Reactiive Soil
Table of Contents​
Buildfix team ready for foundation repair and subsidence assessment onsite.

#1 Structural Repair Top-Rated in Australia

We’re happy to check your home for FREE.

What is reactive clay soil? What damage will it do to my home?

Reactive clay soil is a dense material that changes in volume when it absorbs and releases moisture. This absorption and release occurs as seasons change throughout the year. When it’s warm and dry, reactive clay soil releases moisture and contracts. In cooler, wetter periods, reactive clay soil takes on moisture and expands.It’s this contraction and expansion of the ground that leads to structural damage of your home. The damage begins in your home’s foundations and eventually travels throughout the house.Concerned about the stability of your home’s foundations? Read on to learn more about the damage reactive clay soil can do to your home.

Subsidence

Subsidence is the sinking of your home due to a downward shifting of the ground. This sinking occurs when reactive clay contracts as a result of hot, dry weather. Heat will also leave any trees and vegetation around your home particularly thirsty, drawing more water out of the ground and causing further subsidence.If various areas underneath your home subside at different rates, an immense amount of pressure will be placed upon your home’s foundations. Structural damage begins here and leads to…..

Wall Cracks

Wall cracks occur, especially when your house foundations are sitting on ground that is unstable, shifting and as a result, uneven. This unevenness is technically known as differential settlement. The physical stress from differential settlement damages your foundations and eventually manifests itself as cracks, in both your inner and outer walls.Wall cracks are a powerful indicator your home has been built on reactive clay. They’re one of the primary knock-on results of subsidence caused by contracting clay soils.

Sinking concrete and moving house piers

Reactive clay soils can cause concrete slabs or floors to rise or sink throughout the year. If your floors happen to sink while it’s hot and dry, it’s likely your concrete is sitting on reactive clay soil. Cracking may occur due to differential settlement.If your home happens to be built upon house piers, they may move up and down. The piers may even move sideways depending on moisture levels and if the load of your home sits evenly upon the piers. If you’re living in a home on piers, bouncy floorboards, a dip in your floors as you walk and movement of children’s toys on the floor indicate you’re on reactive clay.

Sunken Concrete

Minimising the effects of reactive clay soil

Left untreated, reactive clay soil is a powerful destabilising force on residential structures. It can do immense damage to your home’s foundations, its walls and even your roof.A sure-fire way of stabilising reactive clay soil and halting movement is our proprietary geopolymer resin, GeoPoly™. Once injected into the ground, it sets to compact aerated, damaged soil. It becomes rock solid.If you’re concerned your home has been built on reactive clay soils and are interested in GeoPoly™ as a ground stabilising solution, we’d love to tell you more.Just give us a call on 1300 854 115 or book a FREE inspection today.

Underpinning_feature

Help & Advice

A resource collection of articles, tips and advice

Brick wall with jagged cracks showing subsidence and need for foundation repair.
Wall cracks are common in Australian homes, but not all mean something's wrong. Some are harmless signs of natural...
Jagged ceiling and wall crack indicating subsidence and structural foundation damage.
Every home experiences settlement to some extent. But differential movement occurs when sections of a structure settle u...
Modern kitchen showing foundation repair after subsidence with concealed HelicalBar reinforcements.
Planning a home renovation is exciting. Whether you’re dreaming of a sleek new kitchen, a luxurious bathroom...
Water ingress causing rising damp on concrete slab near sliding door entry.
If you’re planning a renovation, self-levelling compound might seem like the perfect fix for uneven floors...
Scuffed baseboard with chipped paint indicating wall cracks and foundation movement.
A sloping floor is easy to dismiss—until it gets worse. What starts as a slight tilt can turn into misaligned walls, sti...
Close-up of brick wall seam highlighting mortar cracks and foundation repair needs.
A damp proof course (DPC) is your home’s first line of defense against rising damp, stopping moisture from creeping up t...
Water overshoots gutter, risking foundation subsidence and rising damp near patio.
Poor drainage around your home leads to water pooling, soil erosion, and foundation movement. Signs include mould,...
Large foundation wall crack indicating structural movement and potential subsidence issues.
Reactive clay soil is a significant concern for Australian homeowners, capable of causing major structural damage if pre...
Crawl space foundation repair with concrete piers, timber beams, and drainage pipes.
Traditional restumping is an invasive process to replace deteriorated sinking stumps in older homes. It can restore stab...
Hand peels wallpaper to reveal rising damp caused by subsidence Red cricket ball indicates possible foundation movement near overflowing gutter Man inspects under house for structural damage and wall cracks with flashlight.
Before buying a home, pay careful attention to the cosmetic touch-ups....
Example of Subsidence
You don't need to be a geological expert or structural engineer to understand what subsidence is...
guttering_feature_image
Guttering is designed to direct water away from your home and its foundations...