Cavity Wall Tie Replacement:

Wall tie corrosion can lead to cracked external walls. We can provide a wide range of cavity wall inspections and repair solutions.

What is the purpose of cavity wall ties?


Cavity wall design, which uses metal wall ties to tie the inner and outer leaves together, has been in use since the beginning of the nineteenth century. The purpose of cavity walls is to prevent rain penetration and to improve thermal insulation.

Lateral Restraint – Bowed Walls

Wall tie corrosion can lead to cracked external walls. We can provide a wide range of cavity wall inspections and repair solutions.

Settlement and Foundation Issues

  • Normal Settlement: New buildings undergo slight settlement as the soil compresses under the weight of the structure. This can cause minor, typically non-structural cracks to appear.
  • Differential Settlement: Uneven settling of a foundation, often due to varying soil types or moisture levels, can cause more significant cracking.
  • Subsidence: Sinking of the ground beneath the foundation due to soil shrinkage, tree roots, or drainage problems. This can lead to severe structural damage and cracks.

Thermal and Moisture Changes

  • Expansion and Contraction: Seasonal temperature changes and moisture fluctuations cause building materials to expand and contract, potentially leading to cracks. This is especially true with brick and concrete materials.
  • Drying Shrinkage: Newly constructed homes or new plaster will shrink as excess moisture evaporates, often leading to hairline cracks.

Structural Issues

  • Improper Load Distribution: Structural flaws in the design, undersized beams, or removal of load-bearing walls can stress areas, causing cracks.
  • Roof Spreading: A lack of proper bracing in the roof can cause outward pressure on walls, leading to diagonal cracks above windows and doors.
  • Lintel Failure: Damaged or undersized lintels (supports above windows and doors) can sag, causing cracks in the surrounding masonry.

Other Factors

  • Tree Roots: Roots from large trees near foundations can absorb moisture from the soil, causing it to shrink and potentially leading to settlement issues.
  • Heavy Traffic: Vibrations from frequent heavy traffic can contribute to minor cracking, especially in older structures.
  • Infestations: Termite or other insect damage can weaken structural elements and lead to cracks.

Older Wall Ties (Pre-1980s)

  • Material: Wall ties constructed of mild steel were commonly used, and these have a much shorter lifespan.
  • Lifespan: Due to corrosion, these ties might need replacement within 15-20 years of the building’s construction.
  • Recommendation: If your house was built before the 1980s, it’s wise to have a specialist survey your wall ties, especially if cracks or bulges in the external
    walls appear.

 Modern Wall Ties (Post-1980s):

  • Material: Modern wall ties are primarily made of stainless steel, which is highly resistant to corrosion.
  • Lifespan: Stainless steel ties can last 50 years or more.
  • Recommendation: Replacement generally isn’t necessary unless there’s evidence of damage or failure.

Factors Affecting Lifespan:

  • Coastal Environments: Salt in the air accelerates corrosion, potentially shortening the lifespan of even stainless steel ties.
  • Quality of Installation: Poor installation practices can lead to premature failure.
  • Severe Weather: Extreme weather events or ground movement can put additional stress on wall ties.

1. Foundation Issues

  • Shallow Foundations: Bay windows were often added later in construction and may have shallower, separate foundations from the main house. This makes them prone to differential settlement.
  • Subsidence: Sinking of the ground due to shrinking soil (common in clay soil areas), drainage problems, or tree roots can cause the bay window to move independently, leading to cracks.

2. Structural Inadequacies

  • Insufficient Support: Historically, bay windows might have been built with less support than the main structure. The weight of the bay can cause it to sag over time, creating stress points and cracks.
  • Lintel Failure: The lintel (structural support) above the bay window opening might be damaged, undersized, or deteriorating, causing the masonry around it to crack.
  • Roof Spreading: If the roof lacks adequate bracing, it can exert outward pressure on walls, especially noticeable in a bay window area, causing cracks.

3. Thermal and Moisture Problems

  • Expansion and Contraction: Seasonal temperature changes and moisture variations can cause the building materials of the bay window to expand and contract, leading to cracking, especially in the joints and corners.
  • Water Ingress: Leaks in the roof or flashing around the bay window allow moisture to penetrate. This can cause deterioration, rusting of structural components, and localized movement, resulting in cracks.

4. Improper Installation

  • Poor Jointing: Inadequate or incorrect jointing techniques between the bay window and the main structure can create weak points where cracks are likely.
  • Replacement Windows: If new windows (especially uPVC) were installed without proper support or consideration of the bay window’s weight bearing, cracks are more likely.

ASRS use lateral restraint ties to connect the masonry to floor and/or ceiling joists, tying the two together. A hole is drilled into the masonry, level with the timber joists. The leading edge of the restraint tie is cut as a drill bit, as it is inserted, it cuts its way into two or more joists. The masonry end is then resin fixed, securely tying the masonry in. The hole in the masonry is then filled with colour-matched repair mortar to provide an invisible repair.

Other structural repair techniques such as crack stitching and bed joint reinforcement may also be required to repair cracks or to stabilise the masonry.

1. Crack Stitching & Resin Injection

  • Suitable for: Minor to moderate hairline cracks in concrete or brick lintels, often caused by thermal movement or minor settlement.
  • How it works: Metal rods (helical bars) are inserted along the crack. High-strength resin is injected, bonding the crack and restoring structural integrity.
  • Advantages: Minimal disruption, relatively cost-effective, and aesthetically pleasing.


2. Additional Support – Catnic Lintels

  • Suitable for: Lintels with more significant bowing or cracking, where the lintel itself is compromised but the surrounding masonry is stable.
  • How it works: A new steel lintel (often a Catnic lintel) is installed above the existing one to take over the load. The original lintel may be left in place or partially removed.
  • Advantages: Provides immediate support, suitable for wider cracks.


3. Full Lintel Replacement

  • Suitable for: Severely damaged, corroded, undersized, or poorly installed lintels.
  • How it works: Temporary supports (like Acrow props) are put in place. The existing lintel and surrounding masonry are removed. A new, appropriately sized lintel and brickwork are installed.
  • Advantages: Addresses the root cause, ensuring long-term stability.


4.Reinforcement with Steel Beams

  • Suitable for: Situations where significant additional loads are involved, or where there’s extensive damage to the lintel.
  • How it works: A steel beam (e.g., RSJ) is inserted above the lintel or within the wall to provide additional support. May involve opening up more of the wall for installation.
  • Advantages: Distributes heavy loads effectively, suitable for large openings and structural alterations.

A retaining wall is a structure designed to hold back soil or other materials, preventing them from sliding or eroding down a slope.

Unfortunately, there’s no simple answer to the question of how much a retaining wall costs. The price is influenced by a wide range of factors, including:

  • Size: Both the height and length of the wall directly impact the cost of materials and labor.
  • Materials: Common materials include:
  • Concrete blocks: Affordable and versatile.
  • Natural stone: More expensive, but aesthetically pleasing.
  • Timber sleepers: Budget-friendly, but less durable in the long term.
  • Gabion baskets: Wire baskets filled with stone, creating a unique look.
  • Complexity of Design: Curved walls, multi-tiered designs, or the presence of steps increase construction costs.
  • Site Conditions:
  • Ground condition: Soil type and stability affect excavation and foundation requirements.
  • Accessibility: Limited access for machinery can increase labour costs.
  • Drainage: Proper drainage systems behind the wall are crucial to prevent water pressure buildup and might add to the cost.
  • Location: Labour and material costs vary across regions.
  • Discover the best price for your retaining wall project. Get your customised quote now!

Masonry crack stitching is a structural repair technique used to stabilise and strengthen cracked walls made of brick, stone, or concrete blocks.

The method for repairing cracks in concrete depends on the type of crack and its severity. Here’s a breakdown of common techniques:

  • Hairline Cracks: Use a vinyl concrete patcher or patching compound.
  • Medium Cracks (up to 1/4 inch): Widen slightly, clean, and fill with concrete patch or repair caulk.
  • Large Cracks (over 1/4 inch): Widen, clean, apply bonding adhesive, and fill with patching compound.
  • Structural Cracks: Always consult a structural engineer for professional assessment and repair.

The cost of concrete repair varies widely depending on several factors:

  • Severity of Damage: Small cracks are cheaper to fix than large, structural issues.
  • Type of Repair: Simple patching is less expensive than resurfacing or foundation work.
  • Location of the Damage: Areas with difficult access or requiring special equipment will cost more.
  • Materials: Specialty concrete mixes or sealants can increase the price.
  • Labour: Professional contractors generally charge per hour or per square foot.
  • Region: Costs fluctuate based on your location.

Micropiling is a type of deep foundation technique used to provide structural support or underpin existing foundations. Here’s a breakdown of its key aspects:

What are Micropiles?

  • Small Diameter Piles: Typically 100-300mm in diameter, much smaller than traditional piles.
  • Materials: Usually reinforced steel or concrete.
  • Installation: Drilled or driven into the ground using specialized equipment.

Constructing pile foundations is a complex process that usually requires geotechnical engineers and specialist contractors. Here’s a simplified overview of the main methods and steps involved:

  1. Preparation
  • Site Investigation: Soil testing is crucial to determine soil type, load-bearing capacity, and groundwater levels, informing the pile type and design.
  • Pile Design: Engineers calculate pile dimensions, spacing, and reinforcement requirements based on the structure’s load and soil conditions.
  1. Types of Pile Installation
  • Driven Piles: Precast concrete, steel, or timber piles are forced into the ground using a piling hammer or vibrating equipment. Suitable for dense soils.
  • Bored Piles: A hole is drilled into the ground, a steel cage is inserted, and then the hole is filled with concrete. Good for various soil conditions and minimal vibration is required.
  • Augered Piles (CFA): A hollow-stemmed auger drills into the ground. Concrete is pumped through the auger as it’s extracted, forming a continuous pile. Versatile and efficient method.
  1. Installation Steps (Simplified)
  • Setting Out: Pile positions are accurately marked on the site.
  • Pile Installation: Using the chosen method (driven, bored, or augered). Equipment varies accordingly.
  • Cutting Off: Piles are cut to the designed level.
  • Pile Cap Construction: A reinforced concrete cap connects the tops of a group of piles, distributing the load from the structure.

Here’s why ASRS stands out:

Trusted & Authorised Installer for Renowned Systems:

  • Helifix Helibeam System
  • Cintec Anchor Systems
  • Fosroc Concrete Repair Techniques
  • Platipus Anchoring Systems
  • Chance Piling Solutions

 Proven Track Record:

Join prestigious clients like BMW, Johnson and Johnson, and the Ministry of Defence who have benefited from our services. Our success stories speak volumes.

+20 years of experience

Check the link: https://www.asrs.co.uk/about-us/

Here are the areas we offer our services:

  • Belper, England, United Kingdom
  • Gloucestershire, England, United Kingdom
  • Frome, England, United Kingdom
  • Midlands, England, United Kingdom
  • Somerset, England, United Kingdom
  • West Sussex, England, United Kingdom
  • Bloxham, England, United Kingdom
  • Surrey, England, United Kingdom
  • Clevedon, England, United Kingdom
  • Hampshire, England, United Kingdom
  • Odiham, England, United Kingdom
  • Hayling Island, England, United Kingdom
  • Swansea, Wales, United Kingdom
  • Didcot, England, United Kingdom
  • Taunton, England, United Kingdom
  • Birmingham, England, United Kingdom
  • Cwmbran, Wales, United Kingdom
  • Isle of Wight
  • Crewkerne, England, United Kingdom
  • Cardiff, Wales, United Kingdom
  • Bruton, England, United Kingdom
  • Loughborough, England, United Kingdom
  • Portsmouth, England, United Kingdom
  • Yate, Bristol
  • Buckinghamshire, England, United Kingdom
  • Willersey, England, United Kingdom
  • Devon, England, United Kingdom
  • Stratford-upon-Avon, England, United Kingdom
  • Newport, Wales, United Kingdom
  • Oxfordshire, England, United Kingdom
  • Wiltshire, England, United Kingdom
  • New Milton, England, United Kingdom
  • Dorset, England, United Kingdom
  • Bristol, England, United Kingdom
  • Redditch, England, United Kingdom
  • Berkshire, England, United Kingdom
  • Hertfordshire, England, United Kingdom