This Good Building Guide discusses one of the main challenges when designing a basement: preventing ingress of water or water vapour. The focus is on dampness due to penetration of groundwater, sometimes complicated by rising damp. This first part outlines the principles of constructing a waterproof basement. The second part describes the main methods for perimeter construction with advice on safety, insulation and services. Each part is 6 pages.

Contents of Part 1:

Site investigation
● Drainage characteristics of the soil
Site preparation and the control of moisture

Types of construction
● Type A: tanked protection
● Type B: structurally integral protection
● Type C: drained cavity

Waterproofing systems
● Bonded sheet membranes
● Cavity drain membranes
● Bentonite clay active membranes
● Liquid-applied membranes
● Mastic asphalt membranes
● Proprietary cementitious crystallization active systems
● Proprietary cementitious multi-coat renders, toppings and coatings
● Other waterproofing products
- Rubber or flexible waterstops
- Water-swellable waterstops
- Cementitious crystallization waterstops
- Post-injected waterstops

Subsurface drainage
References and further reading