Stratham, NH
Roofing Material Evaluation
Scope/Solutions
Thermoplastic polyolefin (TPO) membranes are widely used as single‑ply membrane systems on low-slope roofs and rely on thermal welds to create a watertight assembly. The effectiveness of the welded seam relies on proper techniques and the weldability of the membrane. SGH evaluated TPO roofing membranes from different manufacturing lots to determine why the welds in the older membranes were not performing as well as the newer products.
SGH conducted a study to asses the physical, chemical, and thermal properties of the TPO membranes. Highlights of our work include:
- Conducting physical testing in our laboratory to compare the peel strength of welds prepared in a laboratory setting to establish whether poor weld performance is due to welding technique or membrane weldability
- Taking microscopic measurements of the TPO membranes to establish whether membrane thickness falls within accepted standards, as this property is known to affect membrane performance
- Performing chemical analyses and thermal tests to evaluate differences in polymer and additive composition between the different manufacturing lots
We determined the samples from the newer lots contained more antioxidant protection, which affects membrane stability at the high temperatures required for thermal welding and underscores the importance of protecting TPO membranes from the elements prior to installation.
Project Summary
Key team members
