Building components · Wall Leaves & Backing
Masonry Course
Explains the course as the increment by which a masonry wall is built and measured, distinct from the bond that arranges the courses and from the leaf they build up.
Educational reference entry. What this element has to do, and whether any particular arrangement of it is adequate, depends on the whole assembly, the loading, the exposure, local requirements, the manufacturer's instructions and qualified professional design.
Overview
What a course is
A course is a single row of units laid at one level across a wall. Masonry is built course by course, and almost everything else about a wall — its bond, its levels, where a barrier or a tie sits, where an opening starts — is described in terms of which course it happens at.
The course is also the unit of overlap. Each course sits across the joints of the one below it, and that offsetting is what turns a stack of separate units into a wall that acts together. A row of units that did not overlap the row beneath would still be a course, but it would not be doing the structural work a coursed wall depends on.
Boundaries
How it differs from nearby elements
The distinctions that keep this entry from being a restatement of its neighbours.
- It is not a laying course. A laying course is the thin bedding layer beneath paving units that lets them be brought to level; a masonry course is a row of units within a wall, and the two belong to entirely different assemblies.
- It is not a leaf. A leaf is one complete skin of a wall over its full height; a course is one horizontal increment of it, and a leaf is built from many courses.
- It is not a bond. A bond is the pattern by which successive courses overlap one another; the course is the row itself, and the same course can appear within several different bonds.
Terminology
Common names and aliases
These names describe the same element. The library keeps one entry per component so that a trade term or a regional name never becomes a second, thinner page.
- brick course
- block course
Dependencies
What it depends on
What has to be right elsewhere for this element to do its job.
- The bed joint beneath it, which is what it is levelled on and what carries its load into the course below.
- The bond, which determines how far it overlaps the course beneath and therefore how the wall acts as one element.
- The units being consistent enough for the coursing to stay true, since variation accumulates as the wall rises.
- How it is tied or bonded to anything running into it, such as a returning wall, a pier or a second leaf.
Considerations
Topics that genuinely apply here
Subjects worth discussing about this element. These are discussion topics, never measured values, ratings or performance claims.
Overlapping courses are what allow load applied at one point to spread as it travels down a wall, which is why bonding is structural rather than decorative.
Coursing is cumulative: small differences at each course add up over the height of a wall, and they are most visible where a wall has to meet a fixed level such as a sill or a head.
Exposure varies up a wall, and courses at the base and at the top of a wall commonly weather differently from those between them.
Positions within masonry are frequently recorded by course rather than by dimension, so knowing which course something sits at can matter more than knowing its height.
Materials
Commonly formed from
Material families this element is commonly realised in. This states common practice only — it is not a statement that any of these materials suits this component in a particular building, which depends on the whole assembly and on qualified review.
Materials
Commonly incorporates
Materials this element commonly contains as a distinct constituent part, rather than being made of.
Assemblies
Building systems this element is met in
The role this component fills inside each assembly. A role describes what the element does there — it is not a statement that this component suits that system in any particular building.
Related elements
Neighbouring components
Typed relationships to other elements. There is deliberately no generic “related” category: an edge that cannot be classified does not exist.
Narrower forms of this element
Clarifications
Commonly misunderstood
- That a course is simply a row of bricks. It is the increment the whole wall is set out and controlled by, including the levels at which openings, barriers and restraints occur.
- That any row of units bonds a wall. Bonding depends on the overlap between courses, and a pattern with little or no overlap gives the wall much less of the continuity a bonded wall relies on.
Conversations
Questions for qualified professionals
Questions worth asking someone with the project in front of them. This page cannot answer them.
- What bond is this wall built in, and what overlap does it give between courses?
- At which course do the barriers, restraints or supports in this wall sit?
- How is the coursing being controlled so it arrives level at the openings and at the top of the wall?
- Where a returning wall or pier meets this one, are the courses bonded together or simply built against each other?
Go deeper
Related Build Design Hub guides
Planning guidance behind the decisions this element involves.
Preparation
Related planning checklists
Owner-side preparation before the conversation where this element comes up.
What this entry does not do
- This entry describes a position in a wall. It states no course height, no unit size, no bond specification and no number of courses, and none can be inferred from it.
- Whether the bonding in a particular wall is doing what its design assumed is a structural question that cannot be answered from a reference entry.
Wall Leaves & Backing
The distinct vertical layers that make up a wall — outer and inner leaves, the cavity between them, and the backing that supports what is fixed to the face.
Browse all wall leaves & backing entries →