Slip Joint — Sliding Joint for Brick Veneer Construction, Sydney

What is a Slip Joint?

A slip joint, also called a sliding joint, is a galvanised steel masonry accessory used in brick veneer wall construction to accommodate vertical movement between the brickwork and the structural frame behind it.

Brick veneer walls are tied to a structural frame but are not rigidly connected at every level; they need to be free to move vertically as the frame deflects under load or as the slab edges move over time.

Without a slip joint at the correct locations, that differential movement causes the brickwork to crack. The slip joint provides a deliberate break in the mortar bed at specified courses, allowing the brick leaf to slide vertically without the movement being restrained or transferred into the structure above.

Slip joints are a mandatory requirement in brick veneer construction under AS3700 (Masonry Structures) and are specified by engineers and architects on all compliant brick veneer projects in Australia. They are manufactured from galvanised steel and installed as a folded section across the full width of the mortar bed, with one leg embedded in mortar and the slotted leg left free to permit movement.

Specifications

Contact our Dural team at (02) 9651 1055 to confirm current stock, sizes, and compatibility with your wall system.

What is a Slip Joint Used For?

A slip joint is used in brick veneer wall construction wherever the brickwork needs to be isolated from vertical movement in the structural frame. AS3700 requires slip joints at specific locations in all compliant brick veneer construction.

At Floor Slab Edges

The most common installation location. A slip joint is installed in the mortar bed at the level of each floor slab edge, allowing the brick leaf above to move independently of the slab below. Without this, slab deflection under load transfers directly into the brickwork and causes horizontal cracking.

Works alongside: Brick Common, Tie Veneer, Bitumen Joint

At Window and Door Heads

Slip joints are required above lintels and window frames in brick veneer construction, providing a break between the brickwork bearing on the lintel and the wall above. This prevents load from being transferred into the window or door frame.

At Roofline Level

At the top of a brick veneer wall where the wall meets the roof structure, a slip joint allows the roof to move independently of the brickwork; important in timber-framed construction where roof deflection under live load is expected.

In Hebel Block Walls

Slip joints are also used in autoclaved aerated concrete (AAC) wall systems at slab interfaces and panel junctions to manage movement. The same vertical movement requirement applies to Hebel block construction as to traditional brick veneer.

Works alongside: Hebel Block, Bitumen Joint, Building Materials range

Slip Joint vs Control Joint: What's the Difference?

A control joint is a vertical break through the full thickness of a masonry wall, designed to accommodate horizontal thermal and moisture movement in the wall plane. Control joints run vertically and are typically filled with a flexible sealant.

A slip joint is a horizontal break in the mortar bed, designed to accommodate vertical movement between the brick leaf and the structural frame behind it. Slip joints run horizontally at specified course levels and use a folded galvanised steel section rather than sealant.

Brick veneer construction requires both control joints for horizontal movement and slip joints for vertical movement.

What is a Slip Joint Not Suitable For?

A slip joint is not a damp-proof course or waterproofing membrane. It manages structural movement only; it does not prevent moisture from tracking through the mortar bed. A bitumen joint or DPC is required separately at locations where moisture exclusion is also needed.

Slip joints should not be substituted for control joints in locations requiring horizontal movement accommodation. The two products perform different functions, and both are required in compliant brick veneer construction.

Not sure what's required at a specific location on your project? Call our team at Martins (02) 9651 1055; we've been helping builders and bricklayers across Sydney get the right product since 1970.

Martins Building & Landscape Supplies has supplied Sydney builders, bricklayers, and concreters with masonry accessories and building products since 1970. We stock slip joints and the full range of masonry and building materials you need to complete a compliant brick veneer job.

Pick up from our Dural yard — 272–274 New Line Road, Dural NSW 2158
Mon–Fri: 6am–5pm | Sat: 6:30am–2pm | Closed Sundays and Public Holidays

Sydney delivery available — same-day subject to availability.

Call us to confirm: 📞 (02) 9651 1055

Frequently Asked Questions