Introduction
Noticing cracks in your home can be unsettling, but don’t panic just yet—cracks aren’t always a sign of serious damage. In this post, we’ll explore the various types of cracks that can appear in your property, what they might mean, and the kinds of repairs that could be required to keep your home safe and sound.
Contents
Types of Cracks and What They Mean
The BRE 251 Digest: A Comprehensive Assessment of House Cracks
The Building Research Establishment (BRE), formerly known as the Building Research Establishment, conducted an in-depth survey of 130 houses affected by subsidence. From this, they created a damage category list that helps homeowners and professionals assess the severity of cracks. Here's a breakdown:
0– Hairline cracks of less than about 0.1 mm which are classed as negligible. No action required.
1– Fine cracks that can be treated easily using normal decoration. Damage generally restricted to internal wall finishes; cracks rarely visible in external brickwork. Typical crack widths up to 1 mm.
2– Cracks easily filled. Recurrent cracks can be masked by suitable linings. Cracks not necessarily visible externally; some external repointing may be required to ensure weather-tightness. Doors and windows may stick slightly and require easing and adjusting. Typical crack widths up to 5 mm.
3– Cracks that require some opening up and can be patched by a mason. Repointing of external brickwork and possibly a small amount of brickwork to be replaced. Doors and windows sticking. Service pipes may fracture. Weather-tightness often impaired. Typical crack widths are 5 to 15 mm, or several of, say, 3 mm.
4– Extensive damage which requires breaking-out and replacing sections of walls, especially over doors and windows. Windows and door frames distorted, floor sloping noticeably. Walls leaning or bulging noticeably, some loss of bearing in beams. Service pipes disrupted. Typical crack widths are 15 to 25 mm, but also depends on number of cracks.
5– Structural damage that requires a major repair job, involving partial or complete rebuilding. Beams lose bearing, walls lean badly and require shoring. Windows broken with distortion. Danger of instability. Typical crack widths are greater than 25 mm, but depends on number of cracks.
Cracks below 5 mm in width can be considered aesthetic only and therefore can be repaired by a painter/decorator. Cracks over 5 mm will generally require a structural repair which in many cases will need to be specified by an engineer. As cracks become very significant, it will be necessary to break out sections of brickwork and possibly rebuild whole portions.
What Causes Cracks in Your House?
Understanding the cause of a crack is crucial to determining the appropriate repair method. Here are some of the most common reasons for cracks in houses:
Subsidence
Subsidence refers to the downward movement of soil beneath a building. The most frequent cause is tree roots extracting water from shrinkable soils like clay. Over time, this can cause the soil to contract and the house to settle unevenly, leading to cracks.
Another cause of subsidence can be broken drains leaking water into the surrounding soil, which weakens it and causes the foundation to shift. Subsidence-related cracks are usually wider at the top of the house and often run diagonally.
Repair Approach:
Trial holes: Assess ground condition, foundation type and depth
CCTV Drainage Survey: Condition check of underground drainage
Tree Removal: Gradually remove the offending tree to prevent sudden soil expansion (heave).
Underpinning: Strengthen the foundation by underpinning the property.
Settlement
Settlement occurs when a newly built structure or an extension to an existing property settles into the soil beneath it. This is typically a one-time occurrence and should cease after the initial settlement phase.
Repair Approach:
Decorative Repairs: For minor cracks, a simple fill and repaint should suffice.
Brickwork Stitching: In some cases, it may be necessary to stitch the brickwork to ensure stability.
Heave
Heave is the opposite of subsidence—it’s the upward movement of soil, often caused when a tree is removed and the soil reabsorbs water that the tree previously drew out. This rehydration causes the soil to expand, potentially pushing up the foundation. Heave-related cracks usually taper as they rise and are wider at the bottom of the structure.
Repair Approach:
Controlled Tree Removal: Remove trees in stages to minimize the risk of heave.
Foundation Stabilization: Additional measures might be needed to stabilise the foundation if the heave is severe.
Thermal Movement
All building materials expand and contract as temperatures fluctuate. Modern construction methods often include movement joints to accommodate this, but older buildings without such joints can develop cracks due to thermal expansion and contraction.
Repair Approach:
Movement Joints: Install movement joints in vulnerable areas to control where cracks may form.
Temperature Control: Implement shading or insulation to reduce temperature extremes.
Seasonal Movement
In regions like the UK, where the climate can vary significantly between seasons, shrinkable soils such as clay can expand and contract with changes in moisture levels. This is especially common in older buildings with shallow foundations.
Repair Approach:
Regular Maintenance: Since these cracks can open and close with the seasons, regular monitoring and maintenance are key.
Decorative Repairs: Often, these cracks can be treated with routine decorating.
Lintel Failure
Lintel failure is caused by lack of, undersized or deterioration of the lintel. For example, many older properties have timber lintels, through lack of maintenance these can be affected by timber decay and rot or where windows are upgraded the lintel is not to cut costs, however in the long run structural issues usually make the whole thing more expensive. Often older buildings also rely on self-supporting brickwork like brick arches, these are affected by other types of movement and may need repairs too.
How to Monitor and Inspect Cracks
When dealing with potential structural issues, it’s important to determine whether the movement causing the cracks is ongoing or has stabilised. Here’s where synchronous and diachronous inspections come into play:
Synchronous Inspection: Provides a snapshot of the property at a specific time, indicating the type and extent of existing cracks.
Diachronous Inspection: Involves multiple inspections over time to track any ongoing movement. This is particularly useful in cases of subsidence where monitoring can show whether further movement is likely.
For serious cases, such as those involving subsidence, structural surveys and professional monitoring might be required. This typically involves repeated visits to assess ongoing movement and determine when it’s safe to carry out repairs.
Final Thoughts
Cracks in your house can range from minor cosmetic issues to serious structural concerns. Understanding the type and cause of the crack is the first step in deciding how to address it. Whether it’s subsidence, settlement, heave, or another cause, early detection and appropriate repairs can prevent further damage and protect the value of your home.
If you’re unsure about the severity of a crack or the best course of action, don’t hesitate to consult with a Chartered Building Surveyor or Structural Engineer.
Don't Let Cracks Compromise Your Properties Safety!
If you've noticed cracks in your property or are concerned about structural issues, don't wait until the problem worsens. Contact AMS SURVEYS today for a comprehensive assessment. Our expert team will provide you with a detailed analysis and guide you through the best course of action to ensure your home or property remains safe and sound.
Contact Us Now for a Free Consultation! Call us at 0151 314 6650 or visit our website at www.amssurveys.co.uk to schedule your survey.
Protect Your Investment—Act Now!
FAQs About House Cracks and Structural Surveys by AMS Surveys
1. What types of cracks should I be concerned about?
Cracks wider than 5 mm, especially those that are diagonal or vertical, could indicate serious structural issues like subsidence or heave. If the cracks are over 15 mm, you should consult a professional immediately.
2. How can I tell if a crack is getting worse?
Monitoring cracks over time is essential. If you notice the crack widening, lengthening, or new cracks forming, it’s a sign that the underlying issue might be worsening. A diachronous inspection (multiple inspections over time) can help track changes.
3. What is subsidence, and how does it cause cracks?
Subsidence is the downward movement of the ground beneath a building, often caused by tree roots extracting water from clay soil, broken drains, or previous mining activity. This movement can cause the foundation to shift, leading to cracks, particularly diagonal ones.
4. What services do AMS SURVEYS offer for cracks in my house?
AMS SURVEYS provides a range of services, including structural inspection surveys, crack monitoring, and detailed assessments to determine the cause and severity of cracks. We also offer recommendations for repairs and can coordinate with trusted contractors.
5. How much does a structural survey cost?
The cost of a structural survey can vary based on the size of the property and the extent of the issues. Contact us for a tailored quote based on your specific needs.
6. What is the difference between a synchronous and a diachronous inspection?
A synchronous inspection provides a one-time snapshot of the current state of your property, while a diachronous inspection involves multiple inspections over time to monitor any ongoing movement or changes.
7. How long does a structural survey take?
A typical structural survey can take anywhere from a few hours to a full day, depending on the size and complexity of the property. After the survey, it usually takes a few days to receive a detailed report.
8. Can I fix cracks myself, or do I need a professional?
Minor cracks (less than 5 mm) can often be repaired with simple DIY methods like filling and repainting. However, cracks larger than 5 mm, especially those related to structural issues, should be assessed and repaired by professionals.
9. What should I do if I suspect my house is subsiding?
If you suspect subsidence, it’s crucial to act quickly. Contact AMS SURVEYS to arrange a professional inspection. We can assess the situation and provide guidance on the next steps, including necessary repairs.
10. Why choose AMS SURVEYS?
AMS SURVEYS has years of experience in assessing and diagnosing structural issues. We provide detailed, accurate reports and work closely with homeowners to ensure the safety and integrity of their properties. Our team is dedicated to delivering top-quality service with a focus on customer satisfaction.
Don't Let Cracks Compromise Your Properties Safety!
If you've noticed cracks in your property or are concerned about structural issues, don't wait until the problem worsens. Contact AMS SURVEYS today for a comprehensive assessment. Our expert team will provide you with a detailed analysis and guide you through the best course of action to ensure your home or property remains safe and sound.
Contact Us Now for a Free Consultation! Call us at 0151 314 6650 or visit our website at www.amssurveys.co.uk to schedule your survey.
Protect Your Investment—Act Now!
Comments