Weather Stripping Technical Details
Materials and Composition
The efficacy and longevity of weather stripping are largely determined by its material composition. Common materials include various polymers, fabrics, and metals, each offering distinct properties suited for different applications. EPDM rubber ethylene propylene diene monomer and silicone are prized for their excellent resistance to extreme temperatures, UV radiation, ozone, and weathering, making them ideal for exterior applications where durability is paramount. These materials maintain flexibility over a wide temperature range, ensuring consistent sealing performance.
Polymer Based Materials
Vinyl weather stripping, often made from PVC polyvinyl chloride, offers good durability and flexibility at a lower cost. It is commonly found in fin seals and compression strips. Foam weather stripping, typically open or closed cell foam, provides a compressible seal for irregular gaps. Closed cell foam resists moisture better, making it suitable for damp environments, while open cell foam offers good sound dampening but can absorb water.
Fabric and Brush Seals
Felt weather stripping, historically used, is less durable and susceptible to moisture absorption but can be effective for low-traffic interior applications. Brush or fin brush seals, commonly found on sliding doors and garage doors, utilize synthetic fibers like nylon or polypropylene to create a barrier against air and debris while allowing movement. These are excellent for uneven surfaces or where a tight compression seal is impractical.
Metal and Rigid Materials
Metal weather stripping, often made from bronze, aluminum, or stainless steel, offers exceptional durability and a rigid, long-lasting seal. Interlocking metal strips create a mechanical barrier. Door sweeps, typically aluminum or vinyl with a brush or rubber seal, are installed at the bottom of doors to seal gaps against the threshold.
Application Types and Installation Methods
Weather stripping products are designed with specific profiles and installation methods to address various types of gaps and opening mechanisms. Compression weather stripping relies on the material being compressed to fill a gap, providing a continuous seal. These are commonly used around door and window sashes, often integrated into the frame or applied as a flexible bulb or V-strip.
Adhesive Backed Seals
Self-adhesive weather stripping, usually foam or rubber, offers easy peel-and-stick installation for quick gap sealing. While convenient, the adhesive bond's longevity can vary depending on surface preparation, temperature, and material quality. These are best for smaller, less exposed gaps and light-duty applications.
Fastener Based Installation
For more robust and permanent installations, weather stripping can be fastened mechanically with nails or screws. This method is common for rigid vinyl, metal strips, and certain types of door bottoms or sweeps, ensuring a secure attachment that can withstand frequent use and environmental stresses. Examples include tension seal V-strips and specific door shoe designs.
Performance Characteristics
Key performance metrics for weather stripping include its air leakage rate, thermal resistance, acoustic properties, and resistance to environmental degradation. Effective weather stripping significantly reduces air infiltration, which is critical for maintaining indoor air quality and controlling humidity. Its ability to create a consistent seal directly impacts a building's energy efficiency by preventing conditioned air from escaping and unconditioned air from entering. Acoustic performance is also a consideration, as a tight seal can help dampen sound transmission.
Resistance to UV radiation, ozone, and extreme temperatures ensures the material does not degrade prematurely, losing its flexibility or sealing capability. The durometer hardness of rubber and polymer seals affects their compression set resistance, ensuring they rebound and maintain their shape after being compressed, providing a long-term seal without flattening out.