In this short instructional video, we’ll show you How-To Prepare a Rough Opening for a Window Installation.

With a complete list of Tools and Step-by-Step instructions in Video, Audio and Text formats, once you’ve selected you Windows, you’ll have everything you need to get the job done right. If you get stuck, or need advice before starting your Window renovation or replacement project, give us a call – we’ll be happy to help.

List of Tools required:

  • Tape Measure
  • Level (4′ Minimum)
  • Hammer
  • Utility Knife
  • J-Roller
  • Construction Stapler
  • 3/8″ Staples

Available at POCO Building Supplies

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Use a J-Roller to smooth out any wrinkles or bubbles in the self adhesive flashing

Prepare a Rough Opening for a Window Installation in 10 Easy Steps

  1. Verify the Rough Opening is Square, level and plumb
  2. Use self adhesive flashing (commonly known as Peel-N-Stick or BlueSkin) to waterproof the sill.
  3. Ensure a min 2″ of material on the vertical surfaces of the wall.
  4. You may need to use 2 pieces of flashing to fully waterproof the opening.
  5. Measure and cut the ‘flashing’ to size and then install on the Rough Opening Sill, making sure to wrap the flashing up 6″ on each jamb.
  6. Smooth out any bubbles with a J-Roller. Remove and replace the flashing if necessary.
  7. Fold the flashing down onto the sheathing.
  8. Staple the flashing to the wall as necessary and seal the corner edges using 3/8″ staples.
  9. Next up, install the shimming support. Align the support on the sill, flush with the exterior and centred between the side jamb with at least 1/2″ on each side. Nail in place.
  10. Now your Rough Opening is prepared and ready to install your Window.

Contact us for additional information and complete written instructions specific to each window manufacturer. if you are having trouble with your window installation and would like a referral for an experienced Door & Window Contractor or Installer, we will happily refer you to a professional, or if you are thinking of replacing existing windows and would like some help, contact us via the button link below.

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