There is no single standard block size
Products differ by manufacturer, system, finish and region. The presets in this calculator are generic examples, not a branded catalog. Choose the actual installed module from the technical data for your product.
Length and height control the face count. Depth affects the entered base trench width. Hollow cores, tapered sides, setback lips and special corner pieces can change other quantities without changing the nominal face area.
Illustrative unit dimensions
The following examples show how coverage changes with module size. They do not claim that any named manufacturer supplies these exact dimensions. Face area is length × height ÷ 144 when dimensions are in inches.
| Example module (L × H × D) | Face coverage | Where to verify |
|---|---|---|
| 12 × 4 × 8 in | 0.333 ft² | Selected product data sheet |
| 16 × 6 × 10 in | 0.667 ft² | Selected product data sheet |
| 18 × 8 × 12 in | 1.000 ft² | Selected product data sheet |
| 400 × 200 × 300 mm | 0.080 m² | Selected product data sheet |
Pallet counts are packaging information
The default 75 units per pallet is an editable example. Pallets may contain different counts for different sizes, colors, finishes and regional suppliers. A full-pallet purchase can exceed the calculator’s individual-unit takeoff.
Confirm units per pallet, whether partial pallets are available, pallet deposits, unloading equipment and returns. A product with a slightly lower unit price may have a higher delivered project price when its minimum order is larger.
Do not infer weight from exterior size
Solid and hollow units with the same face size can have different weights. Concrete composition and moisture also affect mass. Use the supplier’s stated unit weight and pallet gross weight for handling and transport planning.
This site does not publish invented manufacturer weights. The wall-unit quantity gives you a count to multiply by a verified unit weight, and the gravel quantity uses a separate editable bulk density.
Match the cap and the wall system
Caps may be longer, deeper or tapered differently from the wall units. Overhang and curve layout affect coverage. Use the cap tool with the installed coverage rather than assuming one cap per face unit.
For a masonry unit, distinguish actual dimensions from the nominal module including mortar. For a timber, distinguish nominal section size from actual course height. These are different counting conventions and are handled by the dedicated tools.
References and scope
Arithmetic and worked examples are explained on our methodology page. These manufacturer references provide product-specific context, not approval of a generic wall. Accessed October 1, 2026.
- Allan Block: residential basic installation
- Allan Block: reinforcement installation
- Allan Block: residential retaining wall manual
Read the estimating and engineering limits, or send a correction.