Draining is one of the key causes of retaining wall failure, so it’s absolutely critical to get it right. Done correctly by a licensed and experienced retaining wall specialist, the retaining wall will last a lifetime.
However, it’s not a one size fits all process and is primarily dependent on the type of material used.
Retaining wall drainage for concrete besser block filled walls
Typically used for walls over 1.2m, concrete besser blocks require a number of steps for for proper drainage set-up.
An agg line is installed at the base of the retaining wall on the footing. Also that agg line needs to disperse either into the storm water or into an appropriate area. The back of the retaining wall should be waterproofed with at least two coats. Once dried, the back of the wall should be filled with gravel to draw the water down to the agg pipe and out.
As the blocks are laid, horizontal and vertical steel is installed for strength. The blocks are then entirely filled with concrete core fill.
Retaining wall drainage for a dry stack system
Conclusion
Another option is a dry stack system. If we build retaining walls with Tasman or Heron blocks this is a different method to a concrete filled block wall.
A retaining wall built with a dry stack system, means there is no mortar between the joints allowing for free drainage of the entire wall.
Tasman and Heron blocks are filled with gravel, not concrete for strength, this also allows for water to free flow through the blocks and out.
The back of the wall will also be filled with gravel for the same purpose.
An advantage to using Tasman and Heron blocks is they don’t need to be waterproofed. . Because these blocks are free draining any water can flow through and out with ease, this also means they dry out very quick after rain periods, eliminating water pressure build up resulting in longevity.
Tasman and Heron blocks also look fantastic and once finished and are maintenance free.
Drainage is one of the most important factors when it comes to building retaining walls. All our tradesmen know this, and it is a top priority for every trade involved, from start to finish on all our projects.
