Masonry: bricks, blocks, mortar, grout, ties, joints and lintels

What the masonry calculators cover

A masonry wall is counted unit by unit and then part by part. The unit pages turn a wall area into bricks or blocks, and back, and count the special pieces: bond beam blocks, retaining wall blocks and the glass block panel with its expansion strip and wire. The mortar pages count cement, lime and sand by mortar type, lime mortar by the maker's measured yield, grout for filled cells, thin-bed adhesive for aerated blocks and the bonding cement that is applied to dry-stacked block. The wall parts follow: ties, veneer anchors and weep holes, the shelf angle that carries a veneer, movement and control joints, arches, lintels, parapets and coping.

A last set of pages reads a property or tests a figure against a published method: a brick's initial rate of absorption, a hollow block's equivalent thickness, the self-weight of a block wall, the axial capacity of a short pier, the shear capacity of a wall and the height-to-thickness ratio of a test prism. Chimneys and hearths have two pages of their own, and demolished brick and mortar have conversion pairs between weight and volume.

How the answers are worked out

Units are counted from geometry and not from a fixed rate. The brick calculator derives bricks per area from the nominal face, which is the actual brick plus the joint, and derives the mortar from the gap between the actual and the nominal face across the wall's depth. The block and grout page uses the same nominal-face method, takes grout as the block count times the void volume of a block times the share of cells grouted, and takes face-shell mortar bedding from NCMA TEK 4-2A. The area-to-brick converters are the quick figures: one fixed rate for a standard modular brick and a standard joint, which the page says changes materially with the joint and the brick format.

Mortar follows the proportion specification of ASTM C270, in parts by volume per one part of portland cement, with a band of lime for each of the four types, the midpoint used as the nominal and both ends shown. The sand is bounded between two and a quarter and three times the cementitious volume, so it is an input and not a fixed figure, and the yield is taken as the sand volume, which the page calls a trade convention and not a measured property. Grout follows ASTM C476, fine or coarse, and the page says its slump is deliberately high because absorbent units draw water out after placing, and that its pour lifts follow TMS 602.

Ties and joints follow the documents the pages cite. The wall tie and anchor pages apply the IBC and IRC limit on the wall area one tie may support, with a smaller area in high seismic or high wind conditions and maximum horizontal and vertical spacings that all apply at once. The brick movement joint page states two sources side by side, the Brick Industry Association's Technical Note 18A and the Brick Development Association's guidance citing PD 6697, with the first joint's distance from a corner; the control joint page for block is a commonly used simplified guideline and says that the project's requirements vary with restraint, geometry and the units and mortar.

Units and documents by market

The market setting chooses the system the answers appear in: inch-pound units for the United States, metric for the other three markets, each answer restated in the other system. The mortar bag is the clearest case: a US bag is exact by definition of the sack, while the volume of a metric bag rests on a loose bulk density the page calls an assumption. The table shows which documents the calculators cite for each market, with the United States and the United Kingdom the two that the masonry pages cite most.

Allowance, rounding and repair volume

Counts round up because units, bags and coping lengths are bought whole. The retaining wall block page adds a waste allowance for cuts at ends and corners, the coping page adds one to the parapet length, and the tuckpointing page finds the repair mortar as the length of joint times its width times the raked-out depth, with the bag count from the mortar's yield. The movement joint page counts joints as equal bays over the run, less one, and the sealant and backer rod from the joints times the wall height.

The order the wall is counted in

The groups follow the wall. Count the units first, because the count sets the mortar and the grout. Then the parts that hold the wall to what carries it: ties and anchors from the wall area, weep holes along the base above the flashing, a shelf angle for a veneer, and the joints that let it move. Then the openings, the arch or the lintel and its bearing, and the top of the wall, the parapet and its coping. The property and capacity pages come last, and the chimney, hearth and rubble pages sit apart because they answer their own questions.

What the calculators leave to others

The lintel bearing page gives the minimum bearing length the code figure sets and does not size a lintel, and the lintel capacity page takes an allowable moment you supply. The pier page estimates the allowable axial load of a short unreinforced pier by a simplified expression, and the parapet page applies a widely cited conservative ratio and says the exact limit varies by jurisdiction and seismic category. The anchor embedment page scales a rated capacity from the maker's reference test data and says the approximation does not hold above the tested embedment.

Whole jobs, taken off

A job takeoff asks for the dimensions once and returns every line the job needs, each from its own calculator. These are the ones where masonry is a main line.

• Build a masonry wall

  Units, weeps and what holds the wall, anchors for brick veneer and bond beams and bar for block, with the movement joints each needs.

• Repointing brickwork (tuckpointing)

  Rake out and repoint the joints of a brick wall: the access, the joint length worked from the face, the repair mortar and the frames' mastic.

Read an answer backwards

When you start from what you hold and want to know what it will cover, these pages run the same calculators in reverse.

• How much block wall will my block filler cover?
• How much wall will my bricks build?
• How much wall will my concrete blocks build?
• How long a retaining wall will my blocks build?

Worked examples

A job worked through with its inputs and its working shown, so you can see the figures before you enter your own.

• Brick garden wall

  A brick garden wall on a falling site: the footing steps and concrete, then the bricks, the mortar, the spoil that leaves and the coping, in the order their figures depend on each other.

• Block retaining wall

  A segmental block retaining wall: the blocks, the base stone, the geogrid, the drainage stone and fabric, the heel drain and the trench, from one wall.

• An extension's flank wall, in facing bricks

  Facing bricks for the flank wall of a single-storey extension, 6.5 by 2.6 m

• A batch of Type N mortar, in cement, lime and sand

  Cement, lime and sand for 20 ft³ of site-mixed Type N mortar

Reference tables

• Production rates by operation

  How long each operation takes one person, in person-hours per unit of work.

• Bulk densities of construction materials

  What a cubic metre of loose material actually weighs, in both systems, as this site's calculators compute it.

Guides

The practice behind the numbers: how the work is done, what goes wrong and how to check it.

• Laying Brick and Block

  Every masonry wall is one course repeated: get the unit, its bed, its perpend and its bond right, and the rest is multiplication.

• Estimating Mortar for Walls That Are Not Standard Brick

  Bags per thousand is a coverage rate with the unit size, joint width and bed depth frozen inside it. How to unfreeze it for AAC and dressed stone.

• Building a Brick Veneer Wall That Drains

  A veneer skin is built from the cavity outwards: the anchor grid, the air space and the vent line are all fixed before the scaffold passes them.

• Repointing a Garden or Boundary Wall

  Only a band of a garden wall is usually dead. How to find where it stops, how deep to rake, whether it wants lime, and when to rebuild instead.

• Repointing and Checking a Parapet

  Pricing a repoint from the scaffold: how much joint is really in a parapet, how deep it gets raked, and whether the wall is too slender to leave standing.

• Turning a Brick Arch Over an Opening

  One number — the rise — settles what family the arch belongs to, how hard it pushes sideways, and the taper on every wedge you cut.

• Building a Free-Standing Garden Wall That Stays Up

  A boundary wall is a cantilever held down by nothing but its own weight. Where the piers, the trench width, the DPC and the coping come from.

• Building a Retaining Wall

  A hardscape field guide organised around the two ways retaining walls fail: rotating about the toe, and sliding forward on the base.

• Checking an Old Masonry Wall Before You Load It

  Capacity in old masonry is net area times an allowable stress, and on a standing building neither term can be read off a drawing.

• Cutting an Opening in a Masonry Wall

  Widening an opening is two load questions in order: what each prop holds while the wall is open, and what the angle under the brickwork holds afterwards.

• Replacing a Failed Lintel Over a Window

  A stepped crack off a window corner is not proof the lintel has gone. What separates the five causes, and what holds the wall while one is changed.

• Detailing a Building Expansion Joint

  A separation joint is one plane through a whole building, and it is priced by the piece. What crosses it, who owns each crossing, and what the corners cost.

• Filling a Hollow Wall: ICF Cores and Grouted Block Cells

  A hollow wall gets ordered twice — forms and units by the face, concrete and grout by the void — and only the first number is on the elevation.

Terms

• Mortar designations
• Wall ties and veneer anchors
• Brickwork bond
• Weep holes and cavity drainage
• Lintel and header
• Pointing and joint profile
• Lime binders
• Efflorescence
• Frog and perforations in a brick
• Engineering brick and brick durability grades
• Concrete block
• Coping and capping
• Movement, control and expansion joints
• Spalling and scaling

How the numbers are worked out

Every calculator names the method it uses and the standard or guidance behind it. These are the methods the most of the calculators above rest on, and the published documents they cite.

Methods

• Masonry Units, Coursing and the Things That Support Them

  Why a brick's working size is the unit plus its joint, why a dry brick ruins the mortar bond, and why a veneer's shelf angle is governed by eccentricity rather than by weight. Applies to 7 of the calculators above.

• Unit Conversion, Exactness and Rounding

  Why most conversion factors carry no uncertainty at all, which ones hide a material assumption, and why converting a measurement can never make it more precise than it was. Applies to 6 of the calculators above.

• Quantity, Waste and Rounding

  Why a material count is a ceiling function rather than a division, and why the waste factor — not the geometry — carries the risk. Applies to 5 of the calculators above.

• Section Capacity: Bending, Axial, Shear, and Which One Gives First

  Why depth is worth four times what width is in bending, why reinforced concrete is deliberately designed to fail in the steel rather than the concrete, and why a notch removes far more strength than material. Applies to 4 of the calculators above.

• Thermal and Moisture Movement, and the Joint That Absorbs It

  Why a restrained element's stress is the same whatever its length, why a clay brick outer leaf and a block inner leaf move in opposite directions, and why a joint's width is set by the sealant rather than by the movement. Applies to 4 of the calculators above.

• Mass from Volume and Density

  Why a rolled steel section's mass is read from a table rather than computed, why one material has five densities, and why a tonne of wet sand is less sand. Applies to 3 of the calculators above.

Standards cited

• International Residential Code

  United States. Cited by 3 of the calculators above.

• International Building Code

  United States. Cited by 2 of the calculators above.

• Approved Documents to the Building Regulations (England)

  England (Wales, Scotland and Northern Ireland have their own). Cited by 1 of the calculators above.

• ASTM A615

  Cited by 1 of the calculators above.