Cavity Wall Tie Replacement Specialists

Many properties across the UK are constructed using cavity walls, which are held together with wall ties. Over time they can fail and need to be replaced. Wall ties can fail for numerous reasons, including the type of tie used, the age of the tie, general deterioration and environmental factors. If you have noticed signs of cracking and structural damage, repairs may be required to prevent further problems at a later date.

Rentokil Property Care have been protecting properties for over 70 years, and can provide advice and solutions for wall tie problems. Our trained surveyors can carry out a wall tie survey to assess the condition of ties, and provide advice and solutions where necessary. If we find any problems with the wall ties we can provide recommendations for repairs - but only if they are required.

Rentokil Property Care are approved installers of Helifix and Cintec structural products and can work closely with structural engineers if needed. If you are worried about the stability of your property, we can provide you with advice and solutions, giving you peace of mind. Typically our wall tie repairs are backed by long term guarantees, so your property is protected for the foreseeable future.

Cavity walls are formed by two layers of masonry with a gap in between and the cavity wall tie is used to hold the inner and outer leafs of masonry in place, tying them together. This provides stability against wind, while the cavity stops penetrating damp reaching the inner leaf and acts as a thermal barrier.

Cavity walls have been around since the Victorian era, however it wasn’t until the 1920’s when they became the standard in the UK. Before then properties were mainly constructed with solid walls, which can suffer from penetrating damp and do not provide as much thermal insulation as cavity walls.

There are various types of wall ties, original ‘fishtail ties’ with split splayed ends were made from mild steel or iron and galvanised wire 'butterfly' ties, both of which are embedded directly into mortar joints. Newer ties tend to be stainless steel which provides better resistance to rust and corrosion. Older wall ties when exposed to moisture or salty air can corrode and expand in the mortar joints, leading to horizontal cracking, lifting of brickwork and the walls bulging outwards.

When the ties corrode the two leaves are no longer connected which can lead to structural movement and eventual collapse. Pressure differences caused by strong winds passing across the wall can cause bricks to be pulled away, once the wall ties have broken.

It is not uncommon for entire developments of homes to have the same problem, as all properties would be built at the same time using the same ties. It is possible for the wrong number or pattern of ties to be inserted when the homes were built. Many properties along the coast may suffer from wall tie problems due to the salty sea air and wind driven rain.

Cavity wall ties were initially made from iron or steel, but when these ties are subjected to damp conditions, they corrode. To prevent this deterioration, wall ties were galvanised with a protective zinc coating, but over time this protective layer will break down and cause the tie to fail. It was not until 1945 that the first British standard wall tie with a defined zinc coating was introduced and this standard was improved in 1981.

Cavity wall ties produced before 1981 have a history of premature failure and every year many homes across the UK suffer from cavity wall tie corrosion as a result of corrosive (black ash) mortars, permeable lime mortars, exposure to wind-driven rain and coastal locations.

When fishtail wall ties corrode, they start to expand in size, forcing the outer leaf to crack along the mortar joint. This exacerbates the issue, allowing more moisture into the cavity, corroding ties further. If Wire Butterfly ties corrode, they tend to snap without expanding, so the first sign of a problem may be bulging in the wall, as the outer leaf moves away from the inner leaf.

Properties built before 1981 could require cavity wall tie replacement with new wall ties. To avoid wall tie failure in modern building construction and reduce the need to replace cavity wall ties in the future, never wall ties are made from stainless steel to prevent corrosion.

Wall tie failure may be hard to spot as the ties are hidden within the mortar and cavity of a wall. That said, if the ties have corroded to the point they are causing structural damage, you may be able to notice this through an inspection of your walls.

Rentokil Property Care Surveyors are equipped with tools which can be used to inspect the condition of ties, firstly by identifying ties with a metal detector, and then using a borescope to inspect the tie.

If you suspect your property could have a problem with cavity wall tie failure or require cavity wall tie replacement, it is essential to seek advice from a specialist surveyor. To accurately determine if cavity wall tie failure is the cause of the problem, we recommend having a cavity wall tie survey carried out on your property.

Our surveyor will inspect your wall ties to check their condition, density of existing ties across the property, and assess if there is any damage to the masonry. They will use diagnostic tools such as a borescope, which is a camera on the end of a tube and metal detectors to inspect the ties.

They will use Building Research Establishment (BRE) Digest 401 to understand the condition of the ties, and establish whether there is an issue and if cavity wall tie replacement will be required.

Once the surveyor has completed their survey, they will provide you with a survey report detailing their findings, with a full assessment of the condition of the property, and any building defects that were noted. If wall tie condition is fine and they do not require replacement, the surveyor will detail this in the survey report.

However, if they have spotted signs of any cracks or defects to masonry and wall tie failure, they will provide you with a quote for cavity wall tie replacements. Typically wall tie replacement work carried out by Rentokil Property Care comes with a 20 year guarantee, giving you long term peace of mind.

The time the surveyor will take to assess the property will depend on the size, and the amount of wall ties in question.

Surveyors will need to drill holes in the mortar and may even need to remove bricks to fully assess ties, which can cause the survey to take longer. A typical property can take between an hour and two hours, but this will vary depending on circumstances.

If our surveyor has identified your property requires cavity wall tie replacement, you will receive details of a treatment plan specifically designed for your property.

Our specialist technicians will treat the problem by locating and replacing corroded wall ties. Our cavity wall tie replacement service for failed wall ties involves:

• Locating the current wall tie by using a metal detector, before marking their position.
• Drill holes for new wall ties in appropriate areas of brickwork, using low impact drills to reduce damage to the masonry.
• Install new non-corroding stainless steel wall ties at the correct density and then pull tested to confirm a secure hold. Remedial wall ties are designed explicitly for existing walls. Our surveyor will discuss and recommend the best type of cavity wall ties for your property depending on the type and condition of the masonry.
• In most cases, the corroded wall ties are isolated to prevent further damage but may need to be removed. Old wall ties are removed after the new wall ties have been inserted, otherwise there is a risk of wall instability.Drill holes are covered to match the existing wall appearance and preserve the facade of your property.

Any work required to fix bulging or cracked brickwork will be able to be carried out once the cavity wall ties have been replaced and the wall is secure. To ensure the stability of your property, any remedial treatment to replace cavity wall ties should be conducted by a qualified specialist experienced in cavity wall tie replacement.

Upon completion, the replacement cavity wall ties are covered by our 20-year guarantee, giving you peace of mind that should a problem occur in the future you are covered. Even if you decide to sell your property we will be able to transfer your guarantee to the new owner.

Rentokil Property Care have qualified surveyors working out of our network of branches across the UK, meaning we have an expert local to you. 

Rentokil Property Care are approved installers of Helifix and Cintec structural products and have considerable experience of working with structural engineers across the UK. Our structural cavity wall tie repairs are backed by a 20 year guarantee offering you long term peace of mind.

We are proud members of the Property Care Association (PCA) with a range of CSTDB and CSRT qualified surveyors. When you work with us you can be assured that
you’re getting professional and honest advice, and treatments following the industry best practice.

Our damp proofing, structural repairs and timber treatments are rated ‘Excellent’ with over 1,000 reviews from our customers - showcasing our professionalism.

We are endorsed by Which? Trusted Trader - meaning our customer service and workmanship has passed the rigorous trading standards assessments.

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  Do I need a wall tie survey?

  If you are worried about cracking and bulging of walls on your property, a wall tie survey can be carried out to inspect the condition of the tie within the mortar and cavity, and understand if this is causing any issues. A surveyor can provide you with a detailed survey report, and can answer any questions you may have. A survey can provide you with peace of mind a professional has inspected the issue, and provided you with advice and solutions.

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  How much does it cost to replace cavity wall ties?

  Wall tie replacement costs will depend on the size of a property, the type of building and the extent of the structural damage. For large buildings scaffolding may be required to fully assess all wall ties. You can get in touch with Rentokil Property Care to book a survey which will provide answers around the costs involved for repairs.

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  How urgent is wall tie replacement?

  Wall tie failure can lead to cracking, bulging and can even cause the outer leaf of brickwork to collapse in windy conditions. If you require wall tie replacements you should get in touch with a specialist as soon as you can.

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  What happens if you have cavity wall tie failure?

  Wall tie failure can cause serious structural damage if left, leading to horizontal cracking, walls bowing and bulging and even collapse. As the wall ties rust and corrode mortar and masonry may become loose and fall away, leading to further issues such as damp ingress.