Pro Guide to Flashing a Window

Professional contractors emphasize the importance of properly installing and flashing a window to protect both the window and the surrounding frame from water damage. Mistakes made during the installation process can lead to expensive repairs later and may tarnish a contractor’s reputation.

Shurtape Technologies recently released FrogTape Pro Grade Flashing Tape, an all-weather, high-performance flashing tape. Shurtape partnered with Rich Morse to share expert tips on window installation and best practices for using FrogTape Pro Grade Flashing Tape.

Rich Morse owns a property inspection company responsible for performing construction management services, including pre-construction services for the rehabilitation of existing structures, and on new construction. The following steps outline Rich's procedure for properly installing a window with the use of FrogTape Pro Grade Flashing Tape to deliver a secure fit.

Steps for Window Installation

1.         Preparing to flash a window: Starting 3 inches below the window opening, staple a piece of vinyl flashing across the wall, ensuring it extends beyond the window width by at least one inch on each side.

2.         Apply Flashing Tape: Place a strip of flashing tape across the top of the vinyl flashing, starting 1 inch above the top edge, and extending 2 inches beyond each side.  Use a hand squeegee to apply pressure over the tape, ensuring a strong, even seal.

3.         Wrap and Seal the Sill Area: Use 9 inch flashing tape and put it all the way inside of the 2 x 4 wall, pressing it fully into the base of the window opening and extending it two inches up both vertical sides of the frame. Use the squeegee to firmly adhere the tape, focusing on the seal at the corners. Pull the tape outward to cover the wall surface, overlapping the initial 4 inch layer. Stretch the corners where needed. If unable to stretch across the plywood, use the bowtie method by making diagonal cuts at the outer sill corners, then fold, and secure the tape.

4.         Seal the Sides and Top: Starting at the sill’s right edge, extend flashing tape about 1.5 inches inside and 2.5 inches outside the 2x6 stud. Repeat this step for the left side and the top edge, ensure firm sealing with the squeegee.

5.         Prepare for Installation: Apply flashing tape across the top of the window opening, ensuring overlap with the side flashing. Once all layers are sealed and smooth, the window is ready for installation.

Best Practices when using FrogTape Pro Grade Flashing Tape

1.     Add at least one layer of tape along the top of the window and over the window flanges to ensure it is sealed off. Up to three layers of tape may be added as FrogTape Pro Grade Flashing Tape maintains its integrity when stretched.

2.     Overlap at least 1.5-2 inches, of tape over the edges of the window frame.

1. Seal the corner where the edges meet using one of the following techniques:

1.     Stretch the tape out to the corner land using the hand squeegee tool.

2.     Make a slit at the corner, then, at that same corner, cut the tape at a 45-degree angle to help it lay more smoothly. Use the bowtie method by creating a "bowtie" shape with the tape and place it in the corner to ensure a tight seal. Using this technique, it's possible to apply up to three layers of tape for added protection.

FrogTape Pro Grade Flashing Tape features

FrogTape Pro Grade Flashing and Waterproofing Tape’s high-performance UV acrylic adhesive provides many benefits over the standard butyl adhesive used in many flashing tapes, including:

• Adhesive Technology: UV technology creates a stable adhesive system that won’t break down over time, but rather creates a stronger bond

• Flexibility: Better performance and conformability across a range of hot and cold temperatures and climates

• Adhesion: Excellent adhesion to challenging building materials, including difficult-to-stick-to and rough or uneven surfaces – with no primers required

• Workability: Initially repositionable during install to ensure the job is done right

• Performance: Improved compatibility with caulks and sealants

• Sustainability: A more sustainable manufacturing process – without solvents, thermal ovens, air pollutants and greenhouse gasses – for a lasting, positive impact on our planet