Cracking Around a Bay Window, London
The Problem
We were recently contacted by a homeowner in New Malden, London who was concerned about cracking around a bay window.
There are several reasons that cracking around a bay window occurs, and this is often due to its original construction.
Bay windows were very popular in Georgian, Edwardian and Victorian houses, and building of the bay was often left until late on in the construction process so that the opening could be used for access. This was particularly the case with terraced properties.
Because the bay was often built late on, they were sometimes built on separate and less adequate foundations to the rest of the building. This can cause differential movement where the bay moves, but the rest of the building doesn’t.
This is particularly a problem in areas such as London, where the properties were built on clay soil. Clay soils are more vulnerable to subsidence because the soil shrinks when it is dry. Heave is also a problem because clay soils expand when they are wet.
The Solution
Fortunately, in this case, there were no signs of subsidence. However, cracking had occurred to the front bay projection where it had pulled away from the junctions of the main structure. This had caused cracking to occur in the walls, both externally and internally.
Our surveyor designed a specification for bed joint reinforcement to tie the bay back to the main structure, and to redistribute the structural loads. This was done using three twin bands of stainless-steel helical bar that are installed into the mortar joints between the upper at lower windows. The helibar wraps around the entire width of the bay, and is drilled back and resin bonded into the main structure, as per the manufacturer’s method statement.
Internally, the cracks around the bay window on the ground floor and the first floor were raked out, resin injected and made good.
Cracks in the walls were also spotted in the left gable elevation, the rear left flank elevation and internally in the hallway.
These were repaired using a combination of bed joint reinforcement, crack stitching and the installation of stainless-steel helical cem ties.
Project Completion
All areas of internal plasterwork were made good, and the homeowner was very pleased with the quality of work and the cost-effective solution that was provided.
Repair method used
The Problem We were recently contacted by a homeowner in New Malden, London who was concerned about cracking around a bay window. There are several reasons that cracking around a bay window occurs, and this is often due to its original construction. Bay windows were very popular in Georgian, Edwardian and Victorian houses, and building […]
