Waterproofing: A Tale of Two Roofs

Contributor: Swinerton Blogger   |   February 07, 2017   |   Image Gallery »
Waterproofing: A Tale of Two Roofs

Our client had the opportunity to evaluate and implement two different roofing systems on their campus buildings.

These two projects used two different types of roofing materials and were located in the same vicinity, which made it more difficult due to the space restrictions involved in working simultaneously. One roofing system used Sika Sarnifal, the 80 mil single ply sheet. Another system used Kemper Roofing System for the deck-waterproofing project of the colonnade structures.

There are a few significant differences between Sika and Kemper. Sika’s Sarnafil PVC Roofing Membrane does not require factory-certified labor. Any roofer with minimal training will be able to install the PVC roofing. In contrast, Kemper Roofing system requires the supervision of Kemper-certified senior supervisor on site and Kemper-trained SBS foreman and workers to perform the installation. An installation process that does not adhere to Kemper’s protocols will void the product warranty. Kemper installation also is more sensitive to weather/environment conditions. Ideally, Kemper product is to be installed on a clear, sunny day due to its strict installation restrictions. The weather condition was an issue that affected this project where a delay period of over one week was needed.

The utilization of work area was also different between these two projects. The contractor that used the Sika system required that the staging area for the roofing materials to be in close proximity to the targeted building throughout the duration of the project. A temporary tower was erected for workers’ access to the roof of Building 14. Foot traffic access as well as parking area had to be managed on a daily basis so that there was no interruption to both daily campus activities in the area and the proposed construction. 

In contrast, with the deck waterproofing project, the preparations of the staging area and mobilization were not an issue. The main issue was removing the existing roof element and/or the adhesive material down to the bare concrete deck per the requirement of Kemper product installation. This was a meticulous and time-consuming step. If these strict procedures were not met, there was a potential that the Kemper factory warranty could be voided.