Concrete
Concrete block calculator
A block wall takes 1.125 blocks per square foot of face, whatever the block's width: a 50 × 6 ft wall in 8 in block is 355 blocks with 5% waste — 4 pallets, 6.7 tons. Reinforced, on a footing and capped, it costs about $5,996 built, or $2,556 in materials if you lay it yourself. The mortar, the core fill, the rebar and the footing are all counted below.
Written and edited by Pablo Ruiz Quintero
Last reviewed 2026-09-30 · Nothing you type leaves your browser
Concrete block and cinder block calculator
The wall, the block and the steel
A standard block with its mortar joint covers 8 × 16 in, so 1.125 blocks make a square foot of wall whatever the width. The width sets the weight, the price and how much concrete the cores take.
9 courses.
Doors, windows, gates.
The standard block: foundations, stem walls, garage and privacy walls.
A #4 bar in a grouted cell about every 48 in and at the ends and corners, and a bond beam on top — the usual structural wall.
Poured with the wall.
Solid caps on top.
A mason.
Used only to pick a regional labour rate. It stays in your browser.
300 sq ft of 8 in block wall
355 blocks
4 pallets · 6.7 tons · 5% waste included
$5,996 built
$19.99 a square foot of wall · $4,487–$8,092
What the cores take
0.76 cu yd of core fill
The reinforced cells and the bond beam filled with concrete around #4 bars. Under a yard it is bagged; over a yard it comes on a truck.
Hollow, reinforced or fully grouted
50 × 6 ft in 8 in block.
Materials list
- 8 in hollow blocks
300 sq ft of face at 1.125 a square foot, plus 5% for cuts and breakage — 4 pallets of 90.355 blocks · $976 - Masonry cement, 70 lb
3 bags per 100 blocks, mixed on site.11 bags · $165 - Mason sand
1 ton per 100 blocks.4 tons · $136 - Core fill, 80 lb concrete
The reinforced cells and the bond beam on top.35 bags · $217 - #4 rebar, 20 ft
14 vertical bars at 48 in and the ends, two bars in the bond beam, laps included.11 sticks · $132 - Ladder joint reinforcement, 10 ft
In the mortar bed every other course.20 pieces · $90 - Solid cap block
Along the top of the wall.38 caps · $300 - Footing, 16 × 8 in
A continuous footing twice the block's width, with two #4 bars.1.75 cu yd · $540 - Mason
Laying 355 blocks and forming and pouring the footing.$3,440
What it costs
National average. A 50 × 6 ft wall in 8 in block, reinforced cells every 48 in, on a new footing, capped. Not included: excavation beyond the footing trench, stucco or paint, a permit.
The concrete for the footing and cores is priced as on the concrete calculator; a wall holding back soil, on the retaining wall page; a finish over it, stucco.
Worth knowing
- 355 blocks at 38 lb is 6.7 tons — 4 pallets, delivered by a truck with a boom or a forklift, not a pickup.
- The footing here is 8 in deep; its bottom goes below your frost line, so in a cold climate it sits in a trench dug deeper and the concrete count grows.
- Holding back soil is a different job: a retaining wall needs drainage behind it and, over about 4 ft, an engineer. See the retaining wall page for that.
On this page — 4 sections
Counting the blocks
The short version
- 1.125 blocks a square foot, plus 5%.
- 50 × 6 ft: 355 blocks, 4 pallets, 6.7 tons.
- Built: $5,996 — about $20 a square foot.
- 8 in block: $2.75.
A standard concrete block is 7-5/8 × 7-5/8 × 15-5/8 in. With its 3/8 in mortar joint it occupies 8 × 16 in of wall face, so every block width — 4, 6, 8, 10 or 12 in — takes the same 1.125 blocks per square foot. The width changes the weight, the price, and the concrete the cells hold.
blocks = (length × height − openings) × 1.125 × 1.05
| Price | Weight · pallet | |
|---|---|---|
| 4 in (4 × 8 × 16) | $1.90 | 26 lb · 144 |
| 6 in (6 × 8 × 16) | $2.30 | 30 lb · 105 |
| 8 in (8 × 8 × 16) — standard | $2.75 | 38 lb · 90 |
| 10 in (10 × 8 × 16) | $3.40 | 45 lb · 72 |
| 12 in (12 × 8 × 16) | $3.90 | 50 lb · 60 |
National Concrete Masonry Association, NCMA TEK notes — concrete masonry unit sizes, grout quantities and reinforcement · checked 2026-09-30
MaterialsEstimator, Concrete block wall price and takeoff survey · checked 2026-09-30
The whole materials list
| Quantity | Cost | |
|---|---|---|
| 8 in hollow blocks | 355 blocks | $976 |
| Masonry cement, 70 lb | 11 bags | $165 |
| Mason sand | 4 tons | $136 |
| Core fill, 80 lb concrete | 35 bags | $217 |
| #4 rebar, 20 ft | 11 sticks | $132 |
| Ladder joint reinforcement, 10 ft | 20 pieces | $90 |
| Solid cap block | 38 caps | $300 |
| Footing, 16 × 8 in | 1.75 cu yd | $540 |
That is a 50 × 6 ft wall in 8 in block, with a #4 bar in a grouted cell every 48 in and at the ends, a bond beam on top, ladder wire every other course and a continuous footing twice the block’s width. Under a yard of concrete it is bagged; over a yard, a ready-mix truck with the short-load fee.
$2,556
Materials
Hired or not
$3,440
Mason
$8 a block
0.76 yd
Core fill
Reinforced cells
1.65 yd
Footing
16 × 8 in
MaterialsEstimator, Delivered ready-mix price survey · checked 2026-09-15
Hollow, reinforced or solid
| 50 × 6 ft, built | Core fill | |
|---|---|---|
| Hollow, unreinforced | $5,557 | None |
| Reinforced cells every 48 in | $5,996 | 0.76 cu yd |
| Fully grouted | $6,459 | 3.02 cu yd |
A hollow wall is held together only by its mortar — fine for a low garden wall. Anything that carries a load, stands over about 4 ft or holds back soil gets rebar in grouted cells. Filling the cells costs less than people expect, because the blocks and the mason’s time are most of the price either way.
International Code Council, International Residential Code, Section R403.1.4, Footing depth and frost protection · checked 2026-09-16
What goes wrong
Before ordering
- The wall's length, height and openings.
- Block width for the job — 8 in for most structural walls.
- The footing depth for your frost line.
- Where the pallets can be set down.
- A permit, for anything structural or over the town's height limit.
01No footing
The wall settles and cracks at the mortar joints.
Instead — A continuous footing below the frost line.
02Tall and hollow
An unreinforced wall over about 4 ft can topple.
Instead — Rebar in grouted cells.
03A crooked first course
Every course above repeats it.
Instead — Level the first course in a full bed of mortar.
04Ordering to the exact count
Blocks break and cuts waste.
Instead — 5% extra.
- 01Find the wall faceLength × height, less doors, windows and gates.
- 02Multiply by 1.1251.125 blocks make a square foot of wall, whatever the block's width.
- 03Add waste5% for cuts and broken blocks.
- 04Count the mortarAbout 28 blocks per 80 lb bag of type S; or masonry cement and sand for a big wall.
- 05Count the core fill and steelConcrete for the reinforced cells, #4 bars and ladder wire.
- 06Add the footingA continuous footing twice the block's width, below the frost line.
Retaining walls in block, concrete, timber and stone, with the drainage behind them.
If it holds back soil- CMU
- Concrete masonry unit — the standard hollow concrete block, 7-5/8 × 7-5/8 × 15-5/8 in for the 8 in size.
- Cinder block
- The common name for a concrete block. True cinder blocks, made with coal ash, are rarely sold now.
- Nominal size
- The block plus its 3/8 in mortar joint: 8 × 8 × 16 in. Walls are laid out on that module.
- Course
- One row of blocks: 8 in of height.
- Core fill (grout)
- Concrete poured into the hollow cells, around rebar, to make the wall solid and tie it together.
- Bond beam
- A course of channel blocks at the top, filled with concrete around horizontal bars.
- Ladder reinforcement
- Welded wire laid in the mortar bed every other course to control cracking.
- Type S mortar
- The mortar mix used for block walls below and above grade — stronger than type N.
Common questions
- How many concrete blocks do I need?
- Multiply the wall's face by 1.125 and add 5%: a 50 × 6 ft wall is 300 sq ft, which is 355 blocks. A 10 × 8 ft wall is 95. The count is the same for 6, 8, 10 or 12 in block, because they all have an 8 × 16 in face.
- How many blocks are in a square foot?
- 1.125. A standard block laid with its 3/8 in joint covers 8 × 16 in — 128 sq in, or 0.889 sq ft — so it takes 1.125 of them to cover a square foot, or 112.5 for 100 sq ft.
- How much does a concrete block cost?
- About $2.75 for a standard 8 × 8 × 16 in block ($2.00–$3.50). A 4 in block is about $1.90, a 6 in $2.30, a 10 in $3.40 and a 12 in $3.90.
- How much does a concrete block wall cost?
- About $20 a square foot built, reinforced, on a footing and capped: $5,996 for a 50 × 6 ft wall in 8 in block. Unreinforced it is $5,557; fully grouted, $6,459. A 100 ft wall of the same height is $11,710.
- How much does it cost to build a block wall yourself?
- About $2,556 in materials for the same 50 × 6 ft wall — the mason is $3,440 of the hired price — and about 44 hours at 8 blocks an hour.
- How much mortar do I need for concrete blocks?
- About one 80 lb bag of premixed type S mortar per 28 standard blocks. For a bigger wall it is cheaper to mix: 3 bags of masonry cement and 1 ton of sand per 100 blocks — 11 bags and 4 tons for the 50 × 6 ft wall.
- How much concrete fills a block wall?
- About 0.23 cu ft per 8 in block when every cell is filled — 3.02 cu yd for the 50 × 6 ft wall fully grouted, and 0.76 cu yd with reinforced cells every 48 in.
- How many blocks are on a pallet, and what do they weigh?
- About 90 8 in blocks to a pallet at 38 lb each — 3,420 lb. The 50 × 6 ft wall is 4 pallets and 6.7 tons: a boom truck or a forklift delivery, not a pickup.
- How much does a 20 ft garden wall cost?
- A 20 × 4 ft garden wall in 6 in block, hollow, on a small footing and capped, is about $1,553 built — 95 blocks.
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About the author
Pablo Ruiz Quintero — Editor
Editor of MaterialsEstimator. Decides which documents count as a source, what every default value is, and where the line sits between what the reader parses and what the engines compute.
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