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For sealing expansion joints, roof cladding, and window or door perimeters against weather, Biyseal Acrylic Impregnated Foam provides a highly compressible barrier that adapts to continuous joint movement. This high-density polyurethane foam is impregnated with an acrylic solution, allowing it to expand and contract dynamically while maintaining its elasticity indefinitely.
How it works
Biyseal Acrylic relies on physical compression to block environmental elements. The level of protection scale directly with how much the foam is compressed during installation. It can be compressed down to 10% of its original width and will recover to more than 90% of its dimension after repeated compression and expansion cycles.
Numbers that matter
- 25% compression: The minimum threshold required to form a reliable seal against air, dust, and vibration.
- 50% compression: The compression level required to establish a secure seal against moisture.
- 75% compression: The level required to seal joints against heavy rain and direct water ingress.
- -10°C to +70°C: The service temperature range across which the foam maintains its sealing performance.
Where to use it
This foam is suitable for sealing a variety of joints and interfaces, including:
- Roof cladding across all standard roofing materials and Custom Orb profiles.
- Back channel foam for polycarbonate sheet installations.
- Expansion joints in concrete and brickwork.
- Window and door perimeters adjacent to concrete, timber, and brickwork.
- Precast concrete panels, air-conditioning systems, and partitions.
- Weather-exposed electrical installations.
- Caravans, motor vehicles, and railway carriage construction.
Installation and handling
Surfaces must be clean and free of grease and oils before application. Ensure the selected foam dimension matches the joint size to achieve the required compression rate. Compress the foam by hand or with a roller immediately before placing it into the joint; the foam will expand quickly to fill and seal the gap. When joining multiple strips, splice the ends at an angle using a wet knife to ensure a continuous joint. Store unused stock away from dust and direct sunlight.
Compatibility and limitations
Biyseal Acrylic is compatible with water-based paints and mastics. Ensure foam dimensions are verified against actual joint widths to prevent under-compression, which compromises the seal against water and drafts.
Frequently asked questions
Can Biyseal Acrylic seal joints exposed to heavy rain?
Yes, Biyseal Acrylic seals against heavy rain when compressed to 75% of its original width. This makes it suitable for exposed cladding gaps or polycarbonate roofing installations where water ingress is a concern.
Is this foam suitable for dynamic joints like precast panel gaps?
Yes, Biyseal Acrylic is engineered for dynamic movement. It offers over 90% elastic recovery, making it suitable for precast concrete joints and modular building interfaces that experience thermal movement.
Can I paint over Biyseal Acrylic foam?
Yes, Biyseal Acrylic is compatible with water-based paints. Ensure the foam has fully expanded and is dry before painting to achieve proper adhesion and finish.
How do I join two strips of Biyseal Acrylic?
To create a continuous seal, splice the ends of the strips on an angle using a wet knife. Then, butt them together firmly to ensure no gaps remain in the joint line.
Applications and benefits
| Application | Key benefit | Primary trades |
|---|---|---|
| Expansion joints in precast concrete | Maintains flexibility and weather resistance under thermal movement with over 90% elastic recovery. | Concretors, builders |
| Back channel for polycarbonate roofing | Fills U-channels to block rain, insects, and dust without wet sealants, tooling, or cure time. | Roofers, glaziers |
| Window and door perimeter sealing | Prevents drafts and water leaks, improving thermal efficiency without relying on perfect gunning or tooling. | Glaziers, carpenters, builders |
| Vehicle, caravan, or trailer assembly | Provides a vibration-resistant and waterproof seal that tolerates on-road movement and temperature changes from -10°C to +70°C. | Fabricators, auto body technicians |
| Electrical and HVAC cabinet sealing | Forms a reliable, flexible gasket seal against weather and dirt ingress without liquid sealants or curing. | Electricians, HVAC technicians |
Step-by-Step Application Guide for Biyseal Acrylic Impregnated Foam:
- Preparation is Paramount: Ensure joint or surface is clean, dry, and free from oil, grease, or dust. For porous surfaces like concrete, brushing or vacuuming may be required. Avoid installing when surfaces are damp.
- Nozzle & Gun Setup: Not required. Biyseal comes as pre-cut strips. Select the correct width for your joint and trim length with a sharp knife or scissors.
- Application Technique: Compress foam manually or with a roller into the joint. Ensure continuous pressure and avoid gaps. Biyseal will self-expand slightly to fill voids.
- Tooling for a Professional Finish: Use a damp knife to compress ends or shape corners. For neat termination, cut at a 45° angle and butt splice with slight overlap if needed.
- Clean-Up: No solvents required. Simply wipe tools clean or discard offcuts. Biyseal has no odour or tack.
- Curing Process: No curing time required. The foam provides immediate sealing performance once installed at proper compression level.
Product limitations
- Not for: Submerged or underwater use. For continuous immersion, use an appropriate product such as Adheseal WetGrab.
- Poor adhesion to: Oily or greasy substrates. Always clean surfaces thoroughly before application to ensure the foam expands and grips effectively.
Safety and handling
Personal protective equipment
Gloves are recommended to prevent minor skin irritation. No harmful vapours or solvents are present.
Ventilation
No special ventilation is required under normal use conditions.
Storage and disposal
Store in a cool, dry place away from direct sunlight. Dispose of waste in accordance with local regulations.
Substrate guide
Proper surface preparation is crucial for the effective compression and sealing performance of Biyseal Acrylic Impregnated Foam.
Concrete (precast or rendered)
Surface prep: Surfaces must be dry and free from dust, laitance, or loose material. Remove any form-release agents or curing compounds.
Primer: Not required for effective compression sealing.
Timber (framing or window reveals)
Surface prep: Ensure timber is clean, dry, and free of sawdust or splinters. Compatible with most treated and untreated softwoods and hardwoods.
Primer: Not required for effective compression sealing.
Polycarbonate sheeting (back channels)
Surface prep: Clean the U-channel profiles to ensure they are free of dust, debris, or moisture, allowing the foam to fit snugly.
Primer: Not required for effective compression sealing.
Metal roofing and cladding
Surface prep: Surfaces must be clean and dry. Remove any oxidation, grease, or loose coatings. Ensure profiles are clear for full foam compression.
Primer: Not required for effective compression sealing.
Aluminium frames or flashings
Surface prep: Clean surfaces to remove any oxidation, grease, or dirt. A clean substrate allows for consistent compression and seal integrity.
Primer: Not required for effective compression sealing.
Biyseal Acrylic Impregnated Foam Physical Properties
| Property | Value |
|---|---|
| Material | Polyurethane Foam, Acrylic Solution Impregnation |
| Compression Performance | 25% blocks air, dust, vibration; 50% blocks moisture; 75% blocks rain and water |
| Elastic Recovery | Recovers to over 90% of original width after repeated compression |
| Temperature Range | -10°C to +70°C |
| Compatibility | Water-based paints and mastics |
| Available Sizes | 25mm x 25mm, 50mm x 25mm |
| Length Per Strip | 2 m |