Joint repair that moves with the building.
Expansion and movement joints are designed to let a building move — but they are also a primary leak path when their seals fail. We repair and reseal joints in decks, car parks, facades and structures with flexible, watertight systems built to keep moving.
Buildings move. Their joints have to move with them.
Every large structure is designed to move. Concrete expands and contracts with temperature, structures settle, and long spans need somewhere to accommodate that movement without cracking. That somewhere is the movement joint — a deliberate gap, bridged by a flexible sealant or a proprietary joint system that keeps water out while allowing the two sides to move independently.
The problem is that these flexible seals have a finite life. Sealants harden, lose elasticity and split. Joint systems fatigue. And because joints run through the most exposed and highly-stressed parts of a structure — deck expansion joints, car park bays, facade movement joints — a failed joint seal quickly becomes a major leak path.
Repairing a joint is not the same as sealing a static crack. The repair has to accommodate ongoing movement indefinitely, which means the right material, the correct joint geometry and proper detailing at changes of direction and terminations. We specialise in getting joints watertight and keeping them that way.
Movement joints across the building
Expansion joints
Repair and resealing of structural expansion joints in slabs, decks and podiums that have lost their watertight seal.
Car park deck joints
Trafficable, watertight joint systems for car park expansion joints subject to vehicle loading and constant movement.
Facade movement joints
Resealing of vertical and horizontal facade joints where perished sealant is allowing water into the building envelope.
Deck & podium joints
Waterproof joint detailing across balcony, terrace and podium deck junctions integrated with the surrounding membrane.
Construction joints
Sealing of leaking construction and cold joints in below-ground and water-retaining structures.
Sealant replacement
Removal of failed, hardened sealant and installation of correctly specified, high-movement flexible sealant systems.
Getting a joint watertight for the long term
Assess movement & failure
We determine the joint’s movement range and how the existing seal has failed — hardening, splitting, adhesion loss or mechanical damage — which dictates the replacement system.
Remove & prepare
The failed sealant or joint system is fully removed, the joint faces cleaned back to sound substrate, and the correct joint geometry re-established.
Install the system
The specified flexible sealant or proprietary joint system is installed with backing rod and bond breaker to the correct depth-to-width ratio for the movement.
Detail terminations
Corners, changes of direction, drainage points and terminations are detailed and integrated with adjacent membranes — the points where joint repairs usually fail.
What makes a joint repair last
A joint repair that ignores movement is a joint repair that fails again within a season. These are the fundamentals we apply.
- Correct movement capability — the sealant or system rated for the joint’s actual movement range, not just its width.
- Right depth-to-width ratio — backing rod sets the correct sealant profile so it can stretch and compress without splitting.
- Bond on two faces, not three — a bond breaker prevents the sealant tearing itself apart as the joint moves.
- Integrated with the membrane — joints tied into the surrounding waterproofing so water can’t bypass the repair.
Joint Repair FAQs
Usually because the original installation ignored movement fundamentals — wrong sealant type, incorrect depth, no bond breaker, or a sealant not rated for the joint’s movement range. A joint that moves more than its seal can accommodate will always split. We diagnose why the previous seal failed and install a system matched to the actual movement.
Yes. Trafficable expansion joints require purpose-designed systems that are watertight, flexible and able to carry vehicle loading. We install proprietary trafficable joint systems suited to car park decks, integrated with the surrounding deck membrane.
The leak itself is a waterproofing problem, but persistent water through a joint can corrode reinforcement and degrade the structure over time. The joint is doing its structural job by allowing movement — it just needs its watertight seal restored. If there is evidence of underlying structural distress, we would flag that for engineering assessment.
Yes. On decks, balconies and podiums, joints are part of the overall waterproofing system. When we remediate a deck, joint detailing is integrated with the membrane so there is continuous protection across the whole surface, including the moving junctions.
Explore related work
Reseal a failing joint
A perished joint seal is an open door for water. Book an assessment and we’ll install a flexible system that keeps moving with your building.