Do I need butyl tape under metal roofing?

Yes, most metal roofing manufacturers require butyl tape sealant at panel laps, trim, and penetrations for warranty compliance.

Does butyl tape dry out?

No, butyl tape remains permanently flexible and tacky. It never cures, dries, or hardens.

Butyl Tape

Adhesives & Sealants

Tapes

Budget: $5-$10 (1/2" x 30 ft) | Mid-range: $10-$18 (3/4" x 50 ft) | Premium: $15-$30 (1" or wider, longer rolls)

Butyl Tape: Waterproof Putty Tape for Roofing & Metal Panels (2026)

Prepared by Lumberama's Building Materials Team

|Last updated May 25, 2026|Sources & methodology

Butyl tape is a flexible, non-curing adhesive sealing tape made from butyl rubber that provides a waterproof seal between building components. It is commonly used under metal roofing panels, between flashing layers, and around penetrations. Unlike caulk, it remains permanently flexible and never hardens or cracks.

Key Features

Permanently flexible seal; Never cures or hardens; Waterproof butyl rubber composition; Available in multiple widths and thicknesses; Self-adhering with no tools needed

Specifications

Material: butyl rubber | Widths: 1/2"

3/4"

1-1/2" | Thickness: 1/16"

1/8" | Roll lengths: 30 ft

50 ft | Temperature: -40°F to 200°F | Color: black

gray

Applications

Under metal roofing panel laps; Between metal flashing and roof surface; Around pipe and vent penetrations; Sealing gutter end caps; RV and mobile home sealing

Installation Overview

Clean surfaces of debris and moisture. Unroll tape and press onto clean surface. Position second material on top. Apply pressure to compress tape and create seal. Tape remains workable - components can be repositioned if needed.

Pros & Cons

Pros

✓ Permanently flexible waterproof seal; Easy peel-and-stick application; Never hardens or cracks; Works in extreme temperatures

Cons

✗ Messy to handle; Not for visible exterior joints; Can be squeezed out under heavy pressure; Not as strong as adhesive bonding

Top Brands

Cofair

Eternabond

Pella

Code Requirements

Required by many metal roofing manufacturers at panel laps and penetrations. Must meet manufacturer specifications for warranty compliance.

Buying Tips

Match tape width to your metal roofing manufacturer's specifications; Keep rolls at room temperature before application for easier handling; Stock extra for flashing and penetration sealing