Concrete Block Fill Calculator
Find how much grout or concrete fills the cores of a block wall, from the wall's size or the number of blocks, with bags and cost.
Change the values and press Calculate to work out your own figures.
From the wall's size
Enter the wall's length and height and its thickness.
Show the working
- blocks = wall area × 1.125 (8 × 16 in faces)
- grout = blocks × 1.0 cu yd ÷ 100
From the number of blocks
Enter how many blocks to fill.
Show the working
- blocks as entered
- grout = blocks × 1.0 cu yd ÷ 100
How to use it
Enter the wall's length and height and its thickness. Enter how many blocks to fill.
Lengths can be decimals, fractions or tape entries such as 12' 6 1/2" (in feet or inches). Prices are optional.
Key facts
blocks = wall area × 1.125 (8 × 16 in faces) grout = blocks × cubic yards per 100 blocks ÷ 100
Grout
Walls are usually grouted only in cores with rebar (partially grouted); multiply by the share of cores you fill.
Questions
How much concrete fills 100 blocks?
About 1 cubic yard for an 8 in wall.
How much grout for a 40 × 8 ft wall?
3.6 cubic yards for 8 in block.
Formulas
blocks = wall area × 1.125 (8 × 16 in faces) grout = blocks × cubic yards per 100 blocks ÷ 100
Sources
Limitations
- Material densities are typical values (the midpoint of the commonly published range); real loads vary with moisture, grading and compaction, so check with your supplier or type in their density.
- Tank results are the geometric volume; real tanks have wall thickness and fittings.