Treatment of Rising Damp
Walls of a solid brick construction are damp coursed by drilling a series of holes into the row of bricks at floor level and injecting a polysiloxane solution, under pressure, into the porous bricks. This is the level at which a damp course would be installed in new construction. The damp coursing solution, which is spirit based, readily permeates the brick work and surrounding mortar, and when cured, forms a board band of water proof masonry which extends below floor level.
To inject the damp coursing solution into the walls, a nozzle with an expanding tip is inserted into the hole. The solution is pumped in at pressures from 10 – 40psi, the solution can be readily seen permeating the brick work. With this method, there is no magic as with some of the other offered systems. You can easily see the product permeate the wall and create a broad band of water proof brickwork. In old buildings, the soft lime/sand mortar has furrows and gaps which leads to wastage and difficulty impregnating.
In newer buildings, the mortar is usually a stronger sand/cement mix and bricks have hollows and are more brittle. Impregnating into the mortar joint is then the more practical method. This is also more appropriate for external feature walls in brick veneer buildings to avoid and damage to bricks.
Where a wall is made up of more than one layer of brick work, each layer is treated in stages.
See the Code of Practice (Adobe PDF File) for more information.