Structural Repairs for Bay Window with Ornate Terracotta Blocks
The exterior of this Victorian/Edwardian property in the London Borough of Lewisham, SW13, has a number of beautiful period features. The ground floor bay window columns have ornate capitals, the bay window brickwork includes terracotta blocks below the 1st floor bay and the roofline has decorative terracotta blockwork below the eaves.
In common with many properties of this age, a combination of ageing and ineffective restraining of the bay window columns, together with de-bonding of the main elevational brickwork, was allowing the bay window to lean outward. This was also opening up large cracks in the surrounding brickwork. Without structural repairs to restrain and reinforce the masonry, it will fail and lead to the collapse of the structure above.
Read our frequently asked questions about bay window structural repairs.
The Structural Problem
This period home in Inner London was at risk of structural collapse. Protecting the fragile terracotta blocks and eave brackets was a key consideration in designing the structural repair plan.
Some of the structural problems included:
- Large cracks around the bay window
- Clearly visible outward leaning of the first floor bay window masonry columns and lintels
- Significant outward movement of the masonry lintel to the left side main elevational wall
- Significant movement of all the terracotta ornate blocks below the soffits
- Fragile, period terracotta blocks & knee braces (eave brackets) required delicate handling
AWT’s repairs were designed to target the root cause of the structural failings. Due to AWT’s specialist knowledge and equipment, demolishing and rebuilding the bay window was not required. AWT used bespoke drilling jigs to install fixings within the masonry to restore structural integrity without damage to the period features, especially the fragile terracotta blocks.
The Structural Repair Solution
AWT’s specialist structural repair tools allow the masonry to be gently moved back to its correct alignment. As shown in the photo below, custom-made drilling equipment allows the installation of fixings within the masonry with minimal impact on the facade of the property. This redistributes the upper-storey loads and restrains the brickwork to prevent cracking and bulging. AWT’s specialist repairs were designed to realign and restore the masonry without damaging or replacing the fragile terracotta blocks.
The first step was to bring the masonry back in line by:
- Installation of temporary supports
- Intrusive inspection of masonry components that appear to be of solid masonry sections but could be nominal thickness components backed with timber framework, amending repair plan as necessary
- Careful removal of dislodged ornate terracotta blockwork and knees (aka knee braces or eave brackets)
- Set up AWT designed realigning cramping equipment
- Deployment of specialist hydraulic jacks to realign the bay window masonry and elevational brickwork
The structure of the property was then strengthened by the installation of high quality specialist fixings:
- Long diamond drilled grouted ties
- Lateral restraints
- Grout injection ties
- Resin bonded ties
Finally, the finishing touches were added to restore the period beauty of the property:
- Reinstate the terracotta ornate blockwork
- Repair masonry pillars and cills with Monolevel FC anti-carbonation cosmetic grade mortar
- Replace cracked bricks and mortar ensuring a suitable colour match
The repaired masonry elements were left ready for repainting. No external fixings were required – leaving the period features of the property to be enjoyed for years to come.
Action Wall Ties are specialist structural repair contractors with the skills required to realign and strengthen leaning bay window masonry including period and heritage properties with fragile or ornate features of brickwork, terracotta stone/masonry elements and plaster stucco works. AWT work along with property owners, architects, project managers and local authorities on large and small projects.