Butyl Window Sealant

Manufactured by Xiashi Packing, this double-sided butyl window sealant acts as a dedicated accessory for building envelope systems. It is supplied to European and American markets and has been applied in landmark projects including the Zhanjiang BASF Factory Project and Starbucks China Coffee Innovation Industrial Park.

How does It work？

We make this double-sided butyl tape from high-purity butyl rubber. Both sides grab surfaces firmly the moment you apply it. It won’t turn hard, staying bendable all the time. When building materials expand or shrink with temperature swings, the tape moves along with them and stays tightly bonded.

Its double sticky sides stick two membrane sheets together, sealing seams on waterproof breathable or vapor barrier membranes. It keeps rainwater and unwanted air from leaking through overlaps and screw holes.

The soft butyl material conforms to small surface bumps. It maintains a solid seal even around tiny imperfections.

Key Features and Benefits

✅ Reliable lap sealing: Same grip strength on both sides. Built specifically to join waterproof breathable membranes and thermal break films into one continuous sealed line.

✅ Never hardens, always flexible: When materials expand or shift, the tape bends with them. No cracks, no peeling.

✅ Works in cold weather too: Stays pliable down to -40°C in lab testing, so it fits projects across different climates.

✅ Clean formula, no solvents: No volatile chemicals to worry about. A good match for green building specs.

✅ Install cold, no flames: Peel off the liner, press it down, done. No torches, no heating, quick and safe on site.

✅ Handles all kinds of sealing jobs: Membrane overlaps, fastener holes, damaged spots, weak joints—it covers them all.

✅ Holds up over time: Stands up to everyday site conditions and keeps sealing steadily through the life of the building envelope.

Double-Sided Butyl Sealant vs. Other Sealing Options

Applications

Waterproof breathable membrane overlap sealing

Vapor barrier membrane joint sealing

Screw and fastener pinhole penetration sealing

Local membrane damage repair

Building envelope joint reinforcement

Compatible Building Envelope Systems

Steel structures, metal roofing, timber-frame buildings, curtain walls, passive houses and low-energy green buildings, large-scale public and industrial venues.

Project Case Study Reference

✅ Zhanjiang BASF Factory Project

✅ Starbucks China Coffee Innovati

✅ Danzhou Sports Center – Large-Scale Venue Roof & Exterior Wall Enclosure Project on Industrial Park

✅ Large-scale steel-framed industrial plants, wooden structures, and passive low-energy green building projects

FAQs

Q1: Will double-sided butyl window sealant clog the micropores of the waterproof breathable film, thereby affecting its breathability?

A: The adhesive tape is only used at overlapping joints; it does not cover the breathable area of the membrane itself nor affect the overall breathability and drainage performance of the system; it is a supplementary material designed to complement this system.

Q2: Can construction still proceed in low-temperature winter conditions?

A: The butyl window sealant maintains its toughness at-40°C; however, the substrate surface must be dry and free of ice. When the ambient temperature is too low, it is recommended to heat the substrate surface on-site to enhance the initial adhesion performance.

Q3: Can it be exposed directly to outdoor ultraviolet radiation?

A: This butyl window sealant is used as an intermediate overlap sealing layer; under normal operating conditions, it should be applied between two layers of film and is not recommended for prolonged exposure to direct sunlight; for exposed joints, please use specialized external surface waterproof and breathable tape.