Waterproofing
Types and Durability
| Description
Basement Waterproofing | Expected Lifespan
( Years ) | Adjustment Factors |
| Preformed membrane
Sheet/ roll applied waterproofing with base materials to CP 82:1999, with method of fixing includes self adhesive, adhesive bonding, chemical welding, hot air welding, and mechanical fixing, in accordance to manufacturer instruction.
| 10 | Existance of aggresive ground water*: -15% years
Hydrostratic head** exceeding system design (except crystalline system): -10% years Test certificate from approved local testing authority: +15% years |
| Liquid applied system
Liquid (cold/ hot) applied with base material to CP 82: 1999, with method of fixing includes by means of squeegee, roller, brush, trowel or spray, in accordance to manufacturer instruction.
| 10 | |
| Liquid (cold/ hot) applied with base material not in accordance to CP 82: 1999, with method of fixing includes by means of squeegee, roller, brush, trowel or spray, in accordance to manufacturer instruction. | < 10 | |
| Integral system*
Integral waterproofing system with method of application includes by means of masonry brush or compressed air-spray equipment, or by dry shake or as admixture, in accordance to manufacturer instruction.
| 10+ |
In the case of 2 or more conditions of adjutsment factor occur, the percentage of year shall be added to obtain the durability value
Durability and adjustment factor quoted are set based on the assumption that the installation/ construction of waterproofing is according to manufacturer instruction or related standard.
The waterproofing system would require protection against sharp objects which could damage the system especially during back-filling.
* Ground water varies in agressiveness depending on the location and in some areas may consist of highly agressive conditions (due to the presence of sulphates and nitrates). Agressive ground water can also be found in areas of close proximity to the sea.
**Basement waterproofing are generally subjected to a high hydrostatic head with the groundwater exerting a considerable force onto the system. Depending on the system, some of the membrance are designed for 50 m head and some for 30m head, and some may be less than that.
Recommended Membrane Construction in relation to depth
| Water head (feet) | No. plies (fabric) | No. coatings (bitumen) | Bitumen*** |
| 0 | 2 | 3 | 60 to 75 |
| 1 to 3 | 2 or 3 | 3 or 4 | 60 to 75, 80 to 100 |
| 4 to 10 | 3 | 4 | 80 to 100 |
| 11 to 25 | 4 | 5 | 100 to 125 |
| 26 to 50 | 5 | 6 | 120 to 150 |
| > 50 | 5 or 6 | 6 or 7 | 120 to 150, 140 to 175 |
source: www.swrionline.org (Sealant, Waterproofing, & Restoration Institute)
*** for asphalt; multiply by 1.2 for coal tar