Water-repelling plywood suitable for humid conditions in construction

By | 2020-07-09T06:53:27+00:00 July 10th, 2020|

UPM Plywood introduces a new water-repellent plywood that enables efficient and effortless construction even in changing weather and humidity conditions.

The water repellent, yet breathable surface slows down the absorption of moisture into the panel while allowing it to evaporate. Thanks to the wood-based treatment agent, the product is a genuinely sustainable and safe choice made from renewable raw materials.

The new range has been designed for structural uses and it provides significant benefits for developers and builders. Image credit: UPM

The new range has been designed for structural uses and it provides significant benefits for developers and builders. Image credit: UPM

Designed for structural uses, it provides significant benefits especially for developers and builders. “Wood construction is growing in popularity and we want to offer innovative and responsible solutions to it. Our water repellent WISA-SpruceWR plywood can withstand momentary exposure to rain without the need to immediately protect it from getting wet. The builders at the site can focus on the actual construction work as they no longer need to spend time covering materials when the weather changes,” says Olli Wirén, End Use Manager at UPM Plywood.

It is available in four common thicknesses (12–21 mm), in both straight-edged and easy-to-install tongue-and-groove options. Made entirely of spruce, its technical properties are the same as those of regular WISA-Spruce plywood: the panel’s strength and light weight make it ideal for all kinds of timber frame construction, such as walls and floors.

The water repellent treatment further enhances the excellent properties of spruce plywood. “Wood swells when it gets wet, which can cause problems and extra work in construction. Thanks to the water repellent treatment on the surfaces and edges, the product retains its dimensional accuracy and shape better in case of sudden rain and also recovers faster than usual. The construction work becomes easier and faster when the worked edges lock in place more securely during installation, the seams remain tight and the panel does not require a long time to stabilise before installation,” says Riku Härkönen, Product Manager at UPM Plywood.

The water-repellent treatment applied during manufacturing is done with a wood-based substance that contains no harmful chemicals. “The panel’s water repellent coating is breathable, which means that it also allows moisture to evaporate. And because less moisture is absorbed into the panel, it also dries faster than usual. The evaporation of moisture from the wood prevents possible structural and health problems later on,” Härkönen points out.

Third-party verified and internationally comparable Environmental Product Declarations (EPDs) are available for all UPM’s WISA plywood products. These EPDs help contractors, builders, and designers to better understand the products’ environmental impact throughout their whole lifecycle, from raw material sourcing to disposal. UPM Plywood’s EPDs have been created for four product groups: coated and uncoated spruce plywood, and coated and uncoated birch plywood.

In Finland, UPM Plywood’s EPDs have been approved and published by the Building Information Foundation RTS sr. The EPDs have also been published on the international ECO Platform EPD list. Therefore, they have been approved in all European EPD programmes that are part of the system.