This XtraFlash™ Membrane fl­ashing installation guide is intended for use when a weather resistant barrier (housewrap) is to be applied after window installation and the head, sill and jamb ­flashing will be applied over the face of an integral mounting fl­ange on the window (i.e. Method A in ASTM E2112, AAMA2400-02). Other installation methods may be employed. In all cases the installer should refer to the window manufacturer’s installation instructions, as well as, local building codes and best practices for window and door installation techniques.

Prior to the installation process, the XtraFlash™ Membrane fl­ashing materials can be pre-cut using the rough opening (RO) dimensions and formula in the following table. Surfaces should be clean and free of debris and dust. Install on a dry surface without ice and snow. Cover within a 6 month time frame.

  • Easy Installation
  • Superior Durability
  • Compatible with all Standard Windows & Doors
  • Protects against Water Intrusion

STEP 1 – Sill Installation

Attach the XtraFlash™ Membrane ­flashing to size of window opening adding  12” total to extend past either side of rough opening by 6”. Peal ½ of the release paper on back side of ­flashing allowing for easy installation. Apply to outside of window opening by sticking the butyl adhesive on ­flashing to the rough opening (do not secure bottom half of sill fl­ashing backing intact for housewrap to tuck underneath for proper water drainage). XtraFlash™ Membrane ­flashing should be ­flush to the edge of the sill.

STEP 2 – Install Window

Install window as per manufacturer’s recommendation using 3/8’ bead of (XtraBond® 9500) sealant of all 4 sides of back side of window fin. Set the window. If sealant is used, ensure all excess sealant is removed from nailing fl­ange and surrounding area to provide a smooth continuous substrate.

STEP 3 – Side Jamb Flashings

Cut XtraFlash™ Membrane Flashing to size of window side (jamb) openings adding 12” total to extend past upper and lower edge of rough opening by 6”. Peal the release paper on back side of ­flashing allowing for easy installation. Apply the precut fl­ashing onto the nailing ­flange after the window has been installed; extend over the bottom sill fl­ashing for proper drainage. Roll the fl­ashing adhesive if necessary to create a tight bond. Repeat on both sides of window.

STEP 4 – Head Flashing

Apply pre-cut header XtraFlash™ Membrane Flashing on top of the window nailing fl­ange by pealing the release paper on back side of fl­ashing, exposing the butyl adhesive allowing for easy installation. Apply the precut fl­ashing on top of the nailing fl­ange extending 6” beyond each side of the window opening. Roll fl­ashing firmly into place as necessary creating bond of ­flashing to opening sealing for any moisture intrusion – making sure top head fl­ashing is installed over the 2 side ­flashing.

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