Repairs to Victorian Period Property with Bowing Masonry
This tall brick-built Victorian-type townhouse in Southwark, South-East London, has 3 floors plus a basement.
The very large rear brick wall of the property was visibly bulging outwards and the brick arches above the windows were dropping and cracking. The property owners had contacted AWT before the problem had become too severe, so there was no significant cracking and failing of the main brickwork. The front bay window was also suffering from some cracking and distortion.
The Structural Problem
Bulging Brickwork
Cracked Cill
Bowing Brickwork
Bulging Masonry
In common with many properties of this period, ageing and inadequate restraining of the brickwork had allowed the masonry to bulge outwards. Without structural repairs, the bulging of the masonry would continue and accelerate, allowing the brickwork arches to drop and fail and the main elevational brickwork to become unstable and collapse.
Rebuilding such a large area would be very costly and hugely disruptive to the residents. AWT was asked to provide a cost-effective, long-term structural repair.
Cracked Cill
Failing Masonry
Failing Brickwork
The brick window arches were also dropping and cracking, another progressive structural defect that required a long-term solution.
The Structural Repair Solution
Before Repairs
As indicated with red lines and green stars, stainless steel corded joint reinforcement and grouted helical bars were installed within the masonry using precision diamond drilling techniques. This forms a deep masonry beam that adds tensile strength to the structure. It also redistributes the upper-storey loads and restrains any diagonal cracking and bulging tendencies.
As indicated with green lines, grouted helical stainless steel pins were used to realign and reinforce the brick arches.
As indicated with yellow stars, resin-bonded stainless steel lateral restraints were used to restrain the brickwork from bulging outwards.
The cracked window cill at the front of the property was repaired with an anti-carbonation cosmetic-grade mortar. Areas of damaged or disturbed mortar were made good with colour-matched mortar.
No Rebuilding, No Visible Fixings
Bulging Masonry
Repaired Bowing Brickwork
Repaired Bulging Wall
AWT’s specialist structural repair techniques allowed masonry to be realigned and strengthened without rebuilding work or any visible fixings. This preserved the property’s period features and saved the homeowners time, money and inconvenience.
Cracked Cill
Repaired Cill
After Cill Repairs
Failing Masonry
Repaired Masonry
Repaired Window Arches
Action Wall Ties are specialists in structural repairs, including bulging and bowing masonry. AWT works on large and small projects with homeowners, architects, project managers, London borough councils and local authorities.
AWT are available in Kent, London, Essex, Surrey and Sussex. To arrange a survey or to discuss project details, please use our contact form, email us or call us on 01227 721 255.
Structural Repairs to Bowing Gable Wall Prior to Loft Conversion
The AWT team were called in to inspect this Victorian / Edwardian end-of-terrace home in London SE15. The owners planned to add a loft extension but their plans were on hold due to the significant, visible outward bulging of the large gable end wall.
Before Repairs to Bulging End Wall
During Repairs to Bulging End Wall
After Repairs to Bulging End Wall
The Structural Problem
A survey team visited this property in the London borough of Southwark to identify the root cause of the bulging of the large, solid brick flank/gable wall. The survey team reported that due to ageing, ineffective and inadequate restraining of the brickwork the entire gable wall was de-bonding and disconnecting from the rest of the masonry.
This large gable wall would continue to pull away and without structural repairs, eventually collapse. Traditional building methods would have required the partial deconstruction and rebuilding of the gable wall. Rebuilding work is slow, expensive and disruptive and it would not solve the root cause of the problem which is the inadequate restraining of the gable end wall.
The loft conversion project could not proceed until the gable end wall had been stabilised. The owners were looking for a fast, cost-effective, long-term solution to the structural defect in the gable end wall of their property that would allow the loft conversion to proceed.
The Structural Repair Solution
The bowing gable brickwork required restraining before loft conversion work could begin. AWT designed a complete structural repair program that would realign the brickwork and also add tensile strength to the structure. Their specialist tools and fixings allowed the restoration of the gable end wall’s strength and integrity without the need for visible fixings or costly rebuilding work.
AWT utilised several specialist techniques:
Bed joint reinforcement beaming
Grout tie injection
Lateral restraints
The structural repairs were carefully targeted to reinstate the uniformity of the wall and restrain the masonry from bulging outwards. The formation of continuous beams within the brickwork redistributed the upper-storey loads and restrained diagonal cracking and bulging.
A specialist drilling rig, designed by AWT, was used to drill through the brickwork at a shallow angle to maximise the number of bricks connected by each helical, grout bonded fixing. The internal timber beams were reconnected to the masonry using resin-bonded stainless steel fixings.
Cracked and disturbed areas of mortar were replaced with new mortar that was matched for colour, texture and pointing style.
AWT’s specialist gable end wall repairs provided a long-term solution for this bulging gable wall masonry. The work was finished swiftly and with minimum inconvenience to the residents. The hidden fixings used by AWT also preserved the appearance of the old yellow stock brickwork.
Action Wall Ties are structural repair experts. We have specialist skills in the reinforcement and repair of large areas of bulging or bowing masonry, such as gable end walls. AWT work along with property owners, architects, project managers and local authorities on large and small projects.
AWT are available in Kent, London, Essex, Surrey and Sussex. To arrange a survey or to discuss project details, please use our contact form, email us or call us on 01227 721 255.
Kingsway Square in Battersea, South West London is a Grade II listed building, formerly known as Mountfield Mansions, it formed part of Westminster College. Designed by E. W. Mountford in the late 1800s, it is an impressive building packed with architectural details.
The Victorian era Dutch gables, composed of red brick and ornate stonework were structurally unsafe and at risk of collapse. A sympathetic structural repair solution was required that could restore structural integrity without compromising the beauty of the facade.
The Structural Problem
Inspection of the Dutch gables walls that feature in this grade 2 listed building revealed that they had failed structurally. The masonry could be manually rocked and was leaning and at risk of collapse. Cracks were evident in the gable masonry and stonework. The masonry of the gable walls required urgent realignment and strengthening.
Traditional building methods would require deconstruction and rebuilding each gable wall. This would obviously have entailed substantial inconvenience to the residents as well as additional costs for internal redecoration. A cost-effective, long-term structural repair was required.
Due to internal concerns, one of the residents also required a tailor-made solution that used exterior steel fixings.
As with many buildings that AWT is called in to repair, there was evidence of previous structural repairs. Patress/anchor plates were visible on the brickwork but they had failed to address the root causes of the unstable gable masonry.
The Structural Repair Solution
Dutch Gable Repair Plan
Custom Drilling Rig
Precision Drilling
Lateral Restraints
AWT provided a bespoke structural repair solution to reinforce the gable walls. AWT’s unique skill set and proven experience were invaluable on such a delicate project.
The consulting structural engineers recommended the most appropriate remedial solution would be to install Cintec anchors vertically through the top of the stone and extending at least as far below the rafter line as the stonework extends above it.
A custom diamond drilling rig was required to allow precision drilling through over 3m of stone and brickwork at the apex of the gables. The Cintec sock anchors were then installed.
Cintech sock anchors consist of a stainless steel rod in a mesh sleeve. The anchor is installed deep into the masonry by the use of precision drilling techniques. The sleeve is then filled with a specially designed cementitious grout. This provides a mechanical and chemical bond between the masonry and the anchor that restores structural strength. The small diameter drill holes required for Cintech sock anchors are filled with color-matched mortar to provide a virtually invisible repair.
In contrast to long, drawn-out rebuilding work, Cintech sock anchors provide a highly efficient repair method. This technology also removes the need to use visible fixings such as pattress/anchor plates.
Four lateral restraints were also installed on each side of the gables to restore structural integrity and restrain the masonry. These stainless steel lateral restraints screw directly into the timber rafters and are resin bonded to the masonry to provide a long-lasting structural reinforcement of the gable walls.
Special Request Alternative Repair Solution
For the resident that requested exterior steel fixings a bespoke, Y-shaped frame was fabricated. This was fitted out of sight, to the rear of the gable masonry, ensuring it did not interfere with the lightning conductors on the gable.
Unstable Victorian Gable Wall
Bespoke Gable Reinforcement
Gable Reinforcement Bracket
The AWT team carefully cut away the protruding moulding at the rear of the gable to provide a flat surface. The bracket was then fixed in place with stainless steel resin bonded fixings. The finished repair provided a long-term structural repair without compromising the beauty of the Victorian gable masonry.
AWT provides cost-effective structural repairs for a wide range of structural issues. Our specialist repair techniques make us the ideal choice for projects involving listed and heritage buildings.
We work together with structural engineers, architects and project managers to find economical and effective solutions. We operate not only in London but across the whole of the South East of England.
To book a time for one of our surveyors to visit your property or to discuss your requirements, call us today on 01227 721255, email us at enquiries@actionwallties.co.uk or use our contact form to get in touch.
Bulging & Cracking Brickwork Across Front of Victorian Semi Detached Houses
These 2 Victorian semi detached houses in Egham, Surrey had a significant bulge in the brickwork above the first floor windows. There was also a failing brick arch lintel and cracking to the brickwork. Without swift action the masonry would collapse.
AWT were called in to repair the defects and allow the homeowners to avoid slow, expensive and disruptive rebuilding work. Equipment designed by AWT was used to realign the brickwork, stabilise and reinforce the masonry and then install new wall ties and lateral restraints.
The Structural Problem
The AWT survey team visited the property in Surrey, TW20 to identify the root cause of the visible bulging of the masonry at the front of the property. The AWT survey team quickly identified that this Victorian semi was built using cavity wall construction and that failing cavity wall ties were likely a root cause of the problem.
A limited inspection of the wall ties was undertaken by drilling 12mm holes in the outer leaf of brickwork to view within the cavity via an endoscope. This confirmed the diagnosis of failing wall ties, as can be seen from the photos taken with the endoscope, as the corrosion of the metal was clearly visible. The mild steel ties were all in a similarly heavily corroded condition and showing signs of de-laminating.
Horizontal cracking, lifting and opening up of joints was noted at irregular intervals on the front elevation. Metal ties were located behind the cracks, with an electronic wall tie locator.
Corrosion of the embedded mild steel wall ties was causing them to expand to many times their original size. This was damaging the outer leaf of brickwork, splitting the bed joints and causing either lifting or bowing of the walls and damage to internal finishes. This left the wall vulnerable to vertical and wind loads, especially such a large gable wall.
Without structural repairs the wall would continue to bow further and eventually collapse. Traditional building methods would have required the partial deconstruction and rebuilding of the front of the properties.
The Structural Repair Solution
Unlike some cavity wall tie repair contractors, AWT always works to the standards laid out in the Building Research Establishment Specification Digest. This means that the separation between new wall ties, the layout pattern of the new wall ties and the material used to manufacture the new wall ties all meet the highest standards to ensure a safe, long term structural repair.
To avoid failure of the brickwork and brickwork arch AWT realigned the bulged brickwork, installed new stainless steel wall ties, isolated the old ties to prevent them causing further damage and formed a composite beam within the external brickwork. The formation of deep masonry beams within the existing masonry supports the masonry and maintains the integrity of the brickwork.
AWT use their own custom designed hydraulic realignment equipment and diamond bladed precision drilling rigs. This allows the new fixings to be installed with minimal disturbance to the masonry. A variety of specialist fixings were introduced into the brickwork to restore the strength and stability of the wall.
As can be seen in the photo above, when the work is complete there are no visible fixing either inside or outside the property. The AWT team also take the time to colour match any replacement bricks as well as matching the colour, texture and pointing style of the mortar where work has taken place.
AWT provide cost effective structural repairs for a wide range of structural faults including failing cavity wall ties and bulging brickwork. We operate not only in Surrey but across the whole of London and the South East of England.
To book a time for one of our surveyors to visit your property or to discuss your requirements, call us today on 01227 721255, email us at enquiries@actionwallties.co.uk or use our contact form to get in touch.
The owners of this Victorian / Edwardian end of terrace home in the Redbridge area of North East London called in AWT because of the significant outward bulging of the large gable wall of their property. There was also cracking to the internal gable end walls as well as to the internal party wall between the property and its neighbour.
The Structural Problem
The AWT survey team visited the property in Woodford Green to identify the root cause of the visible bulging movement of the large, solid brickwork flank/gable wall. Due to aging, ineffective and inadequate restraining of the brickwork the entire gable wall was de-bonding and disconnecting with the rest of the masonry. This was leading to additional problems with the internal beams losing support.
Without structural repairs, the large gable wall would continue to pull away and eventually collapse. Traditional building methods would have required the partial deconstruction and rebuilding of the flank wall. Even then, it would not have solved the root cause of the problem – inadequate restraining of the gable wall.
The Structural Repair Solution
The team at AWT designed a structural repair package that would bring the brickwork back into alignment and add tensile strength to the structure. The specialist tools and fixings used by AWT enable them to restore the brickwork’s integrity without visible fixings or rebuilding work.
Bed joint reinforcement beaming, grout tie injection and lateral restraints were employed to reinstate the uniformity of the wall and provide restraint. The formation of continuous beams within the existing masonry redistributed the upper storey loads while at the same time assisting in restraining diagonal cracking and bulging tendencies.
A specialist drilling rig, designed by AWT, was used to drill through the brickwork at a shallow angle to maximise the number of bricks connected by each helical, grout bonded fixing. The internal timber beams were reconnected to the masonry using resin bonded stainless steel fixings.
Cracked and disturbed areas of mortar were raked out and replaced with fresh mortar that was matched for colour, texture and pointing style.
AWT provided a long term solution for the bowing gable brickwork. By targeting the repairs exactly where they were required the work was completed swiftly and with minimum inconvenience to the residents. The hidden fixings used by AWT preserved the beauty of the old yellow stock brickwork.
Action Wall Ties are structural repair contractors with the specialist skills required to reinforce and repair large areas of bowing and bulging brickwork. AWT work along with property owners, architects, project managers and local authorities on large and small projects.
AWT are available in Kent, London, Essex, Surrey and Sussex. To arrange a survey or to discuss project details, please use our contact form, email us or call us on 01227 721 255.
AWT was called in to investigate a bulging gable wall and cracked ceilings at the end of a terrace in Walthamstow, East London. A structural repair solution was needed that would not require the removal of the Spar pebble dash render.
The Structural Problems
The homeowner called in AWT due to cracking in the internal walls and ceilings near the gable wall in this terraced home in London E17. Significant external outward bulging of the gable wall was also visible.
Gable wall problems are common in properties of this age and type. Ineffective and inadequate restraining of the gable masonry combined with ageing allows the gable brickwork to bulge and bow outwards.
A cost-effective solution was required that would restore the structural integrity, if possible without the need to remove the Spar pebble dash render from the gable wall.
If structural repairs are sought early enough, as in this case, AWTs specialist repair techniques may allow for repairs without removing the render/pebble dash. The small disturbed areas of render/pebble dash can then be made good with a concrete repair mortar system.
Standard building methods would require at least partial removal of the render and then re-rendering afterwards. Removal of the pebble dash render would have added to the expense and inconvenience for the householder. The access to the gable wall was also less than ideal.
The Structural Repair Solution
Location of Fixings
AWT used precision drilling techniques to embed fixings within the masonry with the minimum disturbance to the pebble dash finish.
Bed Joint Reinforcement Beaming: As shown by the red dotted line, stainless steel fixings were introduced into the masonry to form a deep masonry beam that redistributed the load from the upper storey and restored structural strength.
Grouted Tie Injection: As shown by the green lines, precision drilling techniques were used to install helical, stainless steel, grouted ties to restrain the gable brickwork.
Lateral Restraints: As indicated in yellow, stainless steel, resin bonded restraints were fitted to tie the gable wall masonry to the timber joists. This further restrained any tendency for the brickwork to bow outwards.
Re-pointing Disturbed Areas: AWT colour matches the mortar that is used to re-point disturbed areas and drill holes.
As can be seen from the after photo, the structural repairs to the bowing gable are barely visible. The pebble dash rendering remains intact and the underlying structural defects have been dealt with in a cost effective manner.
Before Repairs
After Repairs
For fast, effective solutions to bowing gable walls and other structural problems contact AWT today. AWT can advise on structural repairs to properties with render, pebble dash and spar dash. We provide professional solutions to a wide variety of structural issues for homeowners across London, Kent, Surrey and Sussex. Contact us on 01227 721 255, or email us.
This period property in Hampstead, North West London had significant structural defects due to a failing Bressumer beam over the bay window area. The entire bay window area and the decorative gable wall above was leaning away from the main structure. Without professional structural repairs, this would result in the ultimate failure and collapse of the structure.
The Structural Problem
This front elevation of this home in London, NW3 was at risk of collapse. The first floor timber Bressumer beam over the bay window was failing, causing the downward movement of the central column of brickwork. This resulted in significant distortion to the window cills, lintels and first floor causing them to lean down to the centre of the building.
This type of horizontal wooden beam is known by a number of different names including:
Timber lintel
Bressumer or Bressummer
Breastsummer
Summer Beam
Various other spellings including Sommer, Somer, Sommier and Somier
This type of substantial wooden beam is often found in period properties over bay windows supporting the building above and above shop windows.
Victorian timber Bressumer beams over bay windows are generally over stressed compared to modern day standards. They are often affected by Creep with significant deflection together with further deterioration of the timber due to rot, damp, pest infestations etc. This can render the beam ineffective, deflecting the brickwork above, as well as the floor and the ceiling, requiring remediation. Another common cause of Bressumer beam problems is movement within the building’s structure which leaves the beam lacking adequate support.
Many of the common symptoms of a failing timber bay window beam were clearly visible including:
Significant deflection of the beam
Cracking, bulging brickwork above
Masonry leaning away from the main elevation
Cracking internal plaster
Bulging ceilings
Sloping floors
Bowing of the main roof
Distorted window cills
Distorted window lintels
The entire bay window and the decorative gable brickwork was at risk of collapse. Traditional building methods would have required substantial and costly rebuilding work. Without AWT this would have required a major building project to de-construct the front elevation down to the Bressumer beam, replace the beam and thereafter rebuild the front first floor brickwork complete with window cill, lintels, refitting the windows and replacing internal plastering and finishings.
AWT was called in to stabilise the structure and preserve the period features. AWT’s specialist tools and structural repair skills enabled them to restore structural integrity without the need for rebuilding work, saving time, money and disruption.
The Structural Repair Solution
AWT used specialist equipment to realign the masonry, replace the wooden Bressumer lintel with a steel beam and install restraints. A lateral gable beam was also installed, the bulging gable wall was realigned and the structural integrity was restored.
Traditional building methods often provide a superficial, temporary solution. AWT’s structural repairs get to the root cause of the structural failings.
The structural repair works included:
Installation of temporary supports
Removal of failing Bressumer beam
Installation of new steel Bressumer lintel
Installation of lateral gable beam
Realignment of masonry by 70mm using hydraulic equipment
Bed Joint Reinforcement
Lateral restraints
Re-pointing disturbed areas with colour matched mortar
The remedial works restored the leaning masonry to its vertical alignment and restrained it from leaning outwards. The new steel Bressumer beam, lateral gable beam and the Bed Joint Reinforcement within the masonry restored the strength of the structure.
AWT provided a permanent solution to the structural defects without the need for expensive rebuilding work or visible fixings.
Satisfied Customers
The first photo below shows the re-plastered ceiling ready to be repainted and the second shows it after redecoration was completed. The beautiful period features of the house can be enjoyed in their former glory.
The home owners were delighted with how hassle free the process was and at the finished results.
Some of their comments were:
“You managed to diagnose pretty much what was wrong over the phone without having seen a photo i.e. Bressumer beam failure. We felt we were dealing with a professional company with a real idea of what we would need.”
“Your surveyor, Scott, was again reassuring. He gave the impression that whilst our house was of concern it was nothing compared to some properties you’ve repaired and it wouldn’t be beyond you.”
“Once we agreed to go ahead you were again very supportive and we felt comfortable and confident that we were in good hands.
The building team you that sent us were very reassuring and immediately had our confidence. The entire team were polite and professional and inspired confidence.”
“My elderly neighbour 2 doors away asked me when the works were starting and I was happy to tell her they were already finished….”
“We have a family friend that was very concerned with us walking blindly into a massive building program with no clue as to what we were doing and that it could all go horribly wrong. I’ve been very pleased to let him know everything went better than expected and AWT completed the works quicker than we hoped. It’s all been a very positive experience.”
AWT provide cost effective structural repairs for a wide range of structural faults including failing wooden beams and lintels. We operate not only in NW London but across the whole of London and the South East of England.
To book a time for one of our surveyors to visit your property or to discuss your requirements, call us today on 01227 721255, email us at enquiries@actionwallties.co.uk or use our contact form to get in touch.
Repairing Distorted Gable Brickwork & Large Gaps Around Bay Window Glazing.
The masonry of the bay window of this property in London E11 was leaning away from the main structure. Large gaps were opening up between the bay window frames and the double glazing units. Realignment of the sagging bay window plus reinforcing failing gable brickwork to restore structural integrity were required.
The skills of the AWT team allowed them to restore the structural integrity in a cost effective and efficient manner without any rebuilding or visible fixings.
The Structural Problem
This East London home had visible cracking in front bay window brickwork and stone lintels. Outward rotation of the first floor bay window was clearly visible. Large gaps had opened up between the bay window frame and the glazing. The cracking and distorting of the masonry bay had caused significant movement to the brickwork gable above.
Problems of this type are common in such Victorian / Edwardian properties and are usually the result of ageing and inadequate restraining in the original building methods.
The AWT also had to be prepared for the possibility that the masonry components might not be solid masonry but simply a thin facade covering a timber frame.
The Structural Repair Solution
After the initial inspection, the AWT team conducted an intrusive survey by drilling carefully placed inspection holes and using an endoscope where necessary. This allowed them to determine that this property’s bay window was constructed using solid masonry elements.
The first element of the structural repairs required the installation temporary supports to the underside of the first floor bay window lintels. AWT designed realigning cramping equipment and hydraulic powered jacks were used to realign the columns and brickwork ready for reinforcing.
Specialist drills were used to introduce rows of 8mm stainless steel corded joint reinforcement fixings. This redistributed the upper storey load to the supporting structure below and restrained the diagonal cracking and bulging tendencies.
Precision drilling rigs were used to install helical stainless steel pins through the brick arch. Resin bonded stainless steel pins were used to reconnect the brickwork to the main body of the building.
Internal gable restraints were fixed in place. Stainless steel lateral restraints were installed directly into the timber joists and resin bonded to the masonry. This restored the structural integrity of distorted gable brickwork.
Any disturbed mortar was re-pointed with mortar matched for colour and texture to blend with the existing pointing.
For a fast, effective solution to bay window structural problems contact AWT today. We provide professional solutions to a wide variety of structural problems for home owners across London, Kent, Surrey and Sussex. Contact us on 01227 721 255, or email us.
Concrete boot lintels to window openings were in common use in the 1970s and have the unique appearance of a visible one course high concrete toe that appears not to have any bearing onto the adjacent brickwork (i.e. the visible concrete toe is in between the brickwork reveals).
Many low rise blocks from the 60s and 70s develop defects that require concrete boot lintel repairs due to cracks, gaps and sagging brickwork above the windows. Failure to address these issues promptly can lead to dangerous, collapsing masonry as well as extensive damage to internal walls.
AWT are able to provide long term, cost-effective boot lintel repairs with minimal disruption to residents.
Concrete Boot Lintel Problems
Rotating Boot Lintel Causing Gaps & Cracks
Stepped Cracks Due To Failing Boot Lintel
Gaps Above Concrete Boot Lintel
Boot Lintel Defect Causing Compression Cracks
As shown in the gallery, in the 60s and 70s, many concrete boot lintels were incorrectly fitted onto unsuitable bearing allowing the lintel to rotate and the supported brickwork to drop and crack.
This fundamental flaw in the installation of concrete boot lintels means that the weight of the heavier brick outer skin is too great for the relatively soft and lightweight inner blocks to support. The lintel rotates, causing gaps to open up, compressing the blocks of the inner wall and causing the outer brickwork to sag.
Common symptoms of boot lintel problems:
Cracks in the visible part of the concrete lintel
Stepped cracks in the brickwork above windows/doors
Dropping of the brickwork above windows/doors
Bulging or bowing brickwork above windows/doors
Cracks in the internal walls and ceilings above windows/doors
Warped window/door frames making them difficult to open and close.
Chris Nichols explains, “This type of lintel has no bearing onto the external brickwork the concrete lintel rarely fails. (As with any concrete the toe of a boot lintel can be affected by corroding reinforcing bars and require concrete repairs.) The boot lintel is reliant on the bearing onto the internal skin. The internal skin bearing the lintel should be of a material capable of withstanding and spreading the load (e.g. pad stone concrete blocks or engineering bricks). “
“In many cases the lintel was bedded directly onto lightweight blocks that are unable to take the imposed load and compress the outer edge of the bearing, rotating the lintel and allowing the external brickwork above to crack and drop as described in BRE Good Building Guide 1.”
Cracking Concrete Boot Lintels
Gaps & Cracks Above Concrete Boot Lintel
Gaps & Cracks Around Concrete Window Lintels
Rotated Boot Lintel Causing Gaps
Boot Lintel Problems Due To Incorrect Installation
Concrete Boot Lintel Repairs
Action Wall Ties provide a cost-effective, long term solution that retains the existing appearance of the brickwork with the minimum disruption to the occupants and the environment.
Action Wall Ties have developed a remedial system and methods, including specifically designed equipment, to remedy the problem of cracked concrete boot lintels. Action Wall Ties slightly anti-rotate the lintels back in place, drilling for and then resin bonding 16mm stainless steel shear pins to both end bearings. Once the resin bonded fixings are set the props are released, pre-loading the shear pins, thus reducing any further cracking.
To larger openings and with advanced movement it may be necessary to introduce two rows of twin cord reinforcement, forming a composite deep masonry beam. To the underside of the concrete toe, we drill for and inject grouted 8mm helical stainless steel pins passing into the line of the deep masonry beam to arrest any further rotation of the concrete lintel.
Action Wall Ties concrete boot lintel repair and replacement solutions are available to clients in London and the South East.
Action Wall Ties (AWT) are specialists in masonry reinforcement and repair, lintel repairs, replacing a damaged lintels, and providing professional solutions to a wide variety of structural problems. We work with home owners, London boroughs, social housing providers, architects, project managers, local authorities and insurance companies.
Victorian semi-detached house with very large bowed flank wall. AWT used bed joint reinforcement, lateral restraints and resin bonded ties to realign and stabilise the bowing brickwork. As with many properties that AWT is called in to repair, the property showed signs of previous repairs that had failed to address the underlying structural issues.
The Structural Problem: Bowing Flank Wall
This substantial Victorian traditionally built semi-detached house is a domestic residence spread over three floors. As shown in the photo, the flank wall had a significant visible bulge in the centre of the wall at first-floor level. No significant cracking was noted. The third floor (top level) appeared to have been rebuilt.
The AWT survey team judged the movement of the masonry to be progressive and in need of stabilisation to avoid the entire wall collapsing. The previous rebuilding of the third floor brickwork failed to tackle the weakness in the structure that was allowing the brickwork to bow outwards.
What Causes Bowed Brickwork?
As is common with Victorian properties, the bowing masonry was due to some downward movement compounded by ineffective or inadequate restraining. Under the weight of the masonry above, and without strong enough fixings to tie it to the main body of the property, the brickwork bulges outwards.
The bulge may have been formed by some de-bonding of the brickwork (or cracking of the headers). It was common practice in buildings of this age for a 9-inch wall to be constructed as two half-brick walls with snapped headers to the external skin to save on expensive facing bricks. This results in a less structurally stable wall, compared to fully bonded brickwork, because the inner and outer skins of the wall are only connected by mortar.
The Structural Repair Solution
AWT’s remedial scheme involved the introduction of bed joint reinforcement, lateral restraints and resin bonded ties (see coloured remedial works on our proposal picture.) This added tensile strength and reinstated the brickwork’s integrity and the uniformity of the wall. After installation, the pointing was raked out, reinstated and tinted to match the existing.
1. Bed Joint Reinforcement:
The AWT team installed two rows of twin cord reinforcement, forming a deep masonry beam – indicated by red double dotted lines in the image.
2. Lateral Restraints:
In conjunction with the beam, 8mm stainless steel lateral restraints were introduced and screwed directly into timber floor joists’ end grain or into the side grain and resin bonded to the masonry – indicated with yellow stars in the image.
3. Wall Ties to De-bonding Brickwork:
Using specialist precision drilling rigs, the AWT team drilled for and installed new resin bonded, 6mm stainless steel remedial ties – indicated with blue lines in the image. Disturbed areas were re-pointed with colour matched sand and cement mixture.
Cost Effective Structural Repairs
Rebuilding work would have been, slow, messy and expensive. The affected rooms would also have been uninhabitable during the rebuilding work.
AWT was able to provide a long lasting structural repair that got to the root cause of the bulging brickwork. The bowing masonry was strengthened and brought back into vertical alignment. No visible fixings or rebuilding work was required. The vast majority of the work was carried out from the exterior of the property thus minimising the disturbance to the residents and to interior finishes.
Action Wall Ties (AWT) based in Canterbury, Kent, are specialists in masonry reinforcement and repair, providing professional solutions to a wide variety of structural problems in London and Kent. Contact us on 01227 721 255, or email us.
