Key takeaways
- Movement joints exist to break a masonry wall into panels short enough that accumulated expansion and contraction cannot crack the brickwork or the finishes around it.
- Wall ties must be matched to the substrate and the cavity width, because stiffness, drainage and corrosion protection differ between a timber frame, a steel frame and a concrete slab edge.
- Articulation is the whole detail, not just the joint: the frame, the slab, the roof line and the abutting finishes all have to allow the same movement the joint allows.
- Defects from restrained or missing movement present as stepped cracking and moisture entry, and by the time they are visible the repair usually involves rebuilding a panel rather than patching it.
- Movement and articulation details belong on the drawings and in the inspection record, because rectification is a builder cost and the evidence trail is what decides who pays.
Brickwork is a rigid material sitting on a structure that is not. Clay masonry expands slowly over its life as it takes up moisture, concrete shrinks and moves with temperature, timber frames shrink and move with moisture content, and the whole assembly moves with the slab beneath it. None of that is a fault. It is normal behaviour that the detailing has to accommodate, and movement joints, ties and articulation are the three parts of that accommodation.
Get it right and nobody notices. Get it wrong and the wall tells you, usually a year or two after practical completion, in the form of stepped cracking through the brickwork, a horizontal crack at a slab edge, or water finding its way into a cavity that was supposed to drain. The Building Commission NSW maintains a building defects library that records the defect types that keep recurring in NSW, and masonry cracking and moisture entry sit firmly in that recurring group.
This article deals with movement and articulation in masonry walls: how joints are spaced and formed, which tie suits which substrate, and how the junctions around a panel have to be detailed so the joint actually does its job. It does not cover structural design of the wall itself, and it does not replace the design documentation for a specific job.
Why masonry needs somewhere to go
Every material in a wall assembly changes dimension over time, but they do not change together. Clay bricks gain moisture and expand; concrete blocks and concrete slabs shrink as they cure and then move with temperature; timber frames shrink as they dry and swell when they get wet. If those movements are locked together by continuous masonry, rigid ties and stiff junctions, the resulting stress has to be relieved somewhere, and the relief point is a crack.
A movement joint is a deliberate, controlled break in the masonry. It divides a long elevation into panels short enough that the movement within each panel is small, and it gives each panel a free edge to move towards. A joint is not a gap left for looks, and it is not a substitute for a control joint in a slab. It is part of the wall design.
The spacing between joints depends on the masonry type, the exposure, the colour and absorbency of the units, the amount of reinforcement, and the restraints on the wall. Because it depends on those variables, the spacing for a given job comes from the design documentation and the masonry standard that applies, not from a rule of thumb carried between jobs. Where a builder is working without a nominated spacing, the right move is to get one in writing before the first course goes down, because retrofitting a joint into a completed wall is a rebuild, not a repair.
Where movement joints belong in an elevation
A movement joint has to run the full height of the panel it serves, from the base of the wall to the top, without being stopped by a lintel, a slab edge or a change in the wall’s function. A joint that stops short simply moves the stress to the point where it stops.
Joints are commonly needed at changes in wall height, at changes in wall thickness, at junctions between different masonry types, at re-entrant corners and returns, and where a long wall meets a rigid element that will not move with it. The joint should be set out on the elevation before bricklaying starts so it lands where the design intends, not wherever the wall happens to end on the day.
Forming the joint is as important as placing it. The gap must be kept clear of mortar droppings, brick offcuts and ties, because anything bridging the gap re-couples the panels and defeats the purpose. The backing and sealant system has to suit the joint width and the exposure, and the sealant has to be installed to the profile the manufacturer requires, not simply gunned in and struck off.
Movement joints are not the same as control joints
The two terms get used loosely on site and that causes real confusion. A movement joint is a break in the masonry itself. A control joint is a deliberate line of weakness in a concrete slab or pavement that controls where cracking occurs in that element. They serve different materials and different purposes, and one does not substitute for the other.
The connection between them is that slab movement feeds into the wall above. If the slab shrinks or moves and the masonry is tied rigidly to it without articulation, the wall absorbs the movement and cracks. That is why the slab detail and the wall detail have to be read together. The PointCPD article on strip footings and pad footings on residential jobs in NSW covers the footing side of that load path.
Sequencing movement joints into a masonry wall
- 1Set out the panelDivide the elevation into panels at the spacing the design nominates, before any brick is laid, so joints land on the grid rather than being invented on the day.
- 2Form the jointBuild a clean, full-height break with the correct backing and sealant system, kept free of mortar droppings and brick ties across the gap.
- 3Fix the tiesInstall ties at the spacing and embedment the design requires, matched to the substrate, and keep them clear of the joint.
- 4Articulate the junctionsDetail the head, sill, slab edge and abutting elements so they can move with the frame rather than locking the panel up.
- 5Inspect and recordPhotograph the joint, the ties and the articulation details before the cavity is closed and the wall is lined.
Wall ties: matching the tie to the substrate
A wall tie does two jobs. It transfers lateral load from the outer leaf to the structural backing, and in a cavity wall it allows the outer leaf to move slightly relative to the frame while keeping the cavity intact. Those two jobs pull in different directions, which is why tie selection is a design decision rather than a stock item.
The tie type depends on the substrate. A timber frame, a steel frame and a concrete or masonry backing each require a different fixing, and a tie that is right for one is wrong for another. Cavity width matters too: the tie has to span the cavity actually built, not the cavity shown on an early drawing, and it has to sit at the correct fall so any moisture that reaches it runs back to the outer leaf rather than into the frame.
Spacing and embedment come from the design and the relevant masonry standard. Ties that are too few, too short, driven in at the wrong angle or fixed only to one leaf do not carry the load they were specified for, and the failure shows up as bulging or cracking rather than a clean break. Corrosion protection also matters, particularly on coastal sites and in exposed locations, and the tie specification should reflect the exposure of the actual site.
Ties at movement joints
Ties should not cross a movement joint. A tie bridging the joint restrains the panel movement the joint was built to allow, and the joint then functions as a crack initiator rather than a relief point. On the other side of the joint, ties continue at the normal spacing.
Ties at openings
Openings concentrate stress. The masonry around a window or door needs ties at closer spacing than the general field of the wall, and the articulation at the head and sill has to allow the frame and the masonry to move independently. A lintel bearing hard onto masonry with no allowance for movement, combined with a frame installed tight, is a common source of cracking at the corners of openings.
Articulation: the detail around the joint
A movement joint on its own does not articulate a wall. Articulation is the whole set of details that let the building move without transferring that movement into the masonry. It includes the joint itself, the tie fixings, the head and sill details, the slab edge, the roof connection and the junctions with any abutting element such as a different cladding, a concrete column or a retained wall.
The test is simple to state: trace the movement path from the panel to the structural frame and ask whether anything along that path is rigid in the direction the movement needs to go. If something is, that element will either crack, or it will transfer the movement somewhere less able to take it.
Head details are a common failure point. A masonry panel under a slab or a beam needs a slip or articulation detail that allows vertical and horizontal movement without the panel bearing hard against the structure above. Sill details need the same treatment at the bottom, particularly where the panel sits on a slab edge that will move.
Where two different materials meet, the junction has to be detailed rather than caulked and hoped for. A masonry wall abutting a concrete column, a steel post or a different cladding system needs a joint that accommodates the differential movement between the two, with the correct backing and sealant, and with the ties detailed so they do not lock the two together.
Before the cavity closes, check these
- Movement joints are full height and free of mortar, offcuts and dropped ties.
- Joint spacing matches the design on the current drawings, not the last job.
- Ties are the correct type for the substrate and the cavity width actually built.
- Ties are fixed at the required spacing and embedment on both leaves.
- Weepholes and the base of the cavity are clear so water can drain.
- Articulation at the head, sill and slab edge allows movement rather than restraining it.
- Joints and ties are photographed with the location marked before lining.
What goes wrong, and when it surfaces
Movement-related defects rarely appear at handover. Clay masonry continues to expand for years, concrete continues to shrink, and frames continue to move with the seasons. The typical pattern is a wall that looks fine at practical completion and shows stepped cracking, a horizontal crack at a slab edge or a diagonal crack from the corner of an opening somewhere in the first few years of occupation.
Once cracking opens, moisture follows. Water enters the crack, saturates the masonry, and then either tracks into the cavity or through to the internal lining. At that point the defect is no longer cosmetic. Building Commission NSW research into serious defects in NSW strata communities has consistently identified water ingress and cracking among the defect categories that generate the largest rectification bills, and the pattern is the same in detached residential work, just at a smaller scale.
The commercial reality is that by the time a movement defect is visible, the cheap fix has usually gone. Patching a crack with sealant does not restore the joint that was never built, and if the wall is restrained the crack will reopen. A proper rectification typically means cutting a movement joint into the wall or rebuilding the affected panel, then making good the internal linings, the finishes and any cabinetry or tiling that has to come out to get at it.
Who pays depends on the evidence. If the movement joints, tie types and articulation details were documented on the drawings and the wall was built to them, the builder has a defensible position, and the issue is more likely to sit with a design or product question. If the details were never documented, or were documented and not followed, the cost lands with the builder. That is why the record matters as much as the work.
Worked example: a two-storey brick veneer in western Sydney
A builder in western Sydney completes a two-storey brick veneer home on a concrete slab with a timber frame. The lower level is long, with a garage projecting forward and a return where the garage meets the main elevation. At practical completion everything looks clean. Around eighteen months later the owner reports a stepped crack running diagonally from the corner of the garage return, and a smaller horizontal crack under the upper floor slab edge on the same elevation.
On inspection, the elevation has no movement joint anywhere along its length. The bricklayer laid continuously from the garage corner to the far end because that is how the drawing showed it — the drawing showed the wall, the openings and the ties, but no joint and no articulation note at the slab edge. Ties at the return are standard cavity ties at the general spacing, with no closer spacing at the re-entrant corner. The upper floor slab edge bears directly on the masonry with no slip detail.
Three separate mechanisms are at work. The long panel has nowhere to relieve its own expansion, so it has cracked at the point of highest restraint, the re-entrant corner. The slab edge has locked the upper panel to the frame, so slab movement has transferred into the masonry. And the corner itself has concentrated the stress because the ties there are no closer than anywhere else.
The rectification is not a patch. A movement joint has to be cut into the elevation at the position the design should have nominated, which means cutting through the brickwork full height, installing the backing and sealant system, and making good the internal linings on the affected section. The slab edge detail has to be reworked to allow movement. The corner ties are effectively inaccessible without removing brickwork, so the practical option is to address the joint and the slab edge and monitor the corner.
The lesson is in what was missing from the documentation, not in how the bricklayer laid the wall. The bricklayer built what was drawn. The builder carries the cost because the articulation detail was never resolved before the first course went down, and there is no inspection record showing otherwise.
Getting the detail right before bricklaying starts
The window to fix movement detailing is before the first course, and it closes fast. The setout has to be on the elevation, the joint positions marked, the tie types and spacing confirmed against the substrate actually used, and the head, sill and slab edge details resolved on paper. On a job where the design is silent, the builder should seek written confirmation of the joint spacing, tie type and articulation details from the designer and keep that confirmation on file.
During construction, the practical controls are simple. Keep the joints clear of mortar and offcuts. Keep ties out of the joints and at the specified spacing and embedment. Photograph the joints, the ties and the articulation details before the cavity is closed and the wall is lined, with the location identifiable in the frame. That record is what a certifier, an insurer or a regulator will ask for if a defect is alleged later, and it is far cheaper to build than to reconstruct.
Masonry defects also sit inside the statutory warranty regime for residential work in NSW, which is why the evidence trail matters commercially as well as technically. The NSW Government guidance on keeping new work trouble-free and the warranties that apply is worth reading alongside the Building Commission NSW building defects library, because the two together show which defect types generate claims and how long a builder remains exposed to them.
For builders working through their CPD obligations, movement and articulation detailing is a topic that repays the time because the defect cost is so disproportionate to the detailing cost. The guide to how NSW builder CPD works sets out how the requirement is structured, and the PointCPD course catalogue lists the courses that cover masonry, structural and defects topics.
What to check on the next job
Before bricklaying starts, confirm that the elevation shows movement joint positions and that the spacing is nominated in the design documentation. Confirm the tie type against the substrate and the cavity width actually built, and confirm the spacing including any closer spacing at openings and returns. Confirm the head, sill and slab edge details allow movement rather than restraining the panel. Confirm the joint backing and sealant system suits the joint width and the exposure of the site.
During bricklaying, hold the setout, keep the joints clear, keep ties out of the joints, and photograph everything before it is covered. After completion, keep that record with the job file. None of it is difficult, and all of it is cheaper than the alternative.
Questions builders ask
How far apart should movement joints be in a brick wall?
The spacing depends on the masonry type, the exposure, the amount of reinforcement and the restraints on the wall, so it comes from the design documentation and the applicable masonry standard rather than a fixed rule. If the drawings do not nominate a spacing, get it confirmed in writing by the designer before bricklaying starts. Cutting a joint into a completed wall is a rebuild, not a repair.
Can a movement joint double as a control joint in the slab?
No. A movement joint is a deliberate break in the masonry that lets the panel move; a control joint is a line of weakness in a concrete slab or pavement that controls where that element cracks. They serve different materials and different purposes. The two details still have to be read together, because slab movement transfers into the wall above unless the junction is articulated.
Should wall ties cross a movement joint?
No. A tie bridging a movement joint restrains the panel movement the joint was built to allow, and the joint then acts as a crack initiator rather than a relief point. Ties continue at the normal spacing on each side of the joint. The joint itself must also be kept clear of mortar droppings and brick offcuts, because anything bridging the gap re-couples the panels.
How do I choose the right wall tie for the job?
The tie type depends on the substrate — a timber frame, a steel frame and a concrete or masonry backing each need a different fixing — and on the cavity width actually built, not the width shown on an early drawing. Ties also have to be set at the correct fall so moisture runs back to the outer leaf. Corrosion protection should match the exposure of the actual site, particularly on coastal work.
Why has my brickwork cracked a year after completion?
Movement-related cracking rarely appears at handover. Clay masonry continues to expand over years, concrete continues to shrink, and frames move with the seasons, so the typical timing is a stepped crack, a horizontal crack at a slab edge or a diagonal crack from an opening corner somewhere in the first few years. Once the crack opens, moisture follows, and the defect stops being cosmetic.
Who pays to fix a movement joint that was never built?
It usually comes down to the evidence. If the joints, tie types and articulation details were documented and the wall was built to them, the builder has a defensible position. If the details were never documented, or were documented and not followed, the cost generally lands with the builder. Photographs of joints, ties and articulation details taken before the cavity is closed are the record that decides the question.
Sources
- Building Defects Library · Building Commission NSW · 2025-06-25
- Research on serious building defects in NSW strata communities · Building Commission NSW · 2026-04-28
- Ensure your new work remains trouble-free (defects and warranties) · NSW Government
- Survey shows serious defects down in newer apartment buildings · Building Commission NSW · 2023-12-15
Published 29 July 2026. General information for builders, not legal, financial or engineering advice for a specific job. Check current requirements with the relevant regulator or standard before relying on them.
