CPC33020 Bricklaying flashcards

33 cards. Read the term and the definition here. The deck at the top of this page is optional.

Stretcher bond

A bond in which all bricks are laid lengthwise as stretchers with each course offset by half a brick, giving a half-brick overlap. It is the most common bond for single-skin walls.

English bond

A bond made up of alternating courses of headers and stretchers. It is strong and used where thick, load-bearing walls are required, but it is slower to lay than stretcher bond.

Flemish bond

A bond in which each course alternates a stretcher and a header brick. It provides good appearance and strength but requires more cutting and is slower than stretcher bond.

Perpend joint

The vertical mortar joint between the ends of adjacent bricks in the same course. It is normally 10 mm thick and must be fully filled for structural and weathertight performance.

Bed joint

The horizontal mortar layer on which a course of bricks is laid. Standard thickness is 10 mm, and it transfers compressive load between courses while accommodating minor irregularities.

Course height formula

The height of one brick plus one joint gives the course module. For a 76 mm brick with a 10 mm joint, each course adds 86 mm, so a 2.4 m wall needs 28 courses.

Bricks per square metre

For 230 x 76 mm bricks with 10 mm joints, the module is 240 x 86 mm. One square metre divided by 0.24 x 0.086 gives approximately 48.5 bricks per square metre.

Mortar mix 1:1:6

One part cement, one part lime and six parts sand by volume. This general-purpose mix suits normal brickwork and balances workability with moderate strength and durability.

Mortar working life

The period after gauging during which mortar remains usable, commonly about two hours in hot weather. Mortar beyond its working life must be discarded, not revived with extra water.

Sand bulking

Damp sand occupies more volume than dry sand because moisture separates the grains. Volume batching must allow for bulking or the mix will contain too little sand and be over-rich.

3:4:5 square check

A setting-out method using a triangle with sides in the ratio 3:4:5, which always has a right angle between the short sides. It confirms corners are square before laying begins.

Gauge rod

A marked vertical staff showing each course level, set up at the corner of the work. It lets the bricklayer keep bed joints level and course heights consistent across the wall.

Line and pins

A taut string held between pins or blocks at each end of a course. It gives a straight reference for the brick face and must be checked for sag on long walls.

Face brick selection

Face bricks are chosen for appearance, with consistent colour, texture and dimensions. Chipped or discoloured units are set aside or used where they will not be seen.

Toothing and racking

Methods of leaving a wall end for later continuation. Toothing leaves alternate bricks projecting; racking leaves a stepped diagonal edge. Racking is faster and gives a stronger joint.

Cavity wall tie spacing

Wall ties are typically fixed at 600 mm horizontal and 450 mm vertical centres. Extra ties are required near openings and free edges to transfer lateral loads to the inner leaf.

Weephole placement

Small open joints left in the outer leaf to drain moisture from the cavity. They are placed at maximum 1200 mm centres, above flashings and at the base of the cavity.

Damp-proof course lap

A DPC is lapped at least 100 mm at joints and must be continuous across the wall. It projects past the outer face to form a drip that keeps water off the masonry below.

Cavity flashing

An impervious membrane at the base of the cavity that collects water and directs it to the weepholes. It is turned up against the inner leaf and lapped over the DPC.

Segmental arch rise

The vertical height of an arch above its springing line. As a rule the rise should be at least one-eighth of the span to keep the arch stable under load.

Voussoir

One of the wedge-shaped bricks or stones forming the curved part of an arch. Voussoirs are equal in size and their joints radiate from the centre of the arch.

Lintel bearing length

The distance a lintel rests on masonry at each end, generally at least 150 mm unless the engineer specifies otherwise. Adequate bearing spreads the load into the wall.

Control joint spacing

Vertical joints that allow movement in masonry, typically spaced 6 to 8 metres in unrestrained clay brickwork. Closer spacing is used for long, thin or movement-prone walls.

Movement joint function

A joint that accommodates expansion or contraction of the masonry without cracking. It must be kept free of mortar and sealed with a flexible backing rod and sealant.

Scaffold guardrail heights

Guardrails are fitted at approximately 900 mm and 1800 mm above the platform, with a toe board at least 150 mm high. The platform itself must be at least 450 mm wide.

Respirable crystalline silica

Fine dust from cutting bricks or concrete that can damage lungs when inhaled. Control it with water suppression or extraction and wear appropriate respiratory protection.

Manual handling control

Bricks and blocks are heavy, so handling is managed by mechanical aids, team lifting and keeping loads close to the body. Repetitive bending is reduced by working at correct bench height.

Fire resistance level

A rating expressed as three numbers for structural adequacy, integrity and insulation, such as 60/60/60. It states the period in minutes a tested element resists fire.

Brick veneer construction

A single outer leaf of bricks tied to a timber or steel frame with a cavity between. The brickwork carries only its own weight and provides weather protection and appearance.

Reinforced brickwork

Masonry strengthened with steel reinforcement placed in bed joints or grouted cores. It is used where tensile or lateral loads exceed the capacity of unreinforced brickwork.

Efflorescence

A white salt deposit on the brick face caused by moisture moving salts to the surface. It is usually brushed off dry and does not indicate structural failure of the masonry.

Clean-down of brickwork

Removing mortar smears and stains after laying, using a stiff brush and clean water or approved acid wash. Cleaning too early or too harshly can damage the brick surface.

Damp-proof membrane

An impervious layer placed under a slab or in a wall to stop moisture rising into the building. It must be continuous, lapped correctly and protected from damage during construction.