Architectural design uses retaining walls not only as a visual element but also to provide structural integrity to a landscape. When contained within robust retaining walls, steeply sloped masses of land can be put to good use, creating a balance between the wall’s vertical forces and the lateral forces of the soil above the retaining wall’s footings. In the absence of a retaining wall, this balance is disturbed when external influences such as rain are placed on the wall.
When water accumulates within the side of the wall, it can place stress on the structural integrity of the wall, leading to collapse. This can happen after excessive rain for instance, when the collected water increases the hydrostatic pressure. If the overturning movement caused by the increased pressure is more than the resisting vertical forces of the wall, the wall will collapse.
To mitigate this eventuality, retaining walls are built with appropriate drainage systems. Water can be prevented from building up against the side of a wall, and causing the wall to become unstable. There are several forms of drainage that can be installed into a retaining wall.
Weep holes
Weep holes are small openings that allow water to drain from within an assembly. Located at the bottom of the object, they allow for water to escape from within the wall; the weep hole must be sized adequately to overcome surface tension.
Drainage pipes
Perforated drainage pipes can be placed behind a wall to allow water to enter along the length of the wall. With the water escaping through the pipe, the hydrostatic pressure behind the wall is reduced.
Permeable or granular material
Drainage aggregate or larger rocks placed on the soil will allow water to penetrate deep into the ground. Instead of getting trapped, water has the required space to move through the soil and reach weep holes and drainage pipes.
An incline in the landscape
An incline in the landscape leading away from the wall can help prevent water from building up at the bottom of the wall, making it unstable and ready for imminent collapse.
Baines Masonry’s Wall Drain Pro
The Wall Drain Pro is a supplementary product from Baines Masonry Blocks designed for construction projects to effectively remove collected water around retaining walls. The Wall Drain Pro resolves the water drainage issue associated with retaining walls in a visually pleasing way.
Key benefits include easy installation; drain height easily modified for use with any size block; integral component of wall construction; and multiple colour options to match the block.
