Grouted ties Archives - Page 5 of 5

Cross Rail Projects Victorian Connaught Tunnel

Crossrail Projects Victorian Connaught Tunnel

AWT were the chosen contractors for the Crossrail project at the Victorian Connaught Tunnel in central London. Strengthening, pinning and pressure grouting techniques were used for this vital infrastructure project.

The Crossrail project was to breathe new life into the old Connaught Tunnel. It was built by the Victorians but was, at the time of this work, a disused brick-arched structure lying beneath London’s Royal Docks that survived a hit from a bomb during WW2. This was to be the only existing tunnel to be re-used for Crossrail. Works involved the widening, deepening, as well as strengthening, of the existing structure.

Action Wall Ties’ expertise and experience was sought to undertake the proposed strengthening works to the brickwork arches to the approach cutting, and the damaged area of brickwork rings that form the tunnel. This was to be carried out with the introduction of injected grout, grouted ties and pressure grouting areas where the brick work rings had separated, which was believed to be due to bomb damage.

In line with the Crossrail specification to reconnect the brickwork with the temporary supports in place we firstly drilled vertically 20mm holes 1000mm deep and injected cementitious grout, filling any contiguous voids. Once this was set we revisited the grout filled holes and re-drilled to 25mm for, and injected, cementitious grout and 16mm stainless steel bars simultaneously pinning the brickwork rings together.

After the completion of the pinning, in an attempt to fill any voids to complete the reconnection, we drilled a pattern of 16mm holes with the entrance counter drilled to receive injection packers, ready for the pressure grouting injection. With the pre-batched TamCrete MFC grout mixed and holes flushed with water we injected the grout up to 1 bar over injection pressure, until either hydraulic lock or venting grout from adjacent holes is attained.

Finally, AWT made good the entrance holes with concrete repair mortar.

AWT can provide cost effective structural repairs for a wide range of public sector and infrastructure projects. We operate not only in London but across the whole of the South East of England. We have many years of experience working on large projects, liaising with structural engineers and local authorities.

Contact AWT today to book a survey with one of our experienced team of structural repair specialists. Contact us on 01227 721 255, or email us.

Realigning Masonry on Victorian Bay Windows

Large cracks were clearly visible in the brickwork around the bay windows of this Victorian period property in South, London. Cracked bricks and dropping brickwork arches above the windows signalled the need for specialist structural repair work.

Bay Window Problems

Common problems with Victorian era bay window properties are dropping and sagging of the brick arches and cracked masonry. Insufficient structural strength allows the bay wall to lean away from the main building.

This Victorian period property in South London had clearly visible structural defects. Specialist structural repairs were necessary to save the decorative Victorian brickwork from eventual collapse.

Expert Bay Window Repairs

Realigning cramping equipment specially developed by AWT was used to support the defective brickwork. Hydraulic rams were then employed to gradually realign the distorted masonry, using our tried and trusted methods, developed over many years working with bay window defects.

The remedial work to the dropping and sagging brickwork included:

Installation of stainless steel corded joint reinforcement
Use of AWT bespoke drilling rig with diamond tipped drills
Installation of stainless steel pins to reinforce the window lintels

When the repointing had been completed the beauty of the original Victorian brickwork could be fully appreciated once more.

The innovative structural repair techniques developed by AWT preserved the original facade without the need for demolition and rebuilding. The end result was a cost effective, long term solution to the problem that preserved the period features of the property.

Action Wall Ties offer structural repair services for period properties for clients in the South East, London, Kent & Surrey

Action Wall Ties (AWT) are specialists in bay window repairs to period properties with bespoke solutions including steel corded joint reinforcement. We also offer professional solutions to a wide variety of other structural issues. Contact us on 01227 721 255, or email us.

Unstable Masonry on Victorian/Edwardian Bay Window

AWT was called in after replacement bay windows had been fitted to this period property in London SE15. Cracks had appeared in the surrounding masonry plus outward movement of the two storey bay window’s supporting masonry column, lintel and brickwork.

A temporary support had been put in place but urgent action was required to restore structural integrity.

Collapsing Bay Window

What started out as a simple home improvement revealed structural issues with this Victorian/Edwardian period property in Lewisham, SE London. The masonry of the 2 storey bay window had become unstable and was being supported with a temporary prop. AWT were able to realign and reinforce the structure without the need to demolish and rebuild the brickwork.

Specialist Bay Window Repairs

AWT have designed and developed specialist realigning cramping equipment. This provides a stable framework that then allows careful use of hydraulic rams to realign the distorted brickwork. The brickwork arches, columns and masonry elements were returned to the level of the adjacent brickwork and joints were closed up again.

Custom made, stainless steel reinforcing restraints were introduced into the brickwork, leaving no visible support. This is an important consideration, especially for period properties.

Attention to Detail

AWT’s specialist structural repair skills saved the ornate stucco rendered brickwork around the windows from being destroyed. AWT’s attention to detail includes matching not only the colour but also the texture of the original mortar when repointing the disturbed areas. When the stucco render was painted the whole area looked as good as new.

AWT’s structural repairs are quicker and more cost effective than using a general builder. AWT are able to get to the root cause of bay window structural issues and provide a long term solution.

AWT provide help for owners of period properties across the South East – Greater London, Surrey, Kent, Sussex and Essex.

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.

Unstable Bay Window

Bay Window Cracking & Sagging After Installing New UPVC Windows

The bay windows in this London, SW2, property had become unstable due to the removal of the original timber windows for replacement double glazing installation. Problems were manifested as cracks in the plaster and brickwork. Gaps also opened up between the ceiling and the bay wall.

AWT was able to restore structural integrity to the bay window without the need for slow, costly rebuilding work. AWT provided a cost effective, long term repair with minimal disruption to the ongoing restoration project.

case study 5b62dbe93c42d4.63894392 - Unstable Bay Window — Gaps, cracks & damaged brickwork. Structural issues caused by replacing windows in period bay windows.

Common symptoms of structural issues arising from fitting replacement windows into bay windows include:

Cracks in internal walls around bay window
Gaps opening up between the ceiling and the bay window wall
Difficulty opening/closing windows
Cracks in external brickwork
Bay window masonry sagging
Bay window masonry leaning/pulling away from the main elevation

The Structural Problem with the Bay Window

During the refurbishment of this mid-terraced Victorian/Edwardian period property in Brixton, South West London it became evident that there was a serious structural issue with the bay windows. Cracks were radiating out from the bay window brickwork and the first floor bay window was leaning outward. Both the plaster and the brickwork showed significant cracking.

The Action Wall Ties team quickly discerned that when UPVC windows had previously replaced the original timber sash window frames the supports afforded at the head of the bay had been removed. This had allowed the bay window to sag, drop and rotate away from the main elevational house wall.

Initially, temporary supports were put in place to the underside of the first floor front bay window masonry. This prevented further deterioration of the brickwork.

This is a common problem that AWT is called to repair. Removal of timber sash windows from a bay window often leaves the bay window brickwork without sufficient support. Structural problems with the bay window masonry may become evident during or after the fitting of new double glazed units to the bay window.

Restoring Structural Integrity to the Bay Window

Action Wall Ties’ plan involved restoring the structural strength integrity of the bay window and redistributing the load from the upper storey of the property.

Utilising our specially developed equipment, tooling, methods and skilled staff allowed the realignment of the leaning masonry. This was followed by the fabrication and installation of remedial steelwork and fixings. The introduction of bed joint reinforcement beaming, to form composite beams within the masonry, together with lateral restraints restored the structural strength, all with minimal impact on the face of the brickwork.

Action Wall Ties used bed joint reinforcement beaming, lateral restraints and grout tie injection to reinforce the masonry. Steel lintels and columns were also fitted.

Replacement bricks were colour matched to blend with the original masonry. The pointing style and mortar mixture were also designed to match the original texture and colour.

Action Wall Ties serve customers in SW London and throughout the South East i.e. in Kent, Greater London, Sussex, Essex and Surrey. We are often called in by homeowners encountering bay window problems following the fitting of new double glazed windows. We are experts in repairing and stabilising bay window brickwork and stonework.

Action Wall Ties (AWT) are specialists in masonry reinforcement and repair, providing professional solutions to a wide variety of structural problems including issues with bay windows. Contact us on 01227 721 255, email us or use our contact form.

Harrow High School. Corroded Window Arch Bars

Harrow High School. Corroded Window Arch Bars.

As can be seen in the photos, there were cracks in both the external brickwork and the internal plaster work around the windows of these school buildings in Harrow, Greater London. In places the external brickwork was crumbling.

The Structural Problem

The brickwork above the windows was visibly lifting and cracking. An inspection by Action Wall Ties quickly identified the cause as corroding mild steel arch bars which were reducing the support from the existing lintel arrangement. This type of fault also results in difficulties with opening and closing windows.

The flat brickwork arches in the building were of differing ages but all were built on mild steel arch bars. As these bars had rusted the resulting ferrous oxide (rust) expanded to several times the thickness of the original metal in turn lifting and cracking the brickwork above. In places the facing brickwork had crumbled to reveal the metalwork.

The Structural Repair Solution

The remedial works were designed to add tensile strength and reinstate the brickwork’s integrity without detracting from the appearance of the building.

The brickwork openings required remedial support and the arch bars needed to be removed to stop any further damage to the building. Bed joint reinforcement and beaming fenestration lintel repair techniques were used to restore the tensile strength of the masonry.

Bricks were carefully removed to allow the cutting and removal of the corroding arch bars. Two rows of twin 8mm stainless steel corded joint reinforcement fixings were installed forming a deep masonry beam. The formation of continuous beams within the existing masonry redistributes the upper storey loads and assists in restraining diagonal cracking and bulging.

Specialist drilling rigs were used to drill for and install helical stainless steel pins through the brick arch and into the line of the deep masonry beam that had been installed within the existing masonry.

Where possible the existing bricks were reused. Replacement bricks were colour matched to blend in with the original brickwork. The cracked mortar was raked out and repaired with new coloured sand and cement mortar to match the existing mortar.

Action Wall Ties serve customers not only in the Harrow area but throughout the South East i.e. Kent, Greater London, Sussex, Surrey and Essex.

Action Wall Ties (AWT) are specialists in masonry reinforcement and repair, providing professional solutions to a wide variety of structural problems including issues with window arches. Contact us on 01227 721 255, use our contact form or email us.

Rendered Victorian Terrace with Bulging and Sagging Brickwork

Victorian Terrace with Bulging and Dropping Brickwork

This Victorian terraced home with rendered brickwork in Walthamstow, East London was suffering with dropping and outward bowing of the brickwork.

The Problem

This rendered Victorian terrace home in Walthamstow, London E17, was suffering with significant distortion of the masonry. It also had dropping and outward bowing movement of the brickwork on the upper floor.

The left hand side external brickwork had bulged outward from the centre first floor. Internal movement to the junction of the dividing wall and external wall was also noted.

If structural repairs are sought early enough, AWTs specialist repair techniques may allow for repairs without removing render/pebble dash finishes. However, due to the advanced structural issues with this property, it was necessary to remove the render.

The Solution

The first step, after the initial survey, was to carefully remove the render finish on the front elevation to expose the underlying brickwork. As well as giving access to the brickwork this also allowed for a secondary survey to ensure there were no further issues with the masonry.

Our remedial work included:

Bed Joint Reinforcement Beaming
Crack Stitching
Fenestration Lintel Repair
Lateral Restraints
Grout Tie Injection
Brickwork Repairs
Realignment and Pinning of the Coping Stones

The repair work was designed to reinstate the uniformity of the walls and provide restraint in order to restore the tensile strength of the brickwork. It was also necessary to reconnect the main elevational brickwork to the brick internal dividing and party walls.

Action Wall Ties used specialist drilling rigs that enable precision drilling. State-of-the-art stainless steel fixings were then installed within the framework of the building. These techniques have been designed to deal with the root cause of structural faults rather than just provide a short-term cosmetic fix.

Carefully matched coloured sand and cement mortar was used to make good the drill holes. As can be seen in the photo, there are no visible fixings once repair works are complete. The exposed brickwork is left clean, tidy and ready for repointing. The facade of the house can either be left as exposed brick or the render can be replaced if desired.

AWT’s specialist skills allowed these serious structural faults to be repaired quickly and economically. No long and costly rebuilding work was required.

Action Wall Ties (AWT) are specialists in masonry reinforcement and repair. 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 problems for home owners in East London as well as the rest of London, Kent, Surrey and Sussex. Contact us on 01227 721 255, email us or use our contact form.

Failing Bressummer Lintel Due to Brown Rot

This Victorian/Edwardian terraced property with a render finish in South East London was suffering from advanced brown rot in the wooden bay window lintel and floor joists.

The Structural Problem

Brown Rot had taken hold in the horizontal load bearing timber beam in the front bay window of this home in the Hither Green, SE13 area of London. The rot had also spread to the adjacent cantilevered floor joists.

The beam and joists were no longer strong enough to support the weight of the building. The bay window area of the property was becoming unstable. The brickwork was cracking and bulging.

If structural repairs are sought early enough or if the structural defect is localised, as in this case, AWTs specialist repair techniques may allow for repairs without removing the render. The small disturbed areas of render can then be made good with a concrete repair mortar system.

The Structural Repair Solution

Action Wall Ties acted quickly to firstly stabilise the structure to prevent further movement.

Before installing temporary supports and starting to uncover the Bressummer beam AWT installed Bed Joint Reinforcement Beaming both externally and internally. Box beams were also installed.

Bed Joint Reinforcement Beaming requires precision drilling and injection of stainless steel bars and Cementitious grout into the brickwork. No fixings are visible once the work is complete. Re-pointing with colour matched sand and cement mortar gives a neat finish.

This vital work redistributed the upper storey loads to those parts of the supporting structure which were best able to carry them. It also assisted in restraining any further diagonal cracking and bulging of the brickwork.

When the temporary supports were in place the bay window beam and rotten floor joist were replaced. With the structural integrity restored, this property can now continue to be a home for many years to come.

AWT can provide cost-effective structural repairs for a wide range of structural faults including rotting wooden beams. AWT can advise on structural repairs to properties with render, pebble dash and spar dash finishes. We operate not only in SE 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, call us today on 01227 721255, email us at enquiries@actionwallties.co.uk or use our contact form to get in touch.