Is your foundation sinking? Do you have cracks in your walls or floors? If so, you may need underpinning.

Underpinning is the process of strengthening or repairing a foundation that is unstable or damaged. It's a complex job made easy by experienced tradies. It's also essential if you want to protect your home from further damage.

Keep reading to find out everything you need to know about underpinning, including:

• What is underpinning and why is it important?
• The most common issues requiring underpinning
• The cost of hiring an underpinning business
• How to hire a reputable local underpinning expert
• Licensing requirements for underpinning experts
• Benefits of hiring an underpinning expert
• Getting quotes from underpinning experts

What does an underpinning expert do?

They specialise in strengthening and repairing foundations. They use a variety of methods to do this, including:

• Mass concrete underpinning: the pouring of concrete under the foundation to support it
• Resin injection underpinning: when resin is injected into soil to stabilise it and strengthen the foundation
• Piling underpinning: when piles are driven into the ground under the foundation to support it

The best method for your home will depend on the specific problem and the condition of your foundation. An underpinning professional will be able to assess your foundation and recommend the best solution for your needs.

Read more: How does underpinning work? and which underpinning method should I use?

Most common issues that require underpinning

The most common problems that require underpinning are:

• Settlement, when the foundation sinks due to the weight of the building or changes in the soil conditions
• Erosion, when the soil around the foundation is washed away, weakening the foundation
• Tree roots that damage foundations
• Poor drainage which creates water logging around the foundation

If you're concerned about any of these issues, it's important to have your foundation inspected by someone who understands underpinning.

How much does it cost to hire an underpinning expert?

Businesses in Australia typically charge between $10,000 and $20,000 for underpinning a house. However, the cost can vary depending on factors such as soil type, footing type and access. Engineering and other miscellaneous costs can sometimes be extra on top of existing costs. 

Read more: How much does underpinning cost?

How to hire a reputable local underpinning expert

Before you contact any underpinning businesses, it's important to make a list of questions to ask them. This will help you decide if they're the right fit for your project.

Key questions include:

• What is the cause of my foundation problems?
• What are the different types of underpinning materials and methods that you use?
• What type of underpinning do you recommend for my project?
• How will you minimise the disruption to my property during the underpinning process?
• What is the estimated cost of the project?
• How long will the project take to complete?
• What are the potential risks involved in the project?
• How can I prevent issues with my foundation in the future?
• What is your warranty policy?

Licensing for underpinning experts

Underpinning is a trade work, so anyone carrying out this work must be licensed by the state or territory government where they are operating.

Licensing requirements vary from state to state, but in general, tradies must have certified training in civil foundations.

DIY underpinning is not recommended, as it is a complex and potentially dangerous process. Prior skills and experience are necessary for safe and effective work.

Benefits of hiring an underpinning expert

Underpinning is a complex and expensive job, so it's important to hire a reputable and experienced contractor. By doing so, you can be sure that the work will be done to an exemplary standard, limiting the likelihood of further foundation problems in the future.

Best of all, underpinning experts have the tools and experience to complete the job quickly and efficiently, saving you time and money in the short term.

Getting quotes from underpinning experts

Once you have shortlisted a few potential underpinning companies, be sure to get quotes from each of them before making a decision. This will help you to get the best possible price for the job and ensure that you are getting the best possible value for your money.

*Costs and prices in this article are indicative and should only be used as a guide. They also vary locally and are subject to market forces.