Flashing Around Windows and Doors

Window exploded viewHow to make sure your windows and doors are protected against the elements with flashing.

In many areas it is acceptable to simply install building wrap and pieces of drip-cap flashing over the tops of windows and doors. However, manufacturers and building codes often call for more elaborate flashings to protect the sheathing, studs, and interior walls. Whether you are installing new windows and doors or siding to existing units, plan and carefully install flashings that meet local codes and provide maximum protection against moisture.

The general principle is: As any moisture (which may collect due to condensation or small gaps in the siding) flows downward, it should not have an opportunity to infiltrate behind the house wrap where it can do damage. So the upper piece of wrap or flashing should go over any lower pieces.

The type and location of the flashings will vary depending on the type of windows and doors. If you have vinyl- or metal-flanged windows, for instance, you may install drip-cap flashing over the window itself or over the top trim piece that you install. For a wood unit, drip-cap flashing may be installed over the trim piece (often called brick molding) that comes with the window or door. Consult manufacturer's instructions for the recommended technique.

Horizontal sidingIn addition to metal flashing, self-adhesive flashings, similar to WSU sheets used for roofing edges, are often applied around window or door openings. If you are installing a new unit, the self-adhesive flashing will cover the inside of the framing as well as the sheathing. If the window already exists, the self-adhesive flashing will likely cover the sheathing and any window flanges only. In addition, self-adhesive flashing is sometimes installed at wall corners where it can be attached over the building wrap. Consult manufacturer's instructions, your local building department, or a professional siding installer who works in your area.

Installing a Window

When you install a window in new construction, the building wrap overlaps the self-adhesive flashing. In a remodeling job, a simpler arrangement is often used: Self-adhesive flashing strips are applied along the bottom, then the sides, then the top. Then small pieces of flashing are applied over the gaps at the corners.

Felt or Building Paper

In this arrangement, felt or building paper is first stapled to the sheathing, with the top pieces overlapping the lower pieces. A bead of caulk is applied to the felt, and the window is set in the caulk. Next comes another layer of building wrap, installed like the first layer. At the top, metal drip-cap flashing is tucked under the siding and on top of the second layer of wrap and the trim is installed just under the drip cap.

Patio Door

When sealing a patio door, follow manufacturer's instructions. In this arrangement, pieces of building paper and self-adhesive flashing are cut to fit and installed in the correct order so water has no chance to seep behind and damage the sheathing.

Source: www.diyadvice.com

General Electric General Electric GE012A Window and Door Silicone I Caulk, 9.8-Ounce, Clear
Home Improvement (General Electric)
  • Permanently weatherproof
  • 100% Silicone
  • Typical Uses: windows, doors, siding, trim, molding, baseboards, vents, around wires/pipes and other attic/basement applications
  • Adheres to: Most wood, metal, vinyl siding, drywall/plaster, glass and plastic
  • Meets federal specifications: TT-S-001543A (COM-NBS), TT-S-00230 (COM-NBS), ASTM-C-920 type S, NS, class 25 use NT, G A&O test requirements

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You would need to build out a proper sill

And frame around the opening. If the current siding is covering the window, you know there isn't one there.
You would want to wrap it in metal at least, then do your J-channel.
Sawzalling the siding and slapping some J-channel in place would let all manner of weather in behind the siding.
Then you have to consider why the windows were covered up in the first place. perhaps whoever did it wasn't completely incompetent/lazy. Maybe the windows are not weather-worthy.

Lexan will also be impacted by UV.

The plastic that will last the longest outside is PVC. Used for siding. Installers often have wide strips to make custom flashing around windows and doors.
Some aluminum flashing comes in rolls, 6, or 8 or 12" wide by maybe 20F long for pretty reasonable price at most lumber yards.
Many or most sheet metal shops could cut your size from either aluminum and stainless steel sheets
I often trade in scrap non ferrous junk for usable aluminum and stainless sheets at scrap yards.

Dap Dap 18152 Acrylic Latex Caulk with Silicone, 10.1-Ounce, White
Home Improvement (Dap)
  • Premium quality
  • Moisture and mildew resistant for caulking around window and door frames and siding corner joints
  • Provides excellent adhesion to glass, ceramic, wood, metal, brick, stone and more
  • 11 fl. oz
  • White
Ammex Corporation Momentive Performance Materials GE22681 Max Extra 3500 Siliconized Acrylic Window and Door Sealant, 10.1-Ounce, Almond
Home Improvement (Ammex Corporation)
  • For use around doors, windows, siding, trim, molding, baseboards and vents
  • Adheres to most metal, glass, tile, wood, metal, drywall, plaster, masonry and some plastics
  • Easy soap and water clean-up
  • For interior and exterior applications
  • Silicon zed acrylic
HEARTLAND HEARTLAND 21000 Dryer Vent Closure
Home Improvement (HEARTLAND)
  • Easy-to-install dryer vent closure
  • Lets warm air escape when open
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  • Vent must be installed vertically and sliding may need to cut for proper installation.

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  • Avatar Jeff Himself Are there any good restraunts around Cedar Point?
    Mar 03, 2010 by Jeff Himself | Posted in Other - United States

    We are staying at Breakers Express and we're wondering if there are any good local food spots around that area. Thank you!

    • Inside Breakers, You have:

      Tomo - Sit down restaurant featuring Hibachi Tables, Sushi Bar & Full Menu


      TGI Friday's® on the Beach - Jack Daniel's® Grill, Friday's Favor …onal & Franchised

      Cracker Barrel
      4216 Milan Road • Sandusky, OH 44870

      T.G.I. Friday's
      2003 Cleveland Road • Sandusky, OH 44870