{{ propApi.closeIcon }}
Our industry
Our industry $vuetify.icons.faArrowRight
Economic research and forecasting Economics Housing outlook Tailored market research Economic reports and data Inspiring Australia's building professionals HOUSING The only place to get your industry news Media releases Member alerts Submissions See all
Business support
Business support $vuetify.icons.faArrowRight
Become an apprentice host Hire an apprentice Why host a HIA apprentice? Apprentice partner program Builder and manufacturer program Industry insurance Construction legal expenses insurance Construction works insurance Home warranty insurance Tradies and tool insurance Planning and safety services Building and planning services How can HIA Safety help you? Independent site inspections Solutions for your business Contracts Online HIA Tradepass HIA SafeScan HR Docs Trusted legal support Legal advice and guidance Professional services Industrial relations
Resources & advice
Resources & advice $vuetify.icons.faArrowRight
Building it right Building codes Australian standards Getting it right on site See all Building materials and products Concrete, bricks and walls Getting products approved Use the right products for the job See all Managing your business Dealing with contracts Handling disputes Managing your employees See all Managing your safety Falls from heights Safety rules Working with silica See all Building your business Growing your business Maintaining your business See all Other subjects COVID-19 Getting approval to build Sustainable homes
Careers & learning
Careers & learning $vuetify.icons.faArrowRight
A rewarding career Become an apprentice Apprenticeships on offer Hear what our apprentices say Advice for parents and guardians Study with us Find a course Get your builder's licence Learn with HIA
HIA community
HIA community $vuetify.icons.faArrowRight
Join HIA Sign me up How do I become a member? What's in it for me? Get involved Become an award judge Join a committee Partner with us Get to know us Our members Our people Our partners Mates rates What we do Mental health program Charitable Foundation GreenSmart
Awards & events
Awards & events $vuetify.icons.faArrowRight
Awards Australian Housing Awards Awards program National Conference Industry networking Events Building and Renovation Home Show
HIA products
HIA products $vuetify.icons.faArrowRight
Shop @ HIA Digital Australian Standards Contracts Online Shipping and delivery Purchasing terms & conditions Products Building codes and standards Hard copy contracts Guides and manuals Safety and signage See all
About Contact Newsroom
$vuetify.icons.faMapMarker Set my location Use the field below to update your location
Change location
{{propApi.text}} {{region}} Change location
{{propApi.successMessage}} {{region}} Change location

$vuetify.icons.faPhone1300 650 620

Avoid cracking in concrete paving

HIA’s Building Services team occasionally receives enquiries regarding cracking in concrete paving and how it can be prevented. Enquiries are also asked on what steps can be taken to ensure cracking doesn’t occur post-construction. Depending on the extent of the paving, it can be expensive to repair cracking or to replace and match the concrete paving where it is damaged.

Cracking in concrete paving usually occurs when allowances for shrinkage or general movement of the concrete have not been provided. However, other factors can contribute to the cracking of the concrete, such as:

Adding additional water before placement

A concrete mix is made up of different proportions of cement, water, coarse and fine aggregates and admixtures. Different amounts of each of these ingredients will change the property of the final hardened concrete. For example, adding extra water to a concrete mix that is designed for a specific slump can cause reduced concrete strength, cracking and/or dusting.

Temperature and weather conditions

  • Shrinkage cracks can occur when wind velocity, low relative humidity, high air temperature, or a combination of all three, cause water to evaporate from a concrete surface faster than it can be replaced by bleeding to the surface. The rapid evaporation that causes this cracking can be minimised by windbreaks, shading and efficient curing.
  • Pouring concrete outside the recommended ambient temperatures of between 10°C and 30°C may cause shrinkage cracks, reduce concrete strength and cause crazing or cracking. If pouring outside these temperature parameters, you may need to consider heating or cooling the water or aggregate.

Concrete paving thickness

Cracking may occur if the concrete paving is undersized (in terms of thickness) for the traffic that will use it. AS 3727 Guide to Residential Pavements recommends the following thicknesses for paving.

Traffic Slab Thickness
Foot and bicycle 75mm
Light (cars) 100mm
 Medium 150mm 

How to avoid cracking of concrete paving

Below are some tips for avoiding cracking in concrete paving:

  • Ensure adequate drainage of the subgrade to reduce heaving under slab 
  • Ensure the subgrade is well compacted and at least 75mm thick
  • Provide sufficient contraction joints (usually one-third of the thickness of the slab deep)
  • Provide expansion joints adjoining structures and where the driveways meet the footpath
  • Reduce the evaporation of water from the concrete surface by providing windbreak, shading or efficient curing
  • Start curing as soon as possible and maintain this for an adequate period
  • Adjust the concrete mixture pre-delivery with additives to either slow or quicken the water evaporation time depending on weather and substrate under the concrete pour.

Curing of concrete

Curing is designed to keep the concrete moist by preventing the loss of moisture from the concrete while it is gaining strength. There are a number of ways to cure concrete:

  • Sprinkle the paving with water or cover with wet hessian
  • Use damp straw
  • Cover the slab with damp sand (the sand must be kept moist)
  • Use waterproof paper, or plastic film.

Other concrete defects

Cracking isn’t the only defect that can occur in concrete. Other common defects include:

  • blistering, crazing, curling, delamination, discolouration
  • dusting, efflorescence, low spots, scaling and mortar flaking
  • spalling.

Note that the information above is not exhaustive and includes just some recommendations for avoiding cracking. 

To find out more, contact HIA’s Building Services team.

Email us

Share with your network:

More articles on:

{{ tag.label }} {{ tag.label }} $vuetify.icons.faTimes
Find guides, how-tos, resources and more

Contracts Online 

The industry’s go-to digital platform. 

No matter the size of the job, a watertight building contract is critical to protect your business, and the current climate presents a great opportunity to go digital with your contracts.

Take me there

Business support


Supporting building professionals with custom built services and products.

  • Legal support
  • Contracts Online
  • Host an apprentice
  • Insurance services
  • Managing safety

Explore Business support