Cracks in Walls: Is Subsidence to Blame?

When you find cracks in walls, floors or ceilings, it can be alarming for any property owner, whether commercial or domestic. But while they can be worrying, not all cracks in and around your home will signal subsidence. In this article, we’ll be explaining what subsidence is, what subsidence cracks look like and when not to worry. We will also advise you on what to do next should the cracks around your property be synonymous with subsidence.

What is subsidence?

Subsidence refers to the slow sinking or downward movement of building foundations as a result of unstable soil below. When the ground beneath begins to shift, it will often bring the structure that sits on top down with it. It will almost always result in an even drop, therefore compromising the integrity of the building. 

Some of the main causes of subsidence include clay or sandy soil, tree roots extracting moisture from the ground, leaking drains and poorly compacted ground. One of the most common signs of subsidence is the appearance of cracks in walls, floors, and ceilings, which brings us to our next point: identifying subsidence cracks.

How to identify cracks caused by subsidence

It’s important to note here that not all cracks you find in and around the home are indicative of subsidence. However, if it’s something you’re particularly concerned about, then there are some ways of identifying subsidence cracks, separating them from harmless hairline cracks, for instance. Here are some signs that the cracks you’re looking at could be a result of subsidence and ground movement:

• Cracks running in a diagonal line or zig-zag pattern
• Cracks that are more than 3mm wide
• Cracks appearing around doors and windows
• Cracks that rapidly worsen or quickly develop
• The same crack is visible both inside and outdoors

When do cracks not indicate subsidence?

As we’ve already touched upon, not all cracks in and around the home are indicative of subsidence. In fact, there are some cracks that are entirely harmless and that can be easily fixed by a competent contractor. Some of the most common situations where cracks do not indicate subsidence are as follows:

Cracks that don’t signal subsidence

• Hairline cracks – these can come about as a result of new plaster drying out or general shrinkage. They can also occur where plaster hasn’t been joined properly between walls and ceilings or from wall to wall. They’re usually less than 1mm wide
• Thermal expansion and contraction – temperature changes can cause building materials to expand and contract, which can lead to seasonal cracks. Seasonal racks can appear in walls and ceilings, but also around doors and windows. They’re typically less than 1mm wide
• Settlement cracks – common in new-build homes or in house extensions and new plaster. If the cracks are vertical and shallow, and occur within the first year or two, then it’s not a cause for concern. However, you can opt to have a subsidence survey carried out by Geobear if you want to be absolutely certain
• Poor workmanship or low-quality materials used – cracks can occur as a result of improper plaster application, substandard paint or filler being used or poor drywall taping. These are cosmetic issues and can be easily rectified
• Vibration or impact – vibrations from traffic or construction work nearby can cause cracks in the home. Even slamming doors can result in hairline cracks. Cracks caused by these things are superficial and so shouldn’t be anything to worry about
• Natural ageing of materials – buildings will settle and materials degrade over time, even if they’re hundreds of years old. Cracks in older properties can be down to a degradation of materials, particularly in walls and ceilings. 
• Decorative features or movement joints – some houses will include intentional joints that are designed to allow for movement. If cracks appear here, this is expected and not indicative of a structural problem

What should I do if I find subsidence cracks?

If you think that you have identified subsidence cracks, then don’t panic. There are multiple options available to you that will ensure the problem is fixed quickly and efficiently. If you have found subsidence cracks in and around your home, here’s what to do next:

Monitor the cracks closely

Take photos and measurements of the cracks to track their progression. You can pass this information to a subsidence surveyor, such as the team we have here at Geobear. We will be able to provide you with a subsidence report, along with detailed expert guidance on the next steps to take in order to prevent the issue from worsening and to resolve the issue as soon as possible.

Contact your house insurer

It’s important that you have the funds lined up to be able to pay for the underpinning work as soon as a firm becomes available. This part of the process needs to be done quickly and properly so as to prevent the subsidence from worsening. It’s paramount that remedial work is carried out as soon as possible to protect the integrity of the structure. 

Look to Geobear

Geobear offers a non-disruptive geopolymer resin technology that’s an innovative method of underpinning. Unlike traditional underpinning services, the geopolymer resin injection method is completely mess-free and effective, with long-lasting results regardless of the size or complexity of the situation at hand. We will inject the affected ground with geopolymer resin. This resin will work its way through the gaps and voids under the foundations, hardening and expanding as it goes. 

This aids in soil compaction and ground stabilisation, restoring strength and stability to the soil and, therefore, to the foundations themselves. The structural integrity of your home will be stabilised quickly and efficiently with our geopolymer resin injection underpinning method. In addition, you won’t have to move out while work is being carried out. Once our work has been completed, you’ll never know that any underpinning ever occurred. 

Geobear provides expert underpinning services nationwide, offering swift and efficient solutions for properties affected by subsidence. Using innovative resin injection technology, we restore structural stability with minimal disruption or mess – a cleaner, less invasive alternative to conventional underpinning. If you’d like to learn more about our approach or schedule a survey with one of our experienced specialists, don’t hesitate to contact us. We’re here to support you.