Basement waterproofing on this project was a two part that included a combined-protection system to ensure the joint between old and new buildings is secure. Midland Tanking was the designer and installer for both systems.
Primary System (external)
Type B – Waterproof concrete integral protection
The new concrete walls was created by erecting temporary shuttering and steel work and then cast with concrete including a waterproof additive. The steel reinforcing within this structure was designed to reduce the cracking to less than 0.3mm, also providing integral protection.
Primary System (internal)
Type A – Barrier Protection
The existing and newly underpinned walls and floor were all coated with a two coat crystallising waterproofing slurry this provides most of the basement waterproofing protection
Secondary System
Type C – Drained cavity protection
With the primary waterproof concrete system providing most of the protection, the secondary system was installed. All walls and the floor were lined with a cavity drainage membrane (CDM). These membranes were linked to sump chambers via the a preformed perimeter channel. Within the sump is two pumps and a high-level alarm. This system is designed to catch any water that is not stopped by the primary system and discharge it automatically. Flushing and maintenance points were installed to allow future servicing of the system. The front and rear lower sections are linked with a underground pipe.
Both basement waterproofing systems were designed by Structural Surveyors in Structural Waterproofing (CSSW) in accordance with BS8102:2009
All waterproofing materials were supplied by Triton Systems Ltd
