NCC Version:
2019 Volume 2 – Amendment 1
Area of NCC Requirements:
Part 2.2: Damp and Weatherproofing
- P2.2.1 – Rainwater Management
- P2.2.2 – Weatherproofing
- P2.2.3 – Rising Damp
Problem:
The construction project involves building external walls below the natural ground level. The National Construction Code (NCC) 2019 Volume 2 Amendment 1 does not provide Deemed-to-Satisfy (DTS) provisions for waterproofing such below-ground external walls.
There is also a need to address the lack of 150mm slab edge exposure, which would otherwise be required for compliance.
Solution:
A Performance Solution was developed to meet NCC 2019 Volume 2 Amendment 1 requirements for below-ground walls, referencing British Standard BS8102:2022. The solution incorporates core-filled blockwork with Xypex additive, MAPEI waterproofing systems (Planitop mortars, Plastimul or Mapelastic Smart membranes), and a Polyfond Kit Drain system for protection and drainage, supported by an under-slab polyethylene membrane. This approach ensures a Grade 3 watertight environment with no water ingress or dampness, satisfying the NCC Performance Requirements P2.2.1, P2.2.2, and P2.2.3.
Finalised Report:
The proposed waterproofing system, designed in accordance with British Standard BS8102:2022, successfully meets the NCC 2019 Volume 2 Amendment 1 Performance Requirements for rainwater management, weatherproofing, and rising damp. Expert evaluation confirmed that the system will provide a dry and durable below-ground environment, making the Performance Solution fully compliant and suitable for the project.