Composite drainboard for blindside application, and foundation assembly

A foundation assembly, comprising:

• a lagging layer adjacent to soil;
• a blindside drainage layer comprising:
• a drainboard with a patterned substrate core having an inward surface, and opposed outward facing surface, said outward facing surface connected to said lagging layer, said substrate core comprising a plurality of projections, forming concavities on said inward surface;
• a geotextile membrane attached to said substrate core and covering said outward facing surface;
• and
• a fiber membrane attached to said substrate core and covering said inward surface to provide a substantially smooth coating to said inward surface, wherein said fiber membrane absorbs a liquid waterproofing;
• a liquid-applied waterproofing layer, applied to said fiber membrane, and at least partially absorbed by said fiber membrane;
• and
• a poured concrete poured directly against said liquid-applied waterproofing layer wall having an outer face in contact with said liquid-applied waterproofing layer.

A method of forming a foundation, comprising:

• forming a lagging layer adjacent to soil;
• installing a plurality of composite drainboards on the lagging layer, each of said plurality of composite drainboards comprising:
• a patterned substrate core having an inward surface, and opposed outward facing surface, said substrate core comprising a plurality projections, forming concavities on said inward surfaces;
• a first geotextile membrane attached to said substrate core and covering said outward facing surface;
• and
• a second membrane attached to said substrate core and covering said inward facing surface and said concavities to provide a substantially smooth coating to said inward surface;
• applying liquid waterproofing to said second membrane to form a waterproofing layer;
• and
• pouring a concrete layer after applying said liquid waterproofing and in contact with said waterproofing layer to form a concrete wall.