Keene Building Products KeeneFlash™ 300

MULTIPURPOSE FLASHING & REPAIR TAPE

KeeneFlash 300 is a clear butyl flashing tape designed for sealing building penetrations such as windows, doors, dryer vents, and utility pipes. Its aggressive butyl adhesive system creates a permanent seal to protect buildings from air and water infiltration. The flat film backing provides strength and durability against rips, tears, and punctures.

KeeneFlash’s unique design makes it the go-to flashing and repair tape on modern job sites. Whether used as a window & door wrap, roof deck tape, joint & transition tape, or roof repair tape, KeeneFlash covers a wide variety of building envelope needs. With outstanding performance, ease of handling, UV stability, and multiple widths available, KeeneFlash is the “Duck Tape®” for the building envelope.

FEATURES AND BENEFITS

• Highly conformable film backing: Flexible for bending around edges, corners, and transitions

• Wide installation temperature range: Suitable for all regions

• Self-healing after puncture: Maintains integrity even after damage

• Permanent weather-tight seal: Works on most clean, dry building surfaces

• Compatible butyl adhesive: Works with sealants and flexible/rigid PVC window flanges

• Easy-to-remove release liner: Moisture stable for simple installation

APPLICATIONS

• Window and door openings (headers, jambs, window flanges, sills, thresholds)

• Dryer vents and pipe penetrations

• Sealing joints and seams in exterior sheathing panels

• Foundation sill plates

• Deck to wall intersections

• Other non-roof detail areas

BASIC INSTALLATION

• Substrate must be dry.
• Substrate needs to be clean and free of dust and dirt.
• Damaged substrate should be repaired before installation.
• Apply in a shingling fashion when multiple courses are needed.
• Ensure all protruding fasteners are removed.
• Once installed use a hand roller to roll all installed KeeneFlash 300 to ensure proper adhesion.

SIZES AND PACKAGING

RESOURCES

• Technical Data Sheet