Plain Polyurethane Cornice Selection and Application Guide

Plain polyurethane cornices are manufactured from high-density rigid polyurethane featuring a closed-cell structural composition. The material maintains a technical density range of 150 to 150-220 kg/m³ (production target ~160 kg/m³), with an optimum production target of approximately 150-220 kg/m³ (production target ~160 kg/m³). This high density provides structural rigidity while keeping the profile light enough for overhead installation.

Key performance characteristics of rigid polyurethane cornices include:

• Thermal Resistance: Operational stability across a temperature range of -100 °C / +80 °C without warping or cross-sectional distortion.
• Moisture Resistance: Water absorption remains strictly below 1%, preventing swelling or internal deterioration in humid environments.
• Factory Preparation: Profiles are delivered with a factory-applied primer layer, providing a balanced surface for final coat adhesion.

Selecting the cross-section of a plain polyurethane cornice depends directly on the vertical clearance and spatial proportions of the room. Using an oversized profile in a low-ceiling room visually compresses the space, whereas an undersized molding in a tall hall loses visual impact.

Architectural proportions generally follow these height-to-profile guidelines:

• Ceiling Height under 2.60 meters: Select profiles with a vertical wall drop between 6 cm and 10 cm to maintain vertical openness.
• Ceiling Height between 2.60 and 3.00 meters: Use medium-scale cornices with a vertical projection of 10 cm to 14 cm.
• Ceiling Height above 3.00 meters: Choose prominent profiles measuring 15 cm to 20 cm in vertical drop to maintain visual scale.

For symmetric architectural lines, balance the wall drop and ceiling projection ratios according to the ceiling light placement and curtain track clearances.

Accurate quantity calculation for plain polyurethane cornices requires measuring the linear perimeter of every wall segment at the actual ceiling line, rather than along the floor trim line, as wall plumb variations can alter dimensions.

Calculate the total material required using the following steps:

• Measure each continuous wall segment in meters and sum the total perimeter.
• Add a mandatory 10% waste allowance to the total linear meterage to cover material lost during 45-degree miter cuts at internal and external corners.
• Divide the total required linear meters by the standard profile unit length (typically 2.00 meters) and round up to the next full profile unit.

Accounting for corner cuts prior to ordering avoids site delays and prevents batch color variances during project execution.

Mounting plain polyurethane cornices requires strict adherence to combined chemical bonding and mechanical anchoring rules. The mounting substrate must be dry, structurally sound, and free of dust or loose paint layers.

The installation sequence must follow these technical requirements:

• Adhesive Selection: Polyurethane (PU) assembly adhesive must be applied continuously along the ceiling and wall contact grooves. The use of standard silicone is strictly forbidden, as it fails to establish a rigid bond with polyurethane substrates.
• Corner Jointing: All corner intersections must be cut precisely at a 45-degree miter angle using a dedicated miter box or compound saw.
• Mechanical Fixation: Mechanical securing with drywall screws is mandatory. Drive screws through the profile into the wall at intervals of 40 cm to 50 cm to hold the molding in place while the adhesive cures completely.

Once the polyurethane assembly adhesive has cured, joint finishing ensures a continuous profile appearance along extended wall runs. Fill all countersunk screw heads and profile butt joints with joint putty or elastomeric seam filler.

Complete the surface preparation and painting according to these steps:

• Allow joint filler to cure fully, then sand smooth using 180-220 grit sandpaper to achieve an even plane across joints.
• Applying an additional layer of primer over sanded joint areas is optional, but helps equalize surface absorption before the topcoat.
• Apply two complete coats of water-based or solvent-based interior paint over the factory-primed profile.
• For exterior facade applications, using UV-resistant exterior paint is mandatory to protect the polyurethane material from direct solar degradation over time.

Avoiding common field errors saves time and ensures structural integrity during plain polyurethane cornice installation projects evaluated under Polure technical criteria.

Review this checklist before purchasing and mounting:

• Mistake 1: Relying solely on adhesive. Omitting mandatory mechanical screw fixings leads to joint separation over time due to building movement.
• Mistake 2: Using silicone instead of PU adhesive. Silicone lacks chemical compatibility and structural shear strength for rigid polyurethane profiles.
• Mistake 3: Unpainted exterior use. Installing profiles outdoors without UV-resistant paint leads to yellowing and surface degradation under sunlight.
• Pre-Purchase Check: Confirm total linear meterage including 10% corner waste, verify ceiling height matches selected profile drop, and source high-grade polyurethane assembly adhesive.

Düz kartonpiyer tedariki öncesinde şantiyede ve projede belirli kontrol noktalarının gözden geçirilmesi gerekir:

• Mekan tavan yüksekliği ile profil kesit yüksekliği arasındaki oran doğrulanmalıdır.
• Metraj hesabı yapılırken en az %10 oranında fire payı dahil edilmelidir.
• Tedarik edilecek ürünlerin 150-220 kg/m³ (production target ~160 kg/m³) yoğunluk aralığında ve kapalı hücreli rigid poliüretan yapıda olduğu teyit edilmelidir.
• Düz kartonpiyer profilleri dekoratif elemanlardır, yapısal yük taşımazlar. Bu ürünlerin üzerine yük bindirilmemelidir.
• Montaj öncesinde PU yapıştırıcı, dübel, vida, esnek macun ve 180-220 grit zımpara gibi sarf malzemeleri hazır bulundurulmalıdır.
• Dış cephe uygulamalarında UV korumalı boya planlaması yapılmalıdır.