Polyurethane Exterior Window Surround Casings

Architectural Definition and Facade Integration

Window surrounds represent one of the most critical elements in defining the structural character of a building facade. Within the Polure product ecosystem, our high-density polyurethane window architraves—often searched by trade professionals as a premium polyurethane window surround casing—offer a technologically advanced alternative to traditional, heavy materials. Unlike heavy concrete, fragile plaster, or low-density expanded polystyrene (EPS) options, these engineered profiles deliver sharp geometric lines and pristine surface finishes that allow architects to execute complex facade designs with absolute precision.

Technical Specifications of High-Density Polyurethane

Engineered for harsh outdoor environments, these profiles feature a high density of 150-220 kg/m³ (production target ~160 kg/m³), providing a wood-like hardness while maintaining a lightweight profile that avoids adding dead load to the building envelope. Key engineering characteristics include:

• Moisture Resistance: With a closed-cell structure and water absorption of less than 1%, the material prevents rotting, swelling, and water ingress.
• Thermal Stability: Exhibiting high dimensional stability, these profiles do not warp, shrink, or expand under extreme temperature fluctuations ranging from -100 °C / +80 °C.
• Structural Safety: The material is self-extinguishing, meaning it ceases to burn once the external flame source is removed.

These properties make the profiles highly suitable for demanding climates across Europe, where traditional timber or plaster alternatives fail due to moisture exposure and freeze-thaw cycles.

Replacing Plaster, Wood, and EPS Systems

Historically, decorative framing required expensive stone masonry or high-maintenance timber. Modern alternatives like EPS often lack the impact resistance needed at ground level and are easily damaged by birds or physical impacts. Our high-density profiles offer superior impact resistance and sharp detailing. Large-scale models, such as KPEN11 (217x2000x2280 mm) or KPEN29 (257x2080x2330 mm), provide substantial architectural presence without the structural risks associated with heavy precast stone. They function as a highly durable exterior window casing, protecting the window opening while enhancing the building's exterior market value.

Surface Preparation and Coating Guidelines

Each profile is shipped from our factory with a pre-applied primer coat, which is designed to prepare the surface for final painting and improve paint adhesion. The surface is compatible with high-quality water-based and synthetic paints. However, professional contractors must note that paint manufacturers typically do not guarantee the longevity or adhesion of their products unless their specific brand-approved primer is applied to the substrate beforehand. For this reason, applying an additional primer layer on-site is an optional step, and the decision remains with the customer. Polure does not guarantee any paints applied to its products and accepts no liability for paint performance. For all exterior installations, the application of a high-quality, UV-resistant paint is mandatory to prevent natural yellowing of the unpainted material over time.