CPC33020 Bricklaying key terms

A horizontal layer of brickwork or blockwork of consistent height, built as one operation before the next layer is added. Courses are measured in millimetres and set the module for the whole wall.

The horizontal layer of mortar on which a brick or block is laid. Its thickness controls course height and must stay consistent to keep the wall level and true.

The vertical mortar joints between adjacent bricks or blocks in the same course. They are filled fully and kept uniform in width to spread load and prevent water penetration.

Another name for the vertical joint separating two units along the length of a wall, formed where one brick or block meets the next end to end in the same course.

The vertical spacing between successive bed joints, usually set by a gauge rod or storey pole. Consistent gauge keeps courses level around the building and matches openings and fixings.

A marked timber or metal batten showing course heights, sill and lintel levels for a job. It is set up at corners so every course lines up around the whole structure.

The planned arrangement of bricks or blocks so that vertical joints in one course do not line up with those in the course above, tying the wall into one strong unit.

A bonding pattern where every unit is laid lengthwise along the wall face, with each course offset by half a unit so vertical joints are staggered between courses.

A brick or block laid so its shorter end face shows on the wall surface, used to tie two leaves of a wall together or to form decorative and strengthening patterns.

A brick or block cut to half its normal length, used to start or finish a course so the bond is maintained and joints are staggered correctly.

The distance one unit extends past the joint below it, expressed as a fraction of unit length. Adequate overlap is what gives a bonded wall its strength.

The vertical joint running lengthwise between the inner and outer leaves of a cavity or thick wall. It is filled with mortar or grout to tie the leaves together.

A wall built as two separate leaves with a gap between them. The cavity stops moisture crossing to the inner leaf and improves thermal and acoustic performance.

A corrosion-resistant metal fitting built into both leaves of a cavity wall to hold them together. Ties are spaced at set centres and must slope slightly to shed water inward.

A mix of sand, cement, lime and water used to bed and joint masonry units. Its strength, workability and colour depend on the proportions chosen for the job.

The stated proportion of cement, lime and sand by volume in a mortar, such as 1:1:6. The ratio determines strength, durability and flexibility for a given exposure condition.

An additive or lime content that makes mortar easier to spread and improves its workability without adding extra water, helping units bed down evenly and stick to the mix.

A strip of impervious material such as metal or plastic built into masonry at junctions and openings to divert water out of the wall rather than letting it soak inward.

A small open joint or tube left in the outer leaf just above flashing so water collected in the cavity can drain out. Weep holes must stay clear of mortar droppings.

A continuous impervious layer built into a wall, usually near ground level, that stops moisture rising from the ground into the masonry above by capillary action.

A sheet material laid under a concrete slab or floor to prevent ground moisture entering the building. It is lapped and sealed, and turned up at edges where required.

A horizontal structural member spanning an opening in a wall to carry the masonry above it. It may be steel, concrete, timber or a reinforced masonry unit.

The length of a structural member such as a lintel or beam that rests on supporting masonry at each end, spreading the load safely into the wall.

A gap left in a wall for a door, window or service penetration. Openings need accurate setting out, adequate bearings and correct lintel and flashing details.

Marking the position of walls, corners and openings on the ground or slab before bricklaying starts. Accurate setting out ensures the building matches the drawings and is square.

A fixed reference level or line from which heights and positions are measured on site. Datums are carried from benchmarks so floors, courses and openings align throughout the job.

A horizontal board fixed on stakes at the corners of a building, marked with the wall lines and used with string lines to control setting out and keep walls straight.

A taut cord stretched between two points to give a straight edge and constant level for laying courses. Bricklayers line and level each course against it as they build.

The condition of being truly horizontal, checked with a spirit level or laser. Each course must be levelled across its length and around corners to avoid cumulative error.

The condition of being exactly vertical, checked with a spirit level or plumb rule. Walls, reveals and corners must be plumb for the full height of the work.

A corner or setting-out line at exactly 90 degrees, checked with a builder's square or the 3-4-5 method. Square corners keep the building rectangular and rooms true.

Finishing the exposed face of mortar joints by tooling them to a chosen profile. Correct pointing compacts the mortar, improves weather resistance and gives a neat appearance.

Working the surface of a mortar joint with a jointer or trowel while the mortar is firm, compacting it against the brick edges and forming the finished joint profile.

A white powdery deposit of soluble salts carried to the surface of masonry by water and left behind as it evaporates. It is usually brushed off and does not affect strength.

A metal anchor used to secure a non-structural masonry leaf to a structural frame or backing wall, allowing movement while resisting lateral loads such as wind.

A deliberate vertical gap in a wall that lets masonry expand and contract with temperature and moisture without cracking. It is filled with a compressible backing and sealant.

A single outer leaf of brickwork tied to a framed structure, providing a weather-resistant decorative facing while the frame carries the structural loads.

Masonry built from concrete or similar blocks, usually larger and faster to lay than bricks. Blocks need accurate bedding and are often used for internal and backing walls.