Whether you’re looking after residential properties in Richmond or a heritage property in Hackney, structural damage is a constant and looming threat for much of London’s building stock. No matter how modern your property is, any building is at risk of structural defects related to its construction or its surroundings.
In this blog, we’ll cover what structural problems are common in London, what you can do to spot structural issues early, and what Timberwise can do to help remediate these concerns.
Why Are Structural Problems Common in London?
There are several reasons why structural problems are common in London. Here are a few of the more likely causes of structural problems in your London property.
Clay Soil Movement
London’s soil (especially in boroughs north of the Thames) is predominantly clay-based. This soil is malleable and prone to movement if not properly compacted prior to erecting a building. If a structure is built on unstable ground, it is more likely to generate issues such as subsidence further down the line. Our recent blog on London Clay and Flooding delves a little deeper into this concern.
Ageing Victorian & Edwardian Stock
In boroughs such as Kensington, Westminster and Chelsea, a lot of building stock is composed of pre-1900 constructions. Many of these buildings were not built to withstand the same concerns as more modern buildings, and this makes them prone to developing defects.
Many of these buildings do not incorporate modern remedial solutions due to heritage and conservation concerns. This also means they can only be remediated with methods and materials used in the time of their construction. Many of the materials are less sturdy than modern construction materials, and so recurrence of faults are likely in some serious cases.
Urban Vibration (rail/tube traffic)
The running and expansion of London’s Underground and overground travel network increases the amount of urban vibration within the ground. These vibrations resonate within masonry and concrete, and over time can create hairline cracks that can progressively widen and reduce the structural integrity of a building or its foundations.
Thames Proximity & Water Table Impact
Boroughs bordering the Thames are especially prone to the risks of flooding. High river water levels and reduced soil drainage can allow water to remain on or near the surface for longer, increasing hydrostatic pressure behind below-ground structures like basements or cellars. This pressure raises the risk of defects forming, allowing water a pathway to ingress into a building and cause further structural cracking.
What Are the Early Warning Signs of Structural Damage?
When inspecting your property, there are some signs you can look out for to assess whether your property has some form of structural damage:
- Step cracking in brickwork, where cracks form in the mortar joints between brickwork rather than through the individual bricks themselves.
- Bowing walls, where pressure from above or the opposite side of a wall causes the wall to bulge inward.
- Internal plaster cracking, which may indicate damp penetration or structural movement in the masonry behind the plaster.
- Sticking doors and windows, where their timber frames have become compressed from above or the side, similar to bowing walls.
- Uneven floors, especially in ground-floor rooms where lateral damp penetration or flooding may have caused the floorboards to bow or weaken over time.
How do I Tell the Difference Between Structural Movement and Cosmetic Cracks?
There are several ways to tell the difference between structural movement and cosmetic cracking.
The Size of the Cracks
Many times, a cosmetic crack will be noticeably smaller than a structural crack. A cosmetic crack is often a superficial hairline crack (less than 2mm in depth, or thinner than a 10p coin). Conversely, structural movement often results in much deeper fissures (often 3-5mm or larger) than cosmetic cracking.
The Direction of a Crack
Cosmetic cracking often (but not always) follows a vertical pattern. This is usually where new plaster has dried too quickly, or where the join between two sections of plasterboard has not been correctly taped prior to plastering. These cracks may also spread outward from an area of increased vibration, such as a doorway or window frame.
Structural cracking in plaster will often mirror a similar defect in masonry. A stepped look, where a crack has formed in the mortar joints between individual bricks, may indicate an area of subsidence. Similarly, an area of horizontal cracking may indicate an area of moisture ingress or an issue with the foundation.
Building Movement
Cosmetic cracking often appears in areas of direct or adjacent impact or short-term environmental changes. Structural cracking is often the result of long-term foundation movement or structural issues causing strain in other areas of a building.
Other Associated Symptoms
For cosmetic cracks, the crack itself is often the most obvious symptom. This can sometimes be accompanied by a damp patch or blemishes on the wall near a crack, which may have contributed to a crack forming or worsening.
Structural Movement often carries with it more severe visible issues. Walls that are visibly bowing or doors becoming jammed in their frames can imply areas where the load-bearing structure of a wall has failed and is exerting pressure on the structures beneath it.
When do I Book a Commercial Structural Survey in London?
You should book a structural survey at any time if you suspect your property is at risk of future damage from a structural defect. Having a specialist surveyor attend your property will allow them to correctly diagnose a property defect and provide remedial plans to restore the property’s structural integrity.
What is the Cost of Delaying Structural Repairs in Commercial Property?
Often, it is more cost effective to remediate structural damage the earlier it is caught. Repairing a defect as soon as possible will will restore integrity to the property, and significantly reduce the likelihood of further damage developing.
Not repairing a defect when found can cause implications for your buildings insurance. Having knowledge of a defect and ignoring necessary remedial work can render your policy void, leading to the loss of capitol if your property develops future issues.
Ignoring remedial concerns also carries a risk to tenants. Whether a commercial or residential property, keeping a property in a state of disrepair can place its occupants at risk of injury or wider health concerns. Last year’s passing of Awaab’s Law carries with it implications for ensuring the safety of residential tenants, and any defects should be remedied within a short timescale and with as little disruption as possible.
Finally, ignorance of structural problems can expose property owners to compliance concerns. Legislation such as the Buildings Safety Act (2022) introduced stricter responsibilities for building designers, contractors and owners. Non-compliance with this and other legislation could lead to enforcement notices, fines, or the inability to sell a property until remedial action is taken.
How Does Timberwise Support its London Commercial Clients?
Timberwise’s team of surveyors are backed by over 50 years of industry knowledge to diagnose and treat structural issues from cracking to subsidence in both heritage and modern constructions. You can book a structural survey at any time if you suspect your property is damaged or at risk of future damage from a structural defect.
Once surveyed, our team of specialist technicians are available to conduct remedial work to repair any structural damage to your property. This includes repairs to concrete, lintels, timber structures, and masonry. Our work is guaranteed for up to 20 years, and are insurance-backed to ensure correct remediation is provided for your unique property situation. Our work is also backed by the Property Care Association’s PCA Promise.
FAQs
Are Cracks in Office Buildings Always Structural?
Not always. Surface cracking can occur for several reasons, including vibrations, impact damage, or structural shifts. Renovation work within a building can also cause non-structural cracking to occur.
Who is Responsible for Structural Repairs in a Leased Commercial Property?
The landlord is responsible for all structural repairs within a leased commercial property, such as the roof, foundation, and exterior walls. They may look to reclaim some of these costs through a building maintenance fee, which should be agreed prior to the start of any tenancy.
Depending on the lease agreement, a tenant may be liable for damage caused through negligence or for interior / non-structural maintenance. If the tenant has signed a Full Repairing and Insuring (FRI) lease, this would place responsibility for all costs for repairs, maintenance and building insurance on the tenant.
How Long Does a Structural Survey Take?
The time to complete a structural survey depends on the severity of damage and the size of the property. A structural survey can typically be completed within a few hours for many residential or smaller commercial properties.
For larger properties, a thorough survey may require a full day to ensure any defects are identified. A finished survey document with remedial recommendations is usually supplied within 10 working days of a surveyor attending a property.
