External Areas - General Principles

Failure of waterproofing to external works such as decks, balconies, terraces and the various forms and locations of plant rooms is a significant defect that causes considerable (and commonly unrecoverable) costs due to the large numbers of these areas in the buildings we construct and the consequential damage caused as a result of leaks in these areas (services, finishes and equipment).

This has a very negative impact on our reputation and must be avoided. The end owners/users of our buildings do not pay for; or count on having leaks. The impact can range from is an inconvenience at the least, right through to considerable disruption and damage to affected business or residence.

The impact on us is potentially considerable - the subcontractor has usually either gone broke; ignores the issue; cannot be charged the real costs for rectification because there is insufficient retention held; or the issue arises outside of the defects period and there is no retention; or there is a number of excuses why it is not their problem – and so on. Either way time and time again, we are left wearing the costs and loss of productivity having resources on these time consuming rectifications.

To avoid this, a thorough understanding of what is required to provide an acceptable solution for each application and being uncompromising in relation to the control of these works. We cannot simply rely on what the architect or subcontractor advises us. Specifications are typically NOT “consistent” with our expectations, good practice or the relevant standards, because they are pieced together and do not address the fundamental principles for external area waterproofing.

To understand the requirements for the proper construction of external areas the policy is broken into 4 sections;

1. Fundamental waterproofing principles of all areas including preparation
2. Product Selection for different applications and finishes
3. Design approach for the different external areas and key ‘area specific’ requirements
4. Other aspects for consideration

Two layer torch on membrane to a podium