Why Do Concrete Blocks Have Holes In Them?

Why Do We Provide Holes In Concrete Block?

The openings are called “cells” and one reason they are there is because they make the blocks lighter and easier for a mason to handle. But the primary purpose of the cells is that they align from top to bottom of the wall when laid, and enable a builder to fill some cells with grout/concrete to strengthen the wall. It is often done at sides of larger window and door openings, and vertical steel reinforcing bars are added.

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