to increase tensile strength.

Steel reinforcement is typically embedded in precast walls during the concrete pouring. Concrete blocks are reinforced by embedding steel rebar into the hollow center using grout or cement after the blocks have been placed.

How Precast Walls Differ from CMUs?

While there are several differences between precast walls and CMUs, including design options, overall quality and more – here are the key basic differences.

Hollow Vs. Solid

This is the main difference between the two options.

Concrete blocks are typically hollow to decrease the weight – making them easier to stack. This can also make them laterally weaker than a precast wall.

Precast walls are solid walls. The precast wall has more mass to resist the lateral load. Reinforcement can easily be added to concrete blocks to increase lateral strength. Without it, the lateral strength of a concrete block wall fence is solely dependent on the strength of the mortar holding the bricks together. Concrete blocks can be filled with grout to make them solid and improve their strength.

Gravel Size

While they are both made from the same materials, the dimensions of these materials are different. The gravel in a precast concrete block wall is going to be larger – up to an inch in diameter. The gravel in concrete blocks will be much smaller – around a quarter of an inch. The smaller diameter helps to properly fill the concrete block mold.

Time to Install

Precast walls are typically faster to install than block walls. Blocks must be stacked like bricks and must either be secured with mortar or covered with a surface bonding cement. Precast concrete wall fences are installed as a single piece using a crane.

Blocks must have a solid concrete slab to build on, while precast walls only need a compacted gravel base. All these factors can make precast walls much faster to install.

Precast Walls and Fences

We’ve been helping engineers, architects, developers, and contractors with a variety of precast concrete projects. To learn more about the benefits of precast walls, contact American Precast, Inc. at 855-235-0881 or get a quote for your upcoming project.