Concrete Expansion Joints

Concrete expansion joints are primarily utilised to compensate for expansion and shrinkage in concrete due to temperature changes and other factors.

After concrete is poured and moulded into shape it will harden and set which naturally causes a reduction in volume. Steel reinforcement (within the concrete itself), Granular fill, and adjoining structures can restrain the shrinkage and can lead to tensile stress within the concrete area. Tensile stress can cause the weakest area of the concrete material to crack and that is where expansion joints can assist.

Ableflex Expansion Joints

Ableflex Expansion Joints

If you are looking for a gap filler than Ableflex Expansion Joints are what you need. They are both lightweight and flexible and can be used around curved objects.

Jointex Expansion Joints

Jointex Expansion Joints

Used to seal movement in joins between slabs and other elements. Because they are manufactured from Bitumen, they can be shaped as needed.

Connolly Key Jointing

Connolly Key Expansion Joints

Connolly Key Joints are sturdy and rigid by design and used to deliver straight clean lines. A patented Connolly peg and wedge is utilised to make installs as quick and easy as possible with the added benefit of exact height adjustment.



Used as an alternative to saw cuts in order to induce a full depth crack into concrete. Easy to use, just install a Crack-A-Joint into the wet concrete where you need the joint line.

Joining Concrete Slabs with
Expansion Joints

Utilising Expansion Joints or Control Joints as they are also known, is the most common method for controlling cracking when joining concrete slabs.

Praised for its strength and durability, concrete is one of the most widely used building materials today. However, it can also be prone to expansion.

Expansion Joints are installed at set locations to assist with the creation of a weakened plane where the concrete material is able to crack in a straight line. This creates an aesthetic appearance as the crack occurs underneath the surface of the concrete.

If you are utilising concrete that will join a current structure, you should look to include an expansion joint. This includes, but isn’t limited to, footpaths connecting to a driveway, the junction section of a footpath, the joining of a floor slab to a staircase or column, a building or kerb or any similar construction.

Separate to this, if you have a large slab, expansion joints are required at set intervals. If the slab is unable to be completed in a single pour due to its large size, expansion joints allow the slab to be broken up into individual sections and poured one at a time.

Joining Concrete Slabs

Reduce the Risk of Concrete Cracking
with these Tips

The following tips can be useful for preventing concrete cracking.

  • Thoroughly prepare the site, especially where expansion joints are needed.

  • Ensure any steel reinforcement is properly placed.
  • Verify that Formwork is firm and level.
  • Conduct proper concrete compaction during placement.
  • Utilise an evaporation retardant after screeding.
  • Apply a curing compound.
  • Saw cut the concrete within twelve hours of surface finishing.
  • Saw cut to a depth of 1/3 the thickness of the concrete slab.

  • Ideally, avoid large concrete projects on days with high wind or hot days featuring low humidity.
  • Start early in the morning to avoid the midday sun.
Concrete Slab Cracking

Buy From a Supplier You Can Rely On

We have a thorough range of concrete expansion joints
to serve all of your project needs.

Our team is fully dedicated to providing only the best customer experience, we know that you need a dependable supplier who delivers on time and we pride ourselves on our ability to deliver in this regard.

We take the quality of our products very seriously and you can rest assured knowing we comply with relevant Australian Quality Standards.

  • AS 3600 Concrete Structures, Standards Australia, 2001

Reozone is one of NSW’s leading steel reinforcement suppliers that has been operating out of Western Sydney for over 30 years and we are ready to serve, please contact our professional team today to place your order.

ACRS Steel Certification
QAS International

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