Skip to content

Underpinning Brisbane

Underpinning Brisbane

Having troubles with your foundation? Walls cracking, windows jamming? Your foundations may need repair before it gets worse.

Are you looking for reliable underpinning contractors? Brisbane Underpinning Group is dedicated to underpinning foundations of homes right across Brisbane. We have experience with foundation repairs in reactive soils within Brisbane suburbs. We give expert attention to detail releveling to ensure the structural integrity and beauty is restored to your home.

Due to the reactive soils across Brisbane, many properties are more likely to experience some form of settlement in their foundations. There is a need for strengthening the foundations to help stabilise them. Brisbane Underpinning Group can repair the foundations to make your home safe and secure. This allows you to finally complete the cosmetic repairs that last. We pride ourselves in providing the best underpinning services Brisbane has on offer. We use tailored solutions to provide the best outcome for your home.

Read more to find out why you can be another happy client! 

What causes foundation problems?

There are several reasons why foundation repairs are necessary for maintaining the stability of your home. Here are some of the reasons why we’re house underpinning Brisbane:

Cracking in concrete slab in Coorparoo Brisbane caused by faulty foundations

Faults in the original foundation

Due to poor ground preparation as the house was being built, which is one of the construction defects.
non compacted soil is a reason why Brisbane Underpinning Group have been Underpinning Brisbane homes

Reactive soils

Soils may experience subsidence (which is a shrinkage that occurs due to a decrease in moisture content) or heaving (which is the swelling of the soil due to an increase in moisture content).
Excavations nearby footings can cause foundations problems in Brisbane

Nearby excavations

May destabilize the soil supporting the foundation.
Photo shows flooding in Brisbane can cause foundation issues which then require underpinning

Natural disasters

Such as an earthquake or floods which may weaken or moved the existing foundation.
Construction project in Brisbane construction can add extra weight to a building causing foundation issues needing underpinning

Adding weight to the existing building

By constructing a second story to the property, increasing the weight bearing on the existing footings.
A broken water pipe can cause foundation issues that will require underpinning Brisbane homes

Water leaks in the foundation

Which soak and wash away the surrounding soils resulting in a shift or drop in the foundation.
Dry soil which can cause foundation problems in Brisbane (1)

Poorly compacted soils

It usually occurs when a house is built on poorly compacted backfills. As the soil absorbs water, it pushes against the foundation which weakens it.
image of soil in Brisbane that is being dug for underpinning works

Slope failure

which is the movement of the earth downhill. It may be slow movement over the years, known as creep, which can be corrected using underpinning methods. However, the methods tend to be site specific, requiring assessment by an expert.
It is very important to understand the reason for underpinning the property before determining the ideal method for underpinning a house. Mistaking the causes could worsen the problem, complicating the foundation repair efforts. This may lead to an increase in the cost of underpinning a house. For this reason, when slab jacking Brisbane homes that have suffered house subsidence, we start with an inspection by a qualified engineer and order a geotechnical report.

Why do you need underpinning?

Image is of cracks in a house that need underpinning in Adelaide

Cracking in walls and corners of your home

Screw piles used for underpinning Adelaide houses

Windows no longer opening and closing

Photo shows some of the screw piles used by our underpinning contractors in Adelaide

You’ve noticed your floors are not level

Adelaide Underpinning Group working in Tusmore, Adelaide, underpinning a house

Step cracking has occurred in brickwork

Image is of our team underpinning a house in Unley park Adelaide

Gaps expanding around door frames

Image is of equiptment used by our underpinning Adelaide team

Cracks in wall and floor tiles occuring

What is Underpinning?

Underpinning a house is the process of strengthening the foundations of properties that suffer subsurface destabilization — which are movements in the foundation. House subsidence – the sinking of your home’s foundations – is common for properties built on reactive soils like clay, which are mostly unstable due to changes in moisture content.
Underpinning methods are used to increase the bearing capacity of the foundation to withstand destabilization. At times one side or corner of the house may experience more shrinkage or heaving than other parts, affecting the stability of the structure. If it’s subsidence, this will require house lifting techniques to level the foundation of the house.

House underpinning Brisbane foundations is a process that might involve house lifting, and excavation- removal of the surrounding soils – so that it can be replaced with firmer and stable footings, that will withstand underground destabilization, including changes in moisture content.

The techniques for foundation repair work may differ from one property to another and are very often site specific due to different factors. However, when you engage our reputable underpinning specialists, your house is restored to almost its former state, returning the beauty and stability of your property. 

We are on a mission to provide reliable underpinning services Brisbane residents require for property restorations. We will not rest until your house foundation has been repaired.

Does my house need underpinning?

There are various reasons why your house may need underpinning. These include:

  • Poor drainage which results in water pooling near the foundation
  • Large trees near the foundation suck moisture from the ground
  • Poor construction – if a property is poorly constructed, it can easily become unstable. Underpinning may be a better alternative compared to a total reconstruction of the property.
  • Adding a storey to the house – the foundation will require extra support to bear the additional weight of the storey added.
  • Type of soil your structure is built on – if the soil is reactive, like clay soils, its physical properties are easily affected by elements of weather. Clay expands when wet, and shrinks as it dries. These variations weaken the foundation of a house.

If you’re a homeowner looking for a foundation repair contractor, look no further. We offer reliable underpinning services Brisbane properties require against the reactive soil. Call us today.

Underpin & Hold

The underpins are constructed around the existing foundation. Concrete is poured and left to cure, which holds the structure in position, and stops any further movement.

Underpin & Hold

The underpins are constructed around the existing foundation. Concrete is poured and left to cure, which holds the structure in position, and stops any further movement.

Contact Us

Underpin & Lift

Underpins are constructed around the foundation, followed by house lifting to level the foundation. Concrete is then poured to secure the structure into place

Underpin & Lift

Underpins are constructed around the foundation, followed by house lifting to level the foundation. Concrete is then poured to secure the structure into place

Contact Us

Concrete Underpinning Vs Resin Underpinning

The Concrete underpinning process involves excavating the soils surrounding segments of the foundation in order to increase its strength (known as load-bearing capacity). After excavation, underpins are constructed and concrete is poured and left to cure before it is loaded with the foundation. As the concrete sets and stronger as it dries, it becomes the new foundation. That will increase the depth of the foundation, and the weight of the house is supported from a firm ground, increasing the stability of the property. 


The technique has been around for over a century, and is considered to be more efficient and cost effective compared to resin underpinning method. For this reason, it is more commonly used in house underpinning Brisbane among other places around Australia.

There are two methods of concrete underpinning which are:

  1. Mass underpinning – is whereby underpins are constructed on weaker segments of the foundation, and poured with concrete to strengthen the load-bearing capacity of the foundation. 
  2. Concrete Pilings – the method uses long steel tubes with a screw head drilled into the ground to reach the firm soil layer. The load is transferred to the firm ground which stabilises the foundation.

On the other hand, resin injection underpinning is a simple method that requires no excavation. The technique involves drilling holes into the ground around the foundation and injecting resin under pressure through the holes. It will expand as it dries, binding all the loose soils around the foundation, making it less reactive. However, this method is less preferred because of its associated high risks. For instance, the resin may block any damaged pipes underground, finding its way through any hairline cracks and filling up pipes. Also, if the method fails to stabilize the foundation, traditional methods of underpinning foundations cannot be used. That’s why traditional underpinning is mostly recommended for Brisbane restorations.

What causes foundation problems?

There are various reasons why foundation problems occur. These include:

  • water leaks in the foundation– when there is a leak under the foundation, it may soak and wash away the supporting soil. This will create a drop, shift or crack of the slab and foundation. The larger the leak, the worse it gets.
  • subsidence due to reactive soils– these change with moisture content. Soils that are reactive in this way are often referred to as ‘plastic’. They swell when wet, known as ‘heaving’, and shrink when dry, known as ‘subsidence’. Such changes in physical characteristics affect foundations.
  • Mature trees near the house– problems may arise when roots come into contact with the foundation, or when there is a disturbance of the moisture content of soil surrounding the foundation. The severity of the damage may differ, depending on the species and size of trees, which makes it a bad idea to have trees close to the house.
  • poorly compacted soils– soils that can be compacted have poor drainage properties, which affects foundations of structures. For example, with changing moisture levels clay heaves and contracts, putting stress on the footings of your building. Over time, you will need foundation repair.
Have you noticed any of the following foundation problems?

The cost of underpinning a house is high, depending on the nature of the damage. A faulty foundation worsens over time, and could result in increased underpinning costs, or at worst, a reconstruction project. Here is a better way is to spot the warning signs, and fix them, before it’s too late:

  • Fractures and cracks in walls, floors and foundation – usually gaps will appear in the exterior walls of your house. Cracks will form on the floors and walls may fissure. If your house has a chimney, it usually gets broken. This signals that over time, your foundation may shift resulting in widening gaps, which makes the structure unsafe. However, it’s normal for walls to show tiny hairline cracks. If these cracks get wider than 10 -15mm, that may indicate a problem with your foundation, which can be fixed through underpinning techniques. Oftentimes, wall repairs will be necessary. 
  • Foundation seems to be sinking or settling – If your structure is experiencing house subsidence, it’s better to have it checked. House subsidence is the sinking of the foundation due to weaker soils foundation. Oftentimes you may notice one side of the house becoming lower than others. You can also check for any wet or damp spots that should be dry. Underpinning specialists will use house lifting techniques during foundation repairs to level the house. 
  • Jamming doors and windows – usually windows and doors may jam, and appear to be uneven. For exterior doors, they hang down at the top while the interior doors drag or stick at the top.
  • Gaps around window frames and exterior door frames – you may notice gaps around the window frames and spaces around the exterior doors. You may even notice that the exterior doors no longer latch.
  • Cabinets and counters separating from the wall – fitted kitchen cabinets and countertops may tilt or pull away from the wall. The gap gets wider as the problem worsens. If your walls are not level, the cabinets and countertops follow suit, indicating problems with a foundation.

If you notice some of these unusual signs, always carry further investigation before deciding on underpinning methods to use. Contact Brisbane Underpinning Group to inspect the property and determine whether foundation repair is necessary. 

When underpinning foundations, choose reputable underpinning contractors Brisbane homeowners have hired before. We pride ourselves in offering the best underpinning services Brisbane has on offer. In Pullenvale and Ascot, Balmoral and Hamilton, we continue to use our methods that are site specific, and tailored to bring stability in your property. Call us today for a consultation! 

Request an appoinment