When AWT surveyed this 1970s cavity wall bungalow in Canterbury it was obviously in a perilous condition. The gable walls at either end of the property were leaning far beyond the tipping point. Urgent action was required to prevent collapse.
AWT provided a permanent and cost-effective structural repair without rebuilding work on the walls or removal of the roof.
Distorted Roof & Leaning Gable Walls
The Structural Problem
The roof structure including the roof trusses and both brickwork gable walls were leaning precariously to the left. The walls were some 250mm/9.8 inches from vertical. This is far beyond the tipping point and makes structural collapse inevitable.
Leaning Gable WallSevere Lean in Gable WallsLeaning Gable Brickwork
Inspection of the roof revealed no braces had been installed on the roof trusses. The roof tiles, fascia boards and soffits had warped with the structural movement but remained intact. The property also lacked effective wall ties.
These deficiencies in the original construction left the gable walls unrestrained. Over time, the weight of the roof structure and the heavy roof tiles caused the gable walls to lean significantly.
During Wall RealignmentDuring Brickwork RealignmentDuring Gable Straightening
AWT designed and installed temporary steel anchors on the right side of the building and attached steel frames to both gable walls. The structure was realigned using AWT’s specialist hydraulic and screw-powered jacks. This shifted the gable brickwork, roof, fascias and soffits back to the vertical position.
To ensure a permanent repair, AWT installed roof truss braces and wall ties. The brickwork gable walls were reinforced and restrained to prevent leaning.
Disturbed areas of mortar and damaged bricks were repaired with carefully matched replacements. The result is a nearly invisible repair with no visible fixings, no rebuilding work and minimal disruption for the residents.
After Gable Wall RealignmentAfter Structural Repairs to Gable
AWT provides cost-effective structural repairs for a wide range of structural issues. Our specialist tools and techniques allow rapid and permanent structural repairs without the high price and disruption of rebuilding work.
We work with structural engineers, architects and project managers to find economical and effective solutions. We operate not only in Kent, but across London and the whole 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.
This 4-storey period property in Stratford, East London had been converted into flats. The large brick flank wall had significant outward bulging, with corresponding internal movement, resulting in cracking in the front and rear elevations. Without prompt structural repairs, the defect would worsen causing the property to be condemned as unsafe for occupation.
Bulging Side Wall
The owners and their structural engineers contacted Action Wall Ties to assist in designing and completing structural remediation works. Action Wall Ties, working with the consulting structural engineers, designed a practical stabilisation method that maintained the internal layouts.
The Structural Problem
This semi-detached Victorian/Edwardian property in London had been converted into a house of multiple occupation (HMO). The building had undergone extensive internal remodelling, including the complete removal of the original central spine wall, which had been replaced with steel beams. A survey found visible outward bulging of the large brick side wall, plus internal movement and cracking in the front and rear elevations.
As with many properties with structural defects, previous repair attempts had provided only short-term, cosmetic repairs but failed to tackle the underlying issues. As shown in the photo, the brickwork had bulged by well over 2 inches/5cm between floors.
Serious Bulge in Wall
Bowed Side Wall Causing Cracks
Consulting structural engineers reported that the central spine wall had been removed at the upper ground, first, and second-floor levels. The floors have been re-supported with steel beams. Originally, the central wall would have acted as a shear wall, providing horizontal stability to the building and preventing it from raking/leaning. Its removal has meant inadequate provision for horizontal stability in the central part of the building. This situation is believed to contribute to or worsen the bowing in the flank wall, presenting a significant structural problem that jeopardizes the building’s integrity. If not addressed, this issue is expected to worsen, potentially making the building a safety risk to the occupants.
The Structural Solution
Action Wall Ties, working with the consulting structural engineers, designed a practical stabilisation method that maintained the internal layouts of the flats. This involved forming braced diaphragms on each floor, incorporating the existing replacement steel beams, and introducing fabricated steel angles with welded junctions at ceiling line perimeters. This method reinstated horizontal stability to the central area in compliance with Document A of the building regulations regarding disproportionate collapse.
AWT worked with the structural engineer to design the steel work which was fabricated and delivered to the site. This allowed the on-site structural steelwork and brickwork to be completed in 2 weeks.
AWT Designed Steel Reinforcement
The consulting engineers initially recommended two options to restore horizontal stability to the central area of the building while maintaining the internal layouts. However, both options would be disruptive, requiring tenants to move out for an extended period during the work. The owners were keen to find a solution that would not require changing the floor plan of the flats, as this would lead to additional costs and impact the sale/rental values.
The first option suggested by the consulting engineers was to install a three-story steel frame throughout the building, providing the necessary horizontal stiffness. If the existing beams were perfectly aligned (which is unlikely), it might be possible to use them with steel posts installed between them. However, misalignment of at least one beam is probable, leading to non-vertical posts. The second option was to rebuild the central spine wall in blockwork, possibly retaining the existing beams. This option would alter the layouts of the upper flats. It was noted that tying the flank wall to the floor plates and walls would be pointless without addressing the shear wall problem, necessitating both measures to stabilize the building. AWT collaborated with the consulting engineers to find a long-term, cost-effective structural repair solution that minimises disruption to the tenants.
Steel Braces
Installing Steel Beams
Structural Reinforcement
Bracing Steelwork
Wall Braces
AWT Designed Steel Reinforcement
Working with the consulting structural engineers, Action Wall Ties collaboratively designed a practical method of forming braced diaphragms on each floor. This method incorporated the existing replacement steel beams and involved adopting fabricated steelworks welded in situ. This approach maintained the benefits of the internal layouts while reinstating horizontal stability in the central area, in accordance with Document A concerning the disproportionate collapse of the building.
Structural Repairs
Bracing Bars
Structural Steel Beam
Welded Steelwork
Diagonal Braces
Steel Structural Restraints
The steel braces restored the structural integrity of the building and realigned the brickwork. The property was left ready for the reinstatement of the internal finishes. Once replastering, repainting etc was completed, no fixings were visible inside or outside the property. AWT provided a long-term structural repair that preserved the floor plan of the flats and protected their sale/rental values.
Diagonal Flat Bar Bracing
Welded Steel Angles
In-situ Steel Welding
During Brickwork Realignment
Structural Reinforcement
Bracing in Ceiling Void
Action Wall Ties are specialist structural repair contractors with the knowledge and experience required to repair period properties with severe masonry defects, such as bulging brick walls. AWT work with structural engineers, property owners, architects, project managers and local authorities on both small and large projects.
AWT are available across London, Kent, 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.
Remedial Wall Ties & Boot Lintel Repairs for 60s/70s House in Thanet
This detached house in Broadstairs, Kent, has a typical 1960s/1970s design and construction. Many similar properties are now developing the same structural problems.
A structural survey of the property indicated issues with the concrete boot lintels and the wall ties. The new owners called in AWT to stabilise the superstructure and protect their investment. Prompt structural repairs prevented the structural defects from causing further damage and avoided more extensive repairs.
Failing 60s/70s Boot Lintels
How to Identify Boot Lintels
Failing Wall Ties
The door and window openings were constructed using concrete boot lintels; easily identifiable by the distinctive concrete beams above doors/windows that do not extend beyond the width of the opening. Concrete boot lintels are prone to rotate. This had caused cracking in the internal plaster and cracked, open mortar joints in the external brickwork. The original cavity wall ties were also failing, leaving the outer brick skin unrestrained, and vulnerable to bulging/failure.
The Structural Problem
The property was suffering from 2 main defects that are very common in 1960s/1970s properties; rotating concrete boot lintels and failing wall ties.
Rotation of Boot Lintels:
A fundamental flaw in the installation of concrete boot lintels in 60s/70s properties means that the weight of the heavier brick outer skin is too great for the softer inner blocks to support. The boot lintel rotates, causing gaps to open up, compressing the blocks of the inner wall and allowing the outer brickwork to sag.
The early symptoms of boot lintel problems, as seen below, are cracks in the internal plaster above or radiating from the top corners of doors and windows. It also caused cracking and distortion of the supported brickwork above the doors and windows.
Failing Boot Lintels
Cracks Above Doors/Windows
Cracks Above Window
Cracks in Window Plaster
Common symptoms of concrete boot lintel problems:
Cracks in the internal walls and ceilings above windows/doors
Warped window/door frames – difficult to open and close
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
Traditional building repairs – making good the cracks and open joints – treat the symptoms, not the cause. If the rotation continues, serious damage caused by the rotation may result in the necessity to replace the lintels. To avoid further damage to the brickwork, the boot lintels require specialist structural repairs.
Rotating Boot Lintel Causing Gaps & Cracks
Stepped Cracks Due To Failing Boot Lintel
Gaps Above Concrete Boot Lintel
Boot Lintel Defect Causing Compression Cracks
Failing Wall Ties & Inadequate Restraint:
Investigation of the wall ties revealed the existing Wire Butterfly Ties were in varying stages of corrosion and were beyond their useful life. The building had suffered some movement for a prolonged period and was progressive due to a combination of ageing, ineffective and/or inadequate wall tying and restraining plus the effect of rotating fenestration boot lintels all contributing to a lack of structural stiffness.
The progressive corrosion of the existing wall ties left the property vulnerable to vertical and wind loads, especially to large gable and unreturned walls. Instability of the wall will result if the ties corrode away completely, resulting in a need to rebuild the wall. Prompt action to install remedial wall ties will avoid more costly and disruptive repairs in the future.
Plaster Cracks in Corners
Vertical Plaster Cracks
The Structural Repair Solution
The structural repairs by AWT tackle the root cause of the masonry defects and add tensile strength thus reinstating the brickwork’s integrity.
Structural repairs included:
Bed Joint Reinforcement Beaming
Fenestration Boot Lintel Treatment
Grout Tie Injection
Remedial Wall Ties
The AWT team installed specially developed prop supports to anti-rotate the boot lintel back into place. Specialist diamond drilling techniques were used to drill through the brickwork into the boot lintel and install resin-bonded stainless steel sheer pins.
Concrete Boot Lintel Repairs
Repaired Boot Lintel
New pad-stones were installed by providing temporary support to the underside of the lintels, carefully removing sufficient plaster to expose the lintel, cutting out the internal skin and forming a pad-stone to spread the load onto the internal skin. The area was left ready for plastering.
The new wall ties, bed joint reinforcement beaming and grouted ties stabilised the superstructure, reconnecting the inner and outer walls and strengthening the overall structure.
AWT provide cost-effective structural repairs for a wide range of structural problems including failing wall ties and concrete boot lintel problems. We operate not only in Kent 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.
Victorian Bay Window & Balcony: Structural Repairs & Restoration
This beautiful example of ornate Victorian architecture in Thanet was at risk of imminent collapse due to severe structural issues. The property had visible significant movement including bowing, cracking, dropping of brickwork arches and bowing columns of the front bay window and to the front elevation.
Several companies had surveyed the problems but none offered any solutions. Previous repairs to the property had tackled the symptoms of the structural defect but had failed to cure the root cause of the problem.
It took just 2 weeks of work for AWT to complete a cost-effective, long-term structural repair. Compared to rebuilding work, the disruption to the residents was minimal.
Before Structural Repairs
After Structural Repairs
The Structural Problem
The structural issues with this period property in Thanet, Kent were clearly visible. Wide gaps had opened up between the masonry and the window frames. The structural defect had caused damage from the ground floor bay window columns up to the decorative brickwork panels below the eaves. This entire section of the property was in severe danger of collapse.
Bay Window Issues
Sagging Bay Masonry
Gaps & Cracks in Brickwork
Dropping Bay Arches
Dropping/Cracking Brick
AWT’s inspection of the front bay window found significant distorting movement to the front ground floor causing:
outward movement
dropping and cracking of the brickwork arches and stone quoins
significant outward bowing of brickwork columns beyond the tipping point
Bowing Bay Columns
Gaps Around Windows
First Floor Masonry Issues
Inspection of the front elevational brickwork found signs of distorting movement of the ground floor supporting bressummer beam (over the bay window) causing:
dropping of the supported main elevational brickwork
dropping brickwork pier stone quoins
dropping window arches above the bay window
inward sloping and cracking of the brickwork above the bay window
As part of previous attempts to halt the movement of the masonry, the bressummer beam over the bay window had been replaced by an old-style RSJ.
Distorted Window Arch
Failing Brickwork
Bay & Portico Balcony Issues
Broken Stone Capping
Cracked, Crumbling Stone
Missing Stone Capping
Ugly Concrete Capping
The owners also wanted to deal with some aesthetic problems with the bay and portico balcony balustrade’s decorative wrought iron panels and stone top rails. All the panels required refurbishment. The bay window’s stone top rail had been replaced with an unattractive concrete capping. The portico stone top rails were mainly missing. New stones, in keeping with the period features, were needed to complete the restoration.
The Structural Solution
Bay Realignment
Bay Reinforcement
Steel Spine
Stonework Repairs
Replacing Stone
New Capping
AWT recommended realigning and reinforcing remediation work to the existing brickwork including:
brickwork realignment
bed joint reinforcement
brickwork arch repair
diamond drilled grouted anchors
lateral restraints
grout tie injection
stonework & brickwork repairs
addition of fabricated steel spines to the columns
addition of an internal restraint post to the first floor
This multi-faceted approach reinstates uniformity and provides restraint to the masonry.
Fully Repaired
Repaired Bay Window
Realigned Bay Window
Bay & Balcony Repairs
Realigned Bay Columns
No More Gaps
AWT also carefully removed the balcony balustrade panels for refurbishment. The lugs were replaced with stainless steel before the panels were grit blasted, powder-coated black and refitted. The brickwork corner piers were rebuilt. Finally, AWT had replacement capping stones cast in a limestone material with stainless steel reinforcing and bedded them in position.
Fast, Cost-effective, Minimal Disruption, Long Term Structural Repairs
Tackling such serious structural issues using traditional building techniques would have required reconstruction and rebuilding of the front of the property. Rebuilding would have been expensive, slow and highly disruptive to the homeowners. Damage to the original bricks and ornate stonework would be inevitable.
In just 2 weeks, AWT’s long-term repairs were completed without major rebuilding work or visible fixings to mar the internal or external period features.
Balcony & Brick Repairs
After Ballustrade Repairs
After Arch Repairs
After Bay Reinforcement
Action Wall Ties are specialist structural repair contractors with the skills and experience required to repair and restore period properties. AWT works on large and small projects for property owners, structural engineers, architects, project managers 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.
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.
Bressumer Beam Replacement & Masonry Realignment Without Demolition
Before Realignment
After Realignment
The masonry at the front of this mid-terraced home near Croydon, London, was sagging in the middle due to a failing bressumer support beam above the bay window. The distortion was clearly visible outside the property, with the distortion of the windows giving it a cartoon-like sad expression. Inside the property the floors were sloping and walls and ceilings cracking.
Dropping Brickwork & Windows
Sagging Windows
Distorted Windows. Failing Bressumer Beam.
Sloping Floors. Failing Bressumer Beam.
Sloping Windows. Failing Bressumer Beam.
The structural problem had progressed so far that it was bowing the main roof of the property. Without suitable structural repairs the property was at risk of collapse.
Traditional building works to repair such a serious structural fault would have required a major building project. Standard building methods would require de-construction of the front elevation, replacing the beam, rebuilding the front first floor brickwork, refitting the windows and re-plastering inside.
The Structural Problem
Structural Repairs for Sagging Masonry.
Repairs to Dropping Windows
Ceiling Cracks due to Failing Bressumer Beam
During Bresummer Beam Replacement
This Victorian/Edwardian home in South East London had clearly visible structural distortion:
Significant visible distortion of the front elevational masonry
Dropping of the centre column of 1st floor brickwork
Significant deflection to the window openings, cills & lintels down to the centre of the building
Bowing of the main roof
Cracking to the internal plaster
Bulging of the ceiling
The AWT survey team rapidly diagnosed a failing bressumer beam. Bressumer beams are also known as bressummer beams, breastsummer beams, summer beams, timber lintels or wooden beams.
These large timber beams span openings, such as bay windows, and support the masonry above. They are often found in period bay windows and shop windows.
Failure of a Bressumer beam, due to deterioration of the wood or movement within the structure, can have serious knock-on effects on the building’s structural integrity.
Period timber Bressumer beams over bay windows are often over stressed by modern day standards. The load from the structure above causes the beam to creep or deform and causes significant deflection from the beam’s correct position. This, together with further deterioration of the timber due to rot, damp, pest infestations etc can cause the beam to fail, deflecting the brickwork, floor and ceiling above.
This was a serious structural defect significant and if it was not addressed it would result in the ultimate failure and collapse of the structure.
The Structural Repair Solution
AWT were called in to find an alternative to slow, expensive and disruptive rebuilding works. AWT have spent many years developing equipment and methods that allow structural repairs to be carried out that treat the root causes of the problem without demolition and rebuilding. This allows for a less disruptive, more cost effective repair solution.
After Bressumer Beam Replacement
During Bressumer Beam Replacement
After Bressumer Beam Replacement
After Masonry Reinforcement
AWT’s structural repair plan included:
Installation of temporary supports
Using AWT designed equipment to realign the bressumer beam, floor joists, brickwork, window cills and lintels
Removal of the existing timber bressumer beam
Formation of concrete pad stone supports
Installing a new steel beam
Masonry beaming – reinforcement of the brickwork using Bed Joint Reinforcement
Restraining bulging masonry by installation of resin bonded ties within the brickwork
Concrete and brickwork repairs
Matching replacement bricks, pointing style and mortar mixture for texture and colour
The property owners replaced the old, distorted windows in the future to complete the transformation.
Before Structural Repairs
Before Structural Repairs
After Structural Repairs
AWT left the property with hardly a sign of the extensive work visible on the outside of the property. Inside, there are no visible fixings. The disturbed areas of the internal wall and ceiling were left ready for replastering and redecoration. As can be seen in the photos, the internal finishes have been disturbed far less than would have been the case after repairs by traditional techniques.
Action Wall Ties are specialist structural repair contractors with the skills required to replace failing bay window beams, realign masonry and reinforce brickwork on modern, period and heritage properties. AWT work along with property owners, architects, project managers and local authorities on large and small projects.
AWT are available for projects of all sizes in London, Kent, 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.
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.
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.
Victorian mid-terrace house rear addition bowing and dropping brickwork – stabilisation, bed joint reinforcement beaming, crack stitching, fenestration lintel repair, grouted tie and lateral restraints
The subject building was a traditionally built Victorian mid-terrace domestic residence, consisting of three floors below a pitched tiled roof.
Problem
Signs of distortion and distress, with localised cracking, were noted to the far external gable wall of the rear addition – along with cracked and dropped brick arches to the first and second floor level. Previous repairs of old tie bars with patress plates, large steel straps, rebuilding and re-pointing were noted, indicating a history of movement.
A significant outward bulge to the side elevation at first floor level with localised cracking was also noted, as was significant downward movement at the rear doorway with all brickwork leaning towards that point.
Causation
The movement noted was attributed to subsidence, which may well be historic as internal redecoration shows no sign of cracking. Under these circumstances we did not consider that underpinning was warranted at this stage. Our pragmatic solution was to reinforce and tie back the building by using a combination of bed joint reinforcement and lateral restraints into the first floor construction to reinstate structural integrity.
Solution
AWT’s remedial scheme was the introduction of bed joint reinforcement beaming, crack stitching, fenestration lintel repair, grout tie injection and lateral restraints – adding tensile strength and restraint and thus reinstating the brickwork’s integrity and the uniformity of the wall. After installation, pointing was raked out, reinstated and tinted to match the existing.
1. Reinforcement:
We introduced two rows of twin 8mm stainless steel corded joint reinforcement to form a deep masonry beam – as indicated with red double dotted lines on our proposal images.
2. Grout tie injection:
We drilled into the party wall and bent into the hole one of the grouted 8mm stainless steel cords – as indicated with red stars on our proposal images.
3. Lintel repair:
To the underside of the fenestration openings head we drilled for and injected grouted 8mm helical stainless steel pins through the brick arch and passed into the line of the deep masonry beam installed within the existing masonry – as indicated with green parallel lines on our proposal images.
4. Crack stitching:
We stitched localised cracks with the introduction of single 8mm stainless steel corded joint reinforcement – as indicated with red single dotted lines on our proposal images.
5. Lateral restraints:
In conjunction with the beam, we introduced 8mm stainless steel lateral restraints screwed directly into the timber floor joists’ end grain or into the side grain, all resin bonded to the masonry – as indicated with yellow stars on our proposal images.
Action Wall Ties (AWT) are specialists in masonry reinforcement and repair, providing professional solutions to a wide variety of structural problems. Contact us on 01227 721 255, or email us.
Extensive superstructure reconnection and reinforcement after underpinning for a Victorian house in North West London.
The subject building was a substantial Victorian traditionally built semi-detached domestic house in London, NW3.
The Structural Problem
Click on the gallery images below to see the full extent of the damage caused by the structural issues. Evidence of previous, unsuccessful attempts to fix the structural issues by traditional building techniques can also be seen.
Signs of distortion and distress were noted, with localised cracked and dropped brick arches to the first and second floor levels of the square bay.
Significant cracking was noted to the external brickwork running from and to the ground, first and second floor window openings. The brick arch was missing from the first floor window and distortion, cracking and dropping were noted to the ground and second floor arches. The first and second floor window openings had temporary supports.
Causation
The movement noted was attributed to subsidence. Downward movement had allowed the brick arch to spread and drop and the brickwork to crack. The downward movement had been addressed by a recently completed underpinning scheme. Some de-bonding of the brickwork was also noted.
The Structural Repair Solution
1. Bed joint reinforcement:
We introduced two rows of twin cord reinforcement, forming a deep masonry beam – as indicated with red double dotted lines on our proposal images.
2. Lintel repair:
To the underside of the fenestration openings head we drilled for, and injected, grouted 8mm helical stainless steel pins through the brick arch, passing into the line of the deep masonry beam installed within the existing masonry – as indicated with green parallel lines on our proposal images.
3. Bay window repair:
To form a beam and reconnect the bay window elevational brickwork, we diamond-drilled a 20mm hole through each elevation, chased into the main elevation and injected grouted 8mm helical bars – as indicated with green horizontal parallel lines on our proposal images.
4. Crack stitching:
To stitch localised cracks we introduced single 8mm stainless steel corded joint reinforcement – as indicated with red single dotted lines on our proposal images.
5. Wall ties to de-bonding brickwork:
To brickwork within the beamed area and arches, where brickwork was believed to be de-bonding, we drilled for and resin bonded 6mm stainless steel remedial ties and re-pointed disturbed areas with a sand and cement mixture.
Signs of distortion and distress, with localised cracking, were noted to the external brickwork to the front entrance archway bridge, along with cracked voussoirs and the dropping of the brick arch and outward movement.
6. Resin bonded ties:
To stabilise the brickwork archway bridge, we introduced truss ties. To form the truss we drilled a 14mm hole at 45 degrees to the required depth, opened the entrance hole to 18mm, resin bonded 10mm stainless steel threaded rods, drilled a horizontal 14mm hole to the required depth, inserted the 10mm stainless steel threaded rods, fixed nuts and washers, resin bonded to the inner wall, tightened nuts to both sides and resin bonded to the outer brickwork.
7. Making good and pointing:
We raked out the existing mortar and repaired with new coloured sand and cement mortar to approximately 20mm in depth. AWT operatives are highly skilled in traditional building methods and always attempt to match replacement bricks, pointing styles and mortar colour to be sympathetic with the existing building.
High Quality Structural Repairs
The photos below show the property 14 years after the work was completed. The high quality structural repairs carried out by AWT are designed to last. Unlike traditional building repairs, our techniques get to the root cause of structural defects.
Action Wall Ties (AWT) are specialists in masonry reinforcement and repair, providing professional solutions to a wide variety of structural problems in Victorian properties in London, Kent and the whole of SE England. Contact us on 01227 721 255, or email us.
