Non-stop increases in urban land costs have led to more efficient use of space by building owners. This includes not only building upward, but also downward. Waterproofed plazas over occupied underground facilities and roof terraces became popular ways of maximizing both horizontal and vertical space.
All roofs eventually leak—it is just a matter of when and where. Nevertheless, the hope is that new roofing systems do not leak right from the start. It is critical to verify the watertightness of roofing, especially if it is to be covered with ballast or a vegetated roof assembly.
The primary purpose of below-grade waterproofing is not to keep water out of the basement, although that is an important consideration. Rather, its role is to protect the foundation and the entire building structure from the damaging effects of liquids and vapors.
Winners of the RCI 2016 Document Competition were recognized at the annual luncheon during the 31st RCI International convention and trade show in Orlando last month. The initiative honors members’ excellence in roofing, waterproofing, and exterior wall construction project documentation.
Over the 60 years I have been writing specifications, I have not read a single satisfactory suggestion as to how to deal with the thorny subject of “or equal” when it applies to below-grade waterproofing.