Tamlyn XtremeFlashing Butyl Tape — Self-Sealing Waterproofing for Windows, Doors & Wall Penetrations
XtremeFlashing™ (WSB20-12) is a self-adhering, self-sealing butyl waterproofing tape engineered for professional use around windows, doors, building seams, pipes, electrical conduits, and through-wall flashing details. It is constructed from a polymer film coated with Tamlyn's Broad Temperature Spectrum (BTS™) butyl adhesive — a formulation designed to perform reliably across extreme temperature ranges. A peel-away release liner protects the adhesive until installation. This 12-inch-wide variant is suited for wider flashing applications where standard narrower tapes are insufficient.
Unlike conventional flashing tapes that rely on acrylic or standard pressure-sensitive adhesives, the BTS™ butyl adhesive in XtremeFlashing™ will not crack, dry out, run, or stain — even under sustained thermal stress. It bonds aggressively to all common building materials and self-seals around punctures caused by nails, staples, and screws, eliminating the need for additional sealant at fastener penetrations.
Key Features & Benefits
BTS™ Broad Temperature Spectrum Butyl Adhesive
The BTS™ adhesive maintains consistent adhesion and flexibility across extreme temperature swings — critical for installations in climates with harsh winters or high summer heat. Contractors working in variable conditions can rely on the tape to maintain its seal without reapplication or backing material failure.
Self-Sealing Around Fasteners
The butyl adhesive self-seals around nails, staples, and screws driven through the tape, eliminating a common moisture infiltration point in standard flashing tape systems. This reduces the need for back-filling punctures with sealant and speeds up installation without sacrificing waterproofing integrity.
No Cracking, Running, Drying, or Staining
Butyl adhesive maintains uniform thickness and does not degrade over time the way acrylic-based alternatives can. For contractors, this means long-term performance without the risk of adhesive bleed-through or staining of adjacent finishes and building materials.
Protection Against Water, Air, Insect, and Noise Infiltration
XtremeFlashing™ provides a multi-functional barrier — not just waterproofing but also an air seal and barrier against insect and noise infiltration. This makes it a single-material solution for multiple envelope performance requirements at rough openings and penetrations.
Integrates With Wall System Components
Designed to work as part of a complete Tamlyn water management system alongside TamlynWrap®, XtremeSealant™, and XtremeSeam™ Tape. When installed shingle fashion, it properly directs moisture away from the building envelope and meets system warranty requirements.
Compatible With Most Common Building Materials
Bonds reliably to OSB, plywood, concrete, masonry, metal, and most building wraps without requiring a primer. This broad substrate compatibility reduces prep time and makes the product suitable across a wide range of residential and commercial construction types.
Common Applications
Window and Door Rough Opening Flashing
WSB20-12 is ideal for flashing wide rough openings where a 12-inch tape provides adequate coverage at sill, jamb, and head conditions without overlapping multiple narrower strips.
Building Seams and Transitions
Applied at structural panel seams and transitions between dissimilar substrates to prevent water and air intrusion at joints that are difficult to seal with sealants alone.
Through-Wall Flashing Details
Suitable for use at wall penetrations including pipes, conduits, and mechanical sleeves where a conformable, self-sealing tape can wrap irregular geometry and maintain a continuous waterproof barrier.
General Construction Waterproofing
Used across a range of field conditions in both residential and light commercial construction to create watertight seals at any wall penetration or discontinuity in the weather-resistive barrier.
Flashing as Part of a System Warranty
Required component when installing a Tamlyn Water Management System to qualify for the 25-Year Product and Labor warranty — makes it a specified product on projects with long-term performance documentation requirements.
XtremeCorners and Bowtie Flashing Details
Works in conjunction with XtremeCorners™ and bowtie installation methods to address inside and outside corner conditions that are high-risk water infiltration points in the building envelope.
Compatible Materials
- OSB (oriented strand board)
- Plywood sheathing
- Concrete and masonry substrates
- Metal framing and flashing components
- Building wraps and housewraps
- Most common polymer-based building materials
- Wood framing and dimensional lumber
- Fiber cement substrates
Available Sizes
| Item ID | Width | Length | Thickness | Best For |
|---|---|---|---|---|
| WSB20-4 | 4" | 75 ft | 20 mil | Narrow jamb flashing, fastener sealing, small penetrations |
| WSB20-6 | 6" | 75 ft | 20 mil | Standard window and door sill and jamb flashing |
| WSB20-9 | 9" | 75 ft | 20 mil | Head flashing and wider rough opening conditions |
| WSB20-12 | 12" | 75 ft | 20 mil | Wide sill pans, large rough openings, panel transitions |
Product Documents
Application Instructions
Surface Preparation
- Ensure substrate is clean, dry, and free of dust, oil, and loose debris before applying tape.
- Verify substrate temperature is within the product's rated application range for proper adhesion.
- For maximum adhesion on porous substrates, confirm the surface is structurally sound and free of frost.
Tape Installation
- Remove the release liner gradually as the tape is applied — do not pre-strip the full liner before positioning.
- Press the tape firmly into the substrate using a roller or hand pressure to ensure full contact and eliminate air voids.
- Install tape SHINGLE FASHION — lower courses must be applied first so that upper courses overlap and direct water away from the building envelope. This is required for proper moisture management.
- At corners, use XtremeCorners™ pre-formed pieces or the approved bowtie method to ensure continuous coverage at inside and outside corner conditions.
Fasteners
- The BTS™ butyl adhesive will self-seal around nails, staples, and screws driven through the tape — no additional sealant is required at fastener locations under normal conditions.
System Integration
- For full 25-Year Product and Labor warranty coverage, install XtremeFlashing™ as part of the complete Tamlyn Water Management System including TamlynWrap®, XtremeSealant™/BrunnoSeal®, XtremeSeam™ Tape, and cap fasteners.
- Register the project at warrantyreg@tamlyn.com or by fax at 281-499-8948 using the Tamlyn Warranty Registration form.
Technical Specifications
| Specification | Details |
|---|---|
| Item ID | WSB20-12 |
| Width | 12 inches |
| Length per Roll | 75 feet |
| Thickness | 20 mil |
| Adhesive Type | BTS™ Broad Temperature Spectrum Butyl |
| Facing Material | Polymer film |
| Release Liner | Yes — peel-away liner removed during installation |
| Self-Sealing | Yes — seals around nails, staples, and screws |
| Available Widths | 4", 6", 9", 12" |
| Product Warranty | 15 Years Limited (product only) |
| System Warranty | 25 Years Product and Labor (when installed as full Tamlyn Water Management System) |
| Installation Method | Shingle fashion required for proper moisture management |
| Manufacturer | R.H. Tamlyn & Sons, Inc. |
Frequently Asked Questions
Q: Does XtremeFlashing™ butyl tape require a primer before application?
A: No primer is required for most common building substrates including OSB, plywood, concrete, masonry, and metal. The BTS™ butyl adhesive bonds aggressively to these materials without additional surface treatment, provided the substrate is clean and dry.
Q: What is the correct installation direction for this flashing tape?
A: XtremeFlashing™ must be installed shingle fashion — sill flashing is applied first, then jambs over the sill, then the head over the jambs. This sequencing ensures water is directed away from the rough opening and does not become trapped behind tape laps.
Q: Is this tape compatible with the Tamlyn system warranty?
A: Yes. XtremeFlashing™ is a required component of the Tamlyn Water Management System and is covered under the 15-Year Product Only Limited Warranty as a standalone product. When installed as a complete system with TamlynWrap®, XtremeSealant™, XtremeSeam™ Tape, and cap fasteners, the project is eligible for a 25-Year Product and Labor Limited Warranty upon project registration.
Q: Will I need to apply additional sealant around fasteners driven through the tape?
A: No. The BTS™ butyl adhesive self-seals around nails, staples, and screws, closing around the fastener shank to maintain the waterproof barrier without requiring a secondary sealant application at each penetration point.
Q: Why choose 12-inch-wide tape over the 4" or 6" versions?
A: The 12-inch width (WSB20-12) is suited for wide sill pan flashing, large rough openings, and panel-to-panel transitions where narrower tape would require multiple parallel strips with overlap seams. Fewer seams mean fewer potential failure points and faster installation on wide conditions.
Q: How do I file a warranty claim if there is a product failure?
A: Contact Tamlyn within 30 days of discovering the potential defect at www.tamlyn.com or by calling 1-800-334-1676. Provide proof of purchase, proof of installation within the warranty period, and allow Tamlyn a 60-day window to inspect the project and collect product samples for evaluation.