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Masonry

What it's for

Counts the units for a block, brick or stone wall job: one wall or several, less the doors and windows. You get the unit count, mortar bags and sand, grout bags and vertical rebar for block if you ask for them, a coursed elevation of the first wall, and a material list. It is a takeoff. It does not check the wall against code.

Step by step

The example is the screen as it opens: one CMU block wall, 20' 0" long and 8' 0" high, no openings, 10% waste.

Masonry inputs at their defaults: MASONRY TYPE CMU Block (Brick and Stone beside it), WALLS with WALL 1 20' 0" × 8' 0" and its trash button, ADD WALL, DOORS 0, WINDOWS 0, INCLUDE GROUT off, INCLUDE VERTICAL REBAR off and WASTE FACTOR 10%. The answer bar reads 198 CMU Block, an amber Seismic Design Category not asked — A to C assumed; in D0, D1 or D2 (or a townhouse in C) IRC R606.12 governs the reinforcement, and 6 mortar bags · 18 cu ft sand. 1 2 3 4 5
Steps 1 to 5. The grout and rebar rows show for CMU Block only. The amber line under the headline is explained in step 5.
  1. Pick MASONRY TYPE: CMU Block, Brick or Stone. It sets how many units go in a square foot and how far a bag of mortar goes.
  2. Under WALLS, each wall is one line: its length along the face × its height from the top of the footing to the top of the last course. Tap either to enter it.
  3. Tap Add wall for each further wall and enter its length and height. The trash button at the end of the line removes a wall. All the walls are added into one takeoff.
  4. Set DOORS and WINDOWS with − and +. Each one takes a fixed allowance off the wall area. The screen does not ask for opening sizes.
  5. For block, turn on INCLUDE GROUT to get core-fill bags. A GROUT CORES row appears: the percent of cores you will fill, from 5% to 100% in 5% steps. Cells that hold rebar are always grouted solid (IRC R606.3.5.3): with INCLUDE VERTICAL REBAR on and INCLUDE GROUT off, the grout bags are for the bar cells only, and a note under the grout row says so. Turn grout on to fill more cores than that. With both on, the order is the larger of the GROUT CORES share and the bar cells: when the bars need more (close spacing, a low percent), the grout row and BASIS say it was raised to fill every reinforced cell. Turn on INCLUDE VERTICAL REBAR to get bar footage, and pick REBAR SPACING from 8" o.c. to 48" o.c. and REBAR SIZE, #4, #5 or #6. The footage puts a bar at both ends of every wall and one each side of every door and window, full height (IRC R606.12.2.3.3 asks for both in Seismic Design Category C and up). It is a takeoff at the size and spacing you pick, not a design: a foundation wall's bar and spacing come from IRC Table R404.1.1(2)–(4) for its height, backfill and soil, and BASIS & WHAT WAS ASSUMED says so. Neither row shows for Brick or Stone. The calculator never asks the Seismic Design Category, so a CMU card carries an amber line: Category A to C assumed; in D0, D1 or D2 (or a townhouse in C) IRC R606.12 governs the reinforcement.
  6. Set WASTE FACTOR. It is applied to the unit count, the grout and the rebar. Mortar and sand are figured from the unit count, so they carry it too.
  7. Read RESULTS. On the defaults: 198 CMU Block, 6 mortar bags · 18 cu ft sand, 160 sq ft net area.

Reading the results

Masonry results: the answer bar keeps 198 CMU Block and the amber Seismic Design Category line, cut off at C…. RESULTS reads 6 mortar bags · 18 cu ft sand, 160 sq ft net area and the amber Seismic Design Category not asked — A to C assumed; in D0, D1 or D2 (or a townhouse in C) IRC R606.12 governs the reinforcement, then the BASIS & WHAT WAS ASSUMED row and the link Check before you cut · Measure twice. Below, a running-bond elevation 20' 0" by 8' 0" with notes: 160 SF GROSS = 160 SF NET; 198 CMU BLOCK 8x8x16 @ 1.125/SF INCL 10% WASTE; 12 CRS @ 8" · 12 BOND CUTS SHADED; 6 MORTAR ~35/BAG (PREMIX ~12) · 18 CF SAND, and the title strip MASONRY WALL, RUNNING BOND — HALF LAP, NOT TO SCALE. MATERIALS starts with CMU Block 198 pcs and the start of the Mortar row, 6 bags. 8 9 10 11 13
The numbers match the list below.
  1. The headline is the number of units to buy, waste included. It is dimmed and tagged sample until you change an input.
  2. Mortar and sand are on the next line. A grout line and a rebar line, with the spacing, appear only when those options are on. Net area is the wall area after the door and window allowances.
  3. The drawing is a coursed elevation of Wall 1 only. With more than one wall it says WALL 1 OF … SHOWN — TOTALS COVER ALL WALLS. Pinch to zoom and use the expand button for full screen. See Drawings.
  4. The notes under the drawing are where you check what was assumed. BASIS & WHAT WAS ASSUMED states the yields behind them: the area taken off per door and window, units per square foot by type, mortar and grout per bag, and the rebar rule. The first line is the area sum, and it shows what came off for each door and window. The second gives the unit size and the units per square foot used, here 8x8x16 at 1.125/SF, with the waste. The third is the coursing: the number of courses and how many cut units are shaded on the elevation. The fourth gives the mortar basis. For block it reads ~35/BAG (PREMIX ~12): the bag count is for masonry cement mixed with site sand, and premixed mortar lays far fewer block per bag. Brick lays about 120 a bag and stone about 40 (a stone piece takes about three times a brick's mortar), and the materials row says which. Stone is a 12" × 8" ashlar face at 1.5 per sq ft; a yard may sell it by the ton instead. With grout on, a grout line gives its basis the same way: an 80-lb bag yields 0.65 cu ft and an 8" block core takes about 0.26, so about 2.5 blocks a bag. BASIS also says the bond beam drawn in the core detail is not counted, and on a wall over 8' that grout goes in pours of 8' or less (IRC R606.3.5.1) — a single pour over 8' needs 64" lifts and special inspection.
  5. A red coursing note means the wall height is not a whole number of courses and the top course is a cut. It reads FULL CRS + TOP CUT with the size of the cut. Change HEIGHT to a course multiple if you can.
  6. MATERIALS lists the units in pieces, mortar in bags, sand in cubic feet, then grout bags and rebar in lineal feet when they are on (with rebar on and grout off, the grout row says it is for the rebar cells only). With doors or windows it adds one Lintel per opening. Brick and stone are counted as anchored veneer over a backing wall (IRC R703.8): the lintel is a steel angle, L3×3×1/4 cut 3' 8" for the 3' 0" opening the allowances assume (4" bearing each end, Table R703.8.3.1), and Veneer ties are bought at one per 2.67 sq ft (R703.8.4.1) plus six around each opening (R703.8.4.1.1). For CMU the lintel is a count only: a block wall's lintel is sized for the load above it (R606.10), and the row says so. BASIS & WHAT WAS ASSUMED states which of the two the list was built on.
Masonry is a Pro calculator. SHARE PDF and SAVE are Pro as well, a one-time purchase. SHARE PDF and the list icon at its right end stay dim until you have entered your own measurements. SAVE stays lit, but until then a tap only answers Enter your job's numbers first and saves nothing.

Common mistakes