Adheseal PU15 Polyurethane Adhesive

When movement joints demand flexibility and fenestration perimeters need a durable, paintable seal, you need a product that performs. Adheseal PU15 provides that solution: a low modulus, highly flexible polyurethane sealant engineered for dynamic indoor and outdoor movement and connection joints. It cures to a permanently elastic, paintable, and durable finish, ensuring integrity where constant expansion and contraction are inevitable.

Why this product exists

Adheseal PU15 was developed as a low modulus (Shore A 15) elastomeric polyurethane sealant to address the need for a highly flexible solution in dynamic indoor and outdoor movement and connection joints. It is specifically formulated to accommodate significant movement (up to ±25%) and provide excellent paintability and adhesion across diverse construction materials. This ensures joint integrity and long-term performance where less flexible sealants might crack or delaminate due to constant expansion and contraction. It specialises in highly flexible joints where its elasticity is critical for accommodating dynamic movement, making it suitable where higher modulus sealants would restrict movement, induce stress, or be otherwise unsuitable.

The numbers that matter

• A Shore A hardness of 15 (after 14 days) signifies a soft, elastic sealant. This low modulus is critical for absorbing stress in dynamic joints without delaminating or tearing, unlike stiffer alternatives.
• This ±25% movement capability, classified as Type F Class 25 LM under ISO 11600, allows a 10mm joint to expand and contract by 2.5mm each way. This confirms its suitability for joints subject to significant structural or thermal shifts.
• An elongation to break exceeding 600% provides a substantial safety margin. This ensures the sealant can stretch far beyond its working movement range without tearing, even under extreme, unexpected strain.
• The ability to be painted with acrylic, oil, and rubber-based paints allows seamless aesthetic integration. This ensures joints blend with surrounding surfaces, crucial for maintaining a clean finish on any project.

What it's like to use

Adheseal PU15 is a ready-to-use, single-pack system applied from a 600ml foil sausage. It tools easily, with a working time of 25 minutes and a skinning time of 60 minutes (at 23ºC & 50% RH), allowing for precise finishing. Ensure surfaces are clean, dry, and sound before application. For non-porous substrates like aluminium or powder-coated metals, prepare surfaces with Adheseal 50A Surface Prep. For porous materials like concrete or brick, prime with Everflex Supaprime Sealant Primer. Always perform an adhesion test before full application, especially on less common substrates. For cleanup of wet sealant, use Xylene on tools and spills. Cured product requires mechanical removal. Clean skin with Adheseal Hand Wipes.

Where this product excels

• Fenestration details: Use it for perimeter sealing of windows, doors, and curtain walls, where it accommodates differential movement between frames and structures, providing a long-lasting, weatherproof seal.
• Precast and tilt-up panels: Its high elasticity prevents joint failure in expansion joints, accommodating structural movement and thermal cycles in facades, balconies, and podiums.
• Metal cladding and bolted lap joints: Form a durable, watertight seal on metal surfaces, including aluminium fabrication and galvanised steel, without causing corrosion.
• Vehicular and marine manufacturing: Its tough, durable, and permanently flexible nature withstands vibration and environmental exposure in transport and marine applications.

How it fits in a real system

Adheseal PU15 typically acts as the final seal within joint sealing sequences. For optimal adhesion and system performance on various substrates, apply it after preparing the surface. For instance, when sealing movement joints in concrete, you would first prepare porous surfaces with Everflex Supaprime Sealant Primer, ensuring a strong bond with the substrate before applying PU15 as the final sealant. For non-porous substrates like anodised aluminium, Adheseal 50A Surface Prep precedes PU15.

Choose this when

• When sealing dynamic indoor and outdoor movement and connection joints requiring a low modulus, highly flexible, and paintable polyurethane sealant.
• When the joint needs to accommodate significant movement, such as in fenestration details, precast/tilt-up panels, or metal cladding.
• When a tear-resistant, permanently flexible, and waterproof seal is required that offers excellent weathering resistance and good mould and mildew resistance.
• When working with common building materials like metal, wood, concrete, fibreglass, or powder-coated surfaces, where excellent adhesion is crucial.

Don't use this when

• Not for: Long-term water immersion or internal swimming pool applications, especially where chlorine levels exceed 5ppm.
• Not for: Totally confined spaces, as the sealant requires atmospheric humidity to cure.
• Not for: Structural glazing; use specialised glazing sealants like N-80 or N-60 instead.
• Not for: Adhering mirrors without prior testing; consider products like Hi-Power/MS609.
• Not for: Direct contact with bituminous, natural rubber, EPDM rubber surfaces, or any material that might leach oils, plasticisers, or solvents.
• Not for: Some natural stone types without prior stain testing.

Related products

• Adheseal PU50 High-Modulus Polyurethane Adhesive
• Adheseal PU25 Fast-Cure Polyurethane Sealant