Brick and Block Quantity Calculator

Who this is for

Count bricks, blocks and mortar wall by wall. Take off the openings, use the maker's units per square metre, then order with your own wastage figure.

DIYers building a garden wall, a planter or a small outbuilding, self-builders, and homeowners checking the quantities on a builder's or merchant's quote for an extension.

What this helps you track

• The net area of each wall once windows, doors and gaps are taken off
• Single and double skins counted from the same measurements
• Bricks or blocks needed from the maker's own figure per square metre
• Units and mortar bags to order with your own wastage allowance
• The cost of each item and of the whole order

How to use it

1. Write the job and the date, then give each wall a row with the brick or block it uses.
2. Measure each wall's length and height in metres, and add up width times height for every window, door and gap in it.
3. Enter the number of skins and the units per square metre from the maker; net area and units are worked out in the browser and the workbook.
4. In the order table, copy the units needed for each product, enter how many come in a pack, or how many one mortar bag lays, and your wastage percentage.
5. Add the prices to see packs, bags and cost; on paper, multiply across each row and round up to whole packs.

Formats

• Printable PDF (A4 and US Letter)
• Fillable PDF with form fields
• Fill in online, saved in your browser
• Excel / Google Sheets workbook

The printable is laid out inside a box that fits both A4 and US Letter, so the two files are identical and neither one is scaled. The fillable PDF has real form fields. The workbook uses plain formulas only — SUM, IF, COUNTIF and the like — so it opens in Excel, LibreOffice and Google Sheets without anything breaking, and every calculated cell is grey so you can see which figures it worked out.

How to print

Download the A4 or US Letter file to match the paper in your printer, open it in a PDF reader and print at 100% — not "fit to page", which shrinks the writing space. Both files leave a 14 mm margin, which clears the unprintable edge on home printers. To print the online version with your entries in it, use the Print this sheet button, which prints only the sheet and none of the page around it. More on printing.

Questions

Where does the units per square metre figure come from?

From the brick or block maker's data sheet or the merchant's product page. It depends on the unit size and the joint, so the sheet supplies none. Enter the figure for one skin; the skins column doubles it for a double-skin wall.

How do I work out mortar?

Mortar bags usually state roughly how many bricks or blocks one bag lays. Put the units to be laid in the needed column and that figure in per pack. Use separate rows for bricks and blocks, because the figure differs between them.

Should I deduct every opening?

Deduct each window, door and gap that will not be built. Lintels, ties, cavity trays and other fittings are not worked out here; add them as their own rows in the order table with the quantities from your plans.

Does this tell me what wall to build?

No. It counts materials for the wall you have already decided on. Thickness, foundations, ties and anything structural should come from your plans, a builder or the rules where you are.