Roof waterproofing and UV protection renewal for PUR roof spray foam

Roof waterproofing with liquid plastic Purelastik

For old foam = PUR roof spray foam, regular UV protection renewal is mandatory. When the old UV protection has weathered, the rigid foam is attacked and becomes open-cell. This allows it to absorb moisture. Purelastik has proven to be a very good long-term protection.

Roof waterproofing for rigid polyurethane foam

Rigid polyurethane foam is not UV-stable. In terms of roof renovation using the in-situ foaming method, this means that the foam surface must be sealed with suitable UV protection. Today, foam roofs are provided with a long-term protection: PURelastik from ISOPOL. This type of coating makes a foamed roof largely maintenance-free. In the past, roof paints of various grades were used for UV protection. But they all had the same problem: they had to be renewed at certain short intervals.

Unfortunately, it was often the case that care and maintenance were neglected. Because the foamed roofs were still tight for many years despite the lack of UV protection, no one noticed this defect. Due to changes in personnel or ownership, there were no longer any contact persons in many companies who were familiar with the roof problem. The photos on this page show the condition before and after the renovation. No roof maintenance on these roofs is bad. Incorrect maintenance, however, is even worse. While a roof without UV protection will remain tight for many years (about 0.2 mm of foam weathers off per year), incorrect recoating materials cause significant secondary damage.

PURelastik offers optimum long-term protection for all foamed roofs.

PURelastik forms a very good bond with the substrate, whereby the degree of weathering is almost irrelevant. PURelastik is sufficiently breathable and is also suitable for surfaces with standing water!

In addition, PURelastik provides a reliable improvement in mechanical load-bearing capacity. PURelastik forms a highly elastic, plasticizer-free film with excellent elongation at break, is seamless and jointless on the roof, and can even be applied to damp foam roofs (in full reinforcement).

In the event of greater moisture penetration, PURelastik ensures that the soaked foam dries out again by diffusion and with the aid of special expansion ventilators over a longer period of time!

Liquid plastic on old foam

Liquid plastic on old foam offers a long-term solution for both old, weathered foam roofs and newly foamed roofs. In the early days of roof renovations with rigid PUR foam, the UV protection had to be renewed every three to five years. This is no longer the case today. Modern liquid plastics, and Purelastik is one of them, have service lives of up to 25 years. Provided that the plastic is processed according to specifications. The bstaatl. Materialprüfamt MPA-NRW in Dortmund has successfully tested Purelastik for approval according to W3S. You can view the test results in the download area.