Lay a strong foundation for a concrete block wall with these simple steps.
prior to beginning, become familiar with block terminology.
The concrete that forms the block is called the web.
The cavities within the block are called cores.
A stretcher block is the common block with ears, or flanges, on the ends.
Stretcher blocks make up the middle of a wall between end blocks and corner blocks.
Leads are the built-up corners of a wall and are three or four courses high.
You’ll build leads first, then fill in between them.
Preparation Tips
Block walls require careful planning, just like any other masonry structure.
It’s easy and strong.
Even if reinforcement is not required, embed 32-inch lengths of rebar vertically in the footing at 32-inch intervals.
The rebar extends into the cores when you set the blocks.
Or you might set stakes with mason’s line to align the outside faces.
Concrete block webs are wider on one side.
The wide side should face up because it provides a larger bed for the mortar.
This reduces waste, minimizing the amount of mortar that falls off the web.
It’s also easier to handle the blocks when you grip the wide side.
To save time, distribute the blocks along the job site with all the wide sides up.
Do not wet the blocks before installing them.
Wet blocks expand, then shrink when dry.
If it rains or rain threatens, cover the blocks.
An exception is when laying reinforcements.
Building codes might also call forconcrete reinforcement.
How to Make a Story Pole
A story pole helps you space the courses more quickly.
To make one, cut a piece of straight 2x4 to the height of the finished wall.
Then mark the courses on the board, separating them by 3/8 inch for mortar joints.
Mark the edges of the block on the footing and snap chalk lines on the surface of the footing.
ensure your chalk lines extend to the ends of the footing.
Place the edges on the chalked lines, spacing them with 3/8-inch-wide plywood.
When you set the last block, snap perpendicular chalk lines to mark the ends of the row.
Then start the second leg of the trial run with a full corner block.
Check the corner with a framing square.
Lay out the rest of the blocks along the chalk lines.
Drop a plumb bob from the intersection of the lines and mark the footing clearly.
Then snap a chalk line between your marks.
