Blindside Waterproofing

What is Blindside Waterproofing?

Blindside waterproofing is different than what most people know as below-grade waterproofing.

Below-grade waterproofing is applied to poured foundation walls whereas blindside waterproofing is applied before the actual foundation is poured. Blindside waterproofing is done over a retention system and is something that should only be done by an expert.


When to use blindside waterproofing?

Blindside is often the best or only solution on projects where the property lines and or nearby structures limit any excavation or make access difficult for the more traditional methods of waterproofing. A common project may include “zero lot line” foundation walls or builds in a higher density located job-site.


The Video…

Phil Aitken from West Coast waterproofing talks about the process of Blindside Waterproofing.

West Coast Waterproofing Ltd operates across British Columbia and this specific project is being done in Courtney British Columbia on Vancouver Island.

 Blindside waterproofing was needed here as there would not be access to the back side of the wall once it’s poured. In order to waterproof the foundation, we will need to pre-apply the membrane before the concrete is poured, essentially waterproofing the substrate before it’s completed. In this example, you can see the shotcrete wall, retention wall done at the property line of the structure that is to be built. We then apply a layer of drainage mat to the shotcrete wall to allow any water to flow down to the internal drain system of the building. Next, we apply a membrane applied over the top of the drainage mat. The membrane is a proprietary product that is pressure-sensitive. Once the concrete gets poured against it fully bonds with the concrete and it will not allow lateral or vertical migration of water whatsoever.

The waterproofing system now being in place, the next step will be for the rebar crew to do their installation. Once the rebar is done a one-sided form will be built and concrete poured and the final wall will be completely waterproof.