Brick Arch failing, cracking, dropping Archives

Rebuild & Reinforce Collapsed Bay Window in SW London

SW8 bay window repair 225x300 - Rebuild & Reinforce Collapsed Bay Window in SW London — After Structural Repairs

Located in Wandsworth, SW8, this Victorian/Edwardian home had clearly visible dropping and cracking masonry around the ground floor bay window. Shortly after the initial inspection, the masonry failed and the brickwork of the bay window collapsed.

Previous attempts at repairs by re-pointing the brickwork were clearly visible but had failed to get to the root cause of the structural defect. AWT was able to stabilise the masonry before strengthening the structure and rebuilding the brickwork to provide a long-lasting repair.

Read our frequently asked questions about bay window structural repairs.

The Structural Problem

London bay window collapsed - Rebuild & Reinforce Collapsed Bay Window in SW London

SW8 bay window collapsed - Rebuild & Reinforce Collapsed Bay Window in SW London

London bay window sagging - Rebuild & Reinforce Collapsed Bay Window in SW London

SW8 bay window sagging - Rebuild & Reinforce Collapsed Bay Window in SW London

Bay structural reinforcement - Rebuild & Reinforce Collapsed Bay Window in SW London

Bay structural strengthening - Rebuild & Reinforce Collapsed Bay Window in SW London

Collapsed Bay Window, London

Collapsed Bay Window, SW London

Sagging Bay Window, London

Sagging Bay Window, SW London

Bay Window Structural Reinforcement

Bay Window Structural Strengthening

AWT was called in to survey this mid-terraced, period property in Greater London. The ground floor bay window masonry and brickwork arches had visible cracking, dropping and significant outward leaning. A large gap had opened up between the brickwork columns and the box sash windows. This serious lack of structural integrity was also causing the 1st floor brickwork to bulge.

The photos show the warning signs that owners of similar properties should look for that warn of serious structural defects in bay window brickwork and the risk of collapse.

Just 2 days after the initial survey, the ground floor right-hand column and arch, the front arch plus the supported external skin of brickwork collapsed. This left the brickwork above unsupported and at imminent risk of failure. Urgent action was required to avoid the collapse of the entire front elevation.

The root cause of the structural defects was a combination of aging and inadequate restraining.

The Structural Repair Solution

Collapsing bay masonry - Rebuild & Reinforce Collapsed Bay Window in SW London

dropping bay arch - Rebuild & Reinforce Collapsed Bay Window in SW London

bay window gap - Rebuild & Reinforce Collapsed Bay Window in SW London

dropping bay masonry - Rebuild & Reinforce Collapsed Bay Window in SW London

rebuilding bay brick arch - Rebuild & Reinforce Collapsed Bay Window in SW London

rebuilding bay brickwork - Rebuild & Reinforce Collapsed Bay Window in SW London

after bay rebuilt - Rebuild & Reinforce Collapsed Bay Window in SW London

rebuild bay window - Rebuild & Reinforce Collapsed Bay Window in SW London

Collapsing Bay Masonry

Bay Window Arch Just Before Collapse

Gaps Around Bay Window Glazing

Warning Signs of Bay Window Masonry Collapse

Rebuilding Bay Window Brick Arch

Rebuilding Collapsed Bay Brickwork

After Bay Window Rebuilding

Rebuild of Bay Window Brickwork

As is often the case, this property showed signs of previous failed attempts at repairing the defects using traditional building techniques. Re-pointing dropping and sagging brickwork provides only a temporary, cosmetic solution, it doesn’t repair the underlying structural issues.

The bay window brickwork required realignment, structural reinforcement and rebuilding all without compromising the original period features.

Temporary supports were installed to prevent further damage to the masonry. AWT’s specialist realigning cramping equipment was used to straighten the bowed brickwork.

The collapsed masonry was rebuilt with the original components where possible. Replacement bricks and mortar were colour matched. A steel spine was built into the columns during rebuilding to strengthen and restrain the brickwork.

AWT’s special diamond drilling methods were used to introduce stainless steel bed joint reinforcement to strengthen the brickwork and redistribute the weight of the brickwork above. Grouted anchor fixings, lateral restraints and resin bonded ties were also installed to reinstate the strength and uniformity of the wall. The chipped and cracked window cills were also repaired using Flexcrete.

The result was a restoration of not only the structural strength of the bay window but also the preservation of the period features.

AWT provide cost effective structural repairs for a wide range of structural issues including failing and collapsed bay windows. We operate not only in SW 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.

Repairs to Ornate Window Columns

Structural Repairs for Ornate Victorian Window Columns

l SW4 windows gaps - Repairs to Ornate Window Columns

l after SW4 column repaired - Repairs to Ornate Window Columns

l SW4 bay cracked 1 - Repairs to Ornate Window Columns

l after SW4 bay repairs - Repairs to Ornate Window Columns

l SW4 bay cracks - Repairs to Ornate Window Columns

l after SW4 bay repaired - Repairs to Ornate Window Columns

Structural Repairs for Ornate Period Windows

Before Window Structural Repairs

After Window Structural Repairs

Before Bay Window Structural Repairs

After Bay Window Structural Repairs

Before Bay Window Structural Repairs

After Bay Window Structural Repairs

The exterior of this 4 storey property in the London Borough of Lambeth, SW4, is packed with beautiful period features. As well as stone columns with ornate capitals, it also has decorative brick pillars and arched windows.

Sadly, a combination of ageing and ineffective restraining of the stone and brickwork columns was allowing the columns to bow out and the brick arches to drop and spread. This was cracking the surrounding brickwork. If the window columns, pillars and arches were not restrained and reinforced it would result in the failure of the window supports and the collapse of the structure above.

The Structural Problem

This period home in South West London, like many properties with serious structural defects, showed signs of previous attempts at repair by standard building methods. Repointing in areas where the brickwork columns had bowed failed to prevent the columns bowing further. Without specialist structural repairs the columns and arches would fail and cause the structure above to collapse.

As shown in the gallery below, AWT designed a programme of repairs that target the root cause of the structural failings. Due to AWT’s specialist equipment and know how, demolishing and rebuilding the affected areas was not required. AWT used precision drilling equipment to install fixings within the masonry, restoring structural integrity without damage to the period features.

Read our frequently asked questions about bay window structural repairs.

p bowing columns lambeth - Repairs to Ornate Window Columns

p SW4 window column repairs - Repairs to Ornate Window Columns

p column gaps lambeth - Repairs to Ornate Window Columns

p SW4 column repairs - Repairs to Ornate Window Columns

Before Window Column Realignment

Window Column Structural Repair

Gaps Around Windows

Realignment & Repair of Window Columns

The property had 3 areas that required structural repairs:

The 2 Storey Bay Window

Visible rotational bulging
Signs of distortion and distress with rotational movement
Dropping of brickwork arches
Leaning of the supporting columns
Cracks

Front 1st Floor Window

Significant outward movement to the first floor right hand stone column and capital
Unrestrained column had moved outwards allowing the attached brickwork to lean outward and drop
Resultant gaps between the timber window box frame and the column

Rear 2nd Floor Window

Significant outward bowing movement to the two brickwork columns
Unrestrained brick columns moved outwards leaving a bow shaped space between the timber window box frame and the column
Attached brickwork leaning outward

The Structural Repair Solution

p structural repairs lambeth 225x300 - Repairs to Ornate Window Columns

SW4 structural repairs 225x300 - Repairs to Ornate Window Columns

p SW4 structural repairs 225x300 - Repairs to Ornate Window Columns

AWT’s specialist repairs were designed to alleviate the masonry defects, add tensile strength and restore the integrity of the masonry without compromising the beauty of the period features.

Installation of custom fixings within the masonry redistributes the upper storey loads to those parts of the supporting structure below which are best able to carry them. This also restrains diagonal cracking and bulging of the brickwork.

Install temporary supports
Deploy AWT designed realigning cramping equipment
Use specialist hydraulic powered jacks to realign the columns and brickwork arches
Install steel corded bed joint reinforcement embedded within the masonry
Reconnect and reinforce the masonry by precision drilling and installation of Cintec sock anchors
Reconnect the bay window’s brickwork and masonry using grouted 8mm helical bars
Repair damaged stonework with Flexacrete
Replace cracked bricks and mortar ensuring suitable colour match

Action Wall Ties are specialist structural repair contractors with the skills required to reinforce and realign window support columns 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 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.

Remedial Wall Ties for Victorian Semi in Surrey

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.

Hazardous Masonry on Grade 2 Listed Building

Listed Building with Bulging & Cracking Masonry

This Grade II listed building in Thanet, Kent, was built in the 1840’s. The owners of this period property were facing the prospect of demolition and rebuilding of the facade of the property due to serious structural defects. Previous repairs using standard building techniques had failed to solve the structural problems. The property is currently in use as a nursery school. The business would have been forced to close for several months during traditional building works. AWT were able to repair the severe structural problems in a couple of weeks and preserve the period features without disrupting the running of the business.

The Structural Problem

The structural issues with this Victorian, Grade 2 listed property in Ramsgate, Kent were becoming hazardous due to the risk of falling masonry. Traditional building methods would have required several months of expensive and messy deconstruction and rebuilding work. The business would have been forced to close during the building works and the subsequent re-plastering and redecoration.

The front of the building had clearly visible bulging and cracking to the head of all the first floor windows. There were also cracks in the brickwork and stucco works each side and to the underside soffit of the window opening heads. There were clear signs of previous attempts at repairs that had failed to get to the root cause of the problems.

grade 2 listed structural defect - Hazardous Masonry on Grade 2 Listed Building — Buckling Brickwork

As shown in the photo below, the mild steel embedded within the masonry had corroded and the rust caused it to expand to several times the thickness of the original metal. The heavily corroded wrought iron arch bars were lifting and cracking the brickwork and the decorative stucco around the windows. The stucco stringer course frieze and cornice of the parapet wall was also cracking and distorting. Previous attempts at repairs had provided a temporary, cosmetic repair but had failed to solve the underlying structural defects.

The continued expansive corrosion of the wrought iron arch bars would, without remedial works, lead to the failure of the masonry and the risk of detached masonry falling from the building. Urgent structural repairs were required.

Rusting wall bars 300x225 - Hazardous Masonry on Grade 2 Listed Building

Rusted metal grade2 listed 300x225 - Hazardous Masonry on Grade 2 Listed Building

The Structural Repair Solution

Structural repairs to listed buildings need to be handled carefully to preserve the period features of the building. AWT have many years of experience working on listed properties. AWT can help the owners of listed buildings to navigate through the process of obtaining permission for repair works.

The specialist tools and techniques that AWT employ allow structural repairs to be made without the need for visible fixings. Using custom designed drilling and cutting tools, AWT can remove corroded metal fixings and embed new stainless steel fixings within the masonry.

In order to allow the business to remain open during the structural repair works, AWT arranged for the scaffolding to be erected at the weekend while the nursery was closed. The scaffolding was then double boarded and netted for safety. The AWT crew accessed the scaffolding from the side of the building allowing parents, children and staff to access the building as usual through the main entrance.

vertical wall ties 225x300 - Hazardous Masonry on Grade 2 Listed Building — Preparing Vertical Wall Ties

grade 2 listed structural works 225x300 - Hazardous Masonry on Grade 2 Listed Building — Drilling for Vertical Wall Ties

The AWT team used their specialist techniques to form composite beams within the existing brickwork and then remove and replace the corroded wrought iron arch bars. The team then reconnected and reinforced the brickwork above the windows and the parapet wall. They also repaired the cracked decorative stucco.

Before metal grade2 listed 225x300 - Hazardous Masonry on Grade 2 Listed Building — Before – Cracks & Broken Bricks

replacement lintel Thanet Kent 225x300 - Hazardous Masonry on Grade 2 Listed Building — During – Lintel Replaced

After metal grade2 listed 225x300 - Hazardous Masonry on Grade 2 Listed Building — After – Ready to Paint

This project required a combination of:

Bed joint reinforcement beaming
Grout tie injection
Resin bonded ties
Cintec sock anchors
Removal of corroded mild steel arch bars
Replacement arch bars
Brickwork repairs

The team at AWT strive to make all works as sympathetic as possible with the existing masonry. Not only do they try to match replacement bricks and pointing for colour and style they even match the mortar mixture texture.

The high quality fixings used by AWT combined with their thorough knowledge of structural defects ensures a long term solution to structural issues.

Action Wall Ties are structural repair contractors with the specialist skills required for listed buildings. AWT work along with property owners, architects, project managers and local authorities to preserve historic buildings.

AWT are available for large and small projects 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.

Stone Arch & Bay Window Reinforcement

Reinforcement and Repair of Ornate Stone Arch & Bay

This end of terrace home in Walthamstow, East London had 2 structural issues. The stone entrance arch had significant cracking to the brickwork above and cracking in the internal walls. The ornate bay window was dropping and leaning outwards plus the stonework was cracking and spalling.

The Structural Problem

The period decorative features on this home in London, E17, were showing their age due to structural issues causing cracked brickwork and stonework. The structural movement had exacerbated the deterioration of the paintwork leaving the beautiful, ornate stonework looking shabby.

There was significant cracking above the stone entrance arch in both the external brickwork and the internal walls.

The bay window had visibly shifted and caused cracks in the external brickwork as well as in the interior walls. The supporting columns and cills had become distorted.

These are common problems in such Victorian / Edwardian properties and are usually the result of ageing and inadequate restraining in the original building methods.

The AWT team also had to be prepared in case the masonry components weren’t solid masonry but simply a thin facade covering a timber frame.

Walthamstow brickwork repairs 230x120 - Stone Arch & Bay Window Reinforcement

Walthamstow stoneworkwork repairs 230x120 - Stone Arch & Bay Window Reinforcement

E17 stone repairs 230x120 - Stone Arch & Bay Window Reinforcement

The Structural Repair Solution

Installation of temporary supports & AWT designed cramping equipment
Realignment of masonry with hydraulic jacks
Precision diamond drilling & installation of stainless steel corded joint reinforcement.
Reconnecting the bay window brickwork to the main elevation by embedding grouted 8mm helical bars.
Installation of lateral restaints.
Repair damaged stonework with Flexcrete Monomix concrete repair mortar system.
Crack stitching work to cracked brickwork.
Cutting back damaged brick faces or resurfacing damaged bricks where possible using AWT methods.
Cutting out badly cracked bricks and replacing with colour matched yellow stock bricks.
Re-point disturbed areas with colour matched sand lime and cement mixture.

AWT provided an efficient, cost effective, permanent repair without the need for visible fixings. AWT have the tools and skills to remediate the root cause of these types of period property structural defects. AWT’s specialist fixings meant no rebuilding work was required and so disruption to the homeowner was kept to a minimum. The property was left ready for painting to restore it to its former glory.

Read our frequently asked questions about bay window structural repairs.

For a fast, effective solutions to stone arch and bay window structural problems contact AWT today. We provide professional solutions to a wide variety of structural issues for home owners across London, Kent, Surrey and Sussex. Contact us on 01227 721 255, or email us.

Repairing Gaps Around Bay Window Glazing and Distorted Gable Brickwork

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.

Read our frequently asked questions about bay window structural repairs.

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.

Bay Window with Severe Deterioration

The brickwork of this mid-terraced Victorian/Edwardian era home in the Stratford, E11 area of London had reached a critical condition. The severe nature of the building’s defects required a combination of specialist structural repair techniques.

The Structural Problem

Without urgent structural repairs, the bay window masonry of this period property would collapse. Symptoms of the severe masonry defects were:

Front bay windows visibly bowing outward
Severe deterioration of bricks in the bay window pillars
Crumbling, spalling bricks
Distorted cracked stonework
Cracking brickwork
Failing, spalled pointing
Cracked front entrance concrete step
Significant cracking and dropping of brick arch lintels

The problems had been caused by ageing, seasonal moisture, thermal expansion and contraction and inadequate restraining of the masonry due to the building methods of the era.

The Structural Repair Solution

Traditional building methods would have required major deconstruction and rebuilding works. AWTs advanced methods allowed the property to be repaired with only one brick pillar requiring rebuilding. This saved the property owner from long, disruptive building works. The property was able to be occupied throughout the repair works. AWT provided a long-lasting, cost-effective structural repair.

Temporary supports were installed to the underside of the ground floor bay window lintels and capital to enable the removal of the right hand column up to the stone capital and the cracked distorted brick corner below the cill.

Stainless steel corded joint reinforcements were installed to form a deep masonry beam. This redistributes the upper-storey loads and restrains diagonal cracking and bulging tendencies.

The bay window brickwork was reconnected to the main brickwork by the installation of remedial grouted helical bars. An angled steel spine reinforcing with welded ties to restrain the rebuilt brickwork column was fabricated and installed. The brickwork column was realigned and rebuilt with all new bricks.

New stainless steel remedial ties were screwed and resin bonded in place to connect the timber frame to the masonry. Steel pins were installed to stitch the brick arches above the rear windows to restore structural integrity.

The stone front step and other stonework had damaged areas cut away and repaired with Flexcrete concrete repair system. Damaged bricks were refaced where possible, badly damaged bricks were replaced and failing pointing was raked out and replaced.

The replacement bricks, pointing style and mortar mixture were matched for both texture and colour. The property was left ready for the stonework to be repainted.

Read our frequently asked questions about bay window structural repairs.

Action Wall Ties (AWT) are specialists in masonry reinforcement and repair, including urgent masonry stabilisation and repair. We provide professional solutions to a wide variety of structural problems for homeowners in London, Kent, Surrey and Sussex. Contact us on 01227 721 255, or email us.

Fixing Cracking Above Concrete Boot Lintels

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

Boot lintel gaps cracks rotation - Fixing Cracking Above Concrete Boot Lintels

Boot Lintel stepped cracks - Fixing Cracking Above Concrete Boot Lintels

Boot Lintel gaps - Fixing Cracking Above Concrete Boot Lintels

Boot Lintel compression - Fixing Cracking Above Concrete Boot Lintels

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.”

case 55 a - Fixing Cracking Above Concrete Boot Lintels

case 55 d - Fixing Cracking Above Concrete Boot Lintels

case 55 b - Fixing Cracking Above Concrete Boot Lintels

case 55 c - Fixing Cracking Above Concrete Boot Lintels

case 55 e - Fixing Cracking Above Concrete Boot Lintels

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.

Contact us on 01227 721 255, or email us.

Bowing brickwork on Victorian semi

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.

Victorian Crack Stitching and Lintel Repair

Victorian Property: Crack Stitching & Lintel Repair

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.

reconnect superstructure 10 230x120 - Victorian Crack Stitching and Lintel Repair

reconnect superstructure 8 230x120 - Victorian Crack Stitching and Lintel Repair

reconnect superstructure 13 230x120 - Victorian Crack Stitching and Lintel Repair

reconnect superstructure 12 230x120 - Victorian Crack Stitching and Lintel Repair

reconnect superstructure 6 230x120 - Victorian Crack Stitching and Lintel Repair

reconnect superstructure 7 230x120 - Victorian Crack Stitching and Lintel Repair

reconnect superstructure 4 230x120 - Victorian Crack Stitching and Lintel Repair

reconnect superstructure 3 230x120 - Victorian Crack Stitching and Lintel Repair

reconnect superstructure 1 230x120 - Victorian Crack Stitching and Lintel Repair

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.

Victorian bay window repairs c2 300x225 - Victorian Crack Stitching and Lintel Repair

Victorian bay window repairs c3 300x225 - Victorian Crack Stitching and Lintel Repair

Victorian bay window repairs c1 300x225 - Victorian Crack Stitching and Lintel Repair

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.