Masonry grouting is a process used to reintroduce structural integrity to solid single thickness walls comprising of natural stone facings such as flint, granite or sandstone with a random rubble internal core.
The original wall will generally have been constructed of a lime mortar to bind all of the elements together. Over period of time, particularly if a structure has moved and cracked the masonry water penetration can gradually leach fine particals from the lime matrix reducing its bonding capacity and ability to support the wall or loads imposed upon it.
Grouts can be a slurry mixture of lime, sand and water or a more thixotropic design mixture specific to the characteristics of the structure under repair. These can be used alone or with Grout Ties to provide more tensile strength within the matrix to withstand delamination of component parts of a wall.
Grouting requires a high degree of quality control
This is to ensure that the objectives of void filling and consolidation are achieved without damaging the structure through excessive grout pressure. We can repair this type of wall utilizing a low pressure hand operated pump system with either lime or cement based grouts and introduce wall ties at specified centres as work proceeds. This method minimizes hydrostatic pressure within a wall and hence disruption to the building and its occupants whilst work is in progress.
Pictures illustrating a Grout Tie system designed for strengthening a buttress on Blundeston Church in combination with an injected grout mix to fill voids.