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Jammed Doors & Sticking Windows

A sign of subsidence

What does a jammed door or a sticking window mean?

Have you noticed jammed doors and sticking windows in your home? These can often be the first sign of structural damage due to movement of foundation ground and soils under the house.

Signs to look for include misalignment or jamming, doors or windows scraping against the frames, or getting stuck. You should investigate the causes of this immediately, as the risk of doing nothing can be more costly down the track.

Understanding Jammed Doors and Sticking Windows: Subsidence Causes and Factors

The issue of subsidence, especially in the context of jammed doors and sticking windows, stems from a multitude of causes and contributing factors. All of these share a common thread—a shift in the ground, resulting in soil movement.
Moreover, the impact varies depending on the type of ground involved. When the ground undergoes changes, building subsidence becomes a prevalent concern.
In such cases, foundations or footings lose their full support and begin to sink due to the weakened ground.

Expansive Soils

A contributing factor is irregular soil behaviour. For example, soils containing reactive clay can expand or contract throughout the year. Rainy seasons will lead to soil expansion from moisture, while contraction occurs in the warm, dry conditions of hotter months. 

These fluctuations could be regular, or the soil may expand and contract unevenly. This causes stress to the foundations of your home, which could lead to internal and/or external wall cracks. This will be of particular concern as more parts of the country experience extreme weather events year on year.

Tree Roots

Neighbouring trees and shrubs absorb water using their roots causing movement in the soil as it soaks up moisture in the ground.

Poor Drainage

One major contributor to jammed doors and sticking windows is issues with drainage. Pipes left unconnected, broken drains and other leakages can mean water drains into the soil under your home. This erodes the soil over time, leading to ground instability. 

The soil under your home could also suffer from aeration, or voids could form. This eventually leads to ground instability, which causes wall cracks.

House Extensions

Jammed doors and sticking windows can appear when the weight of your home increases beyond the foundation’s capacity. Wall extensions or other extra loads increase the weight of the house, as well as increasing the force exerted on the foundation and the soil it sits on.

As with soil expansion, uneven direction or distribution of this force can put stress on the structure. Wall cracks in this case might be the start of more serious issues.

Extreme or Seasonal Weather

Natural disasters such as flooding, drought and earthquakes affect soil moisture levels in particular clay resulting in excessive foundation movement.

Renovation or Construction

Vibration caused by nearby construction activity such as drilling or piling, or heavy road traffic causes soil particles to shift and settle, resulting in ground subsidence.

Expanding Materials

Expanding materials can also cause jammed doors and sticking windows.  Some clay bricks expand as they age, increasing up to several millimetres per year in some cases. Concrete is another material that can contract or shift over time. 

Mainmark Specialises in Re-levelling Homes

It is important to note that jammed doors and windows are a symptom. If you’re worried, call Mainmark to carry out an assessment.

We can improve the ground beneath your house or carry out re-levelling to mitigate further damage.

Mainmark specialises in re-levelling buildings that have experienced structural issues. We developed the Teretek and JOG technologies, which are versatile and suitable for re-levelling both simple and complex structures.

JOG is a non-invasive method of injecting cementitious grout beneath your house. This results in a stabilised and improved foundation.

Teretek uses a method of injecting polyurethane resin beneath your house. As the resin expands, it gently lifts the structure. This is also a non-invasive and cost-effective solution.


Mainmark’s Level Correction Methods Are:


Our technologies have fast curing times and treated areas can be used immediately or without the delays compared to traditional repair methods.

Environmentally Inert

Our technologies use an inert material that is non-toxic and does not leach into the environment or affect the treated area.


Our solutions are of surgical nature compared to traditional methods.


Compared to traditional methods, our solutions are more cost-effective.

Get a quote

Arrange a site assessment in 3 simple steps:

Step 1

Submit your enquiry using our online form. Include a brief message about the type of foundation issues you are experiencing.

Step 2

Our friendly customer service team will be in touch to schedule a site assessment that suits you.

Step 3

One of the Mainmark experts will visit your home or property, assess the damage, and ascertain the likely cause. They will establish the approach needed, creating a plan specific to the needs of your building and provide you with a detailed quote.

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© 2024 The Mainmark group of companies. ‘Mainmark®’, ‘Terefil®’, ‘Terefirm®’ and ‘Teretek®’ are trademarks of the Mainmark group of companies.

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