How to Roof Eave Flashing Guide??

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1.  What is Eave Flashing and Why It MattersThe eave is the lower edge of a roof that overhangs the wall.  Flashing is a thin weatherproof metal or composite strip that is installed along the eave to  Purpose  What it prevents  Where it goes  Water barrier  Infiltration through gaps between shingles ridge and siding  Along the underside of the eave between the roof deck and the wall plate  Air seal  Moisture and wind from entering the wall cavity  Over the eave extending down the wall a few inchesWhen flashing fails the eave becomes a fountain of water leading to rot mold and compromised structural integrity.2.  Common Types of Eave Flashing  Flashing Type  Typical Material  Best Use Case  Standard Metal Aluminum or Galvalume  12mm thick sheet  Most residential roofs easy to cut and shape  Modified Bitumen  Bitumenimpregnated felt jointed to metal  Flat or lowsloped eaves where metal may be hard to install  Engineered Flashing Preformed  Composite or metal with integrated vents  Roofs with complex angles or where a seamless fit is needed  SFlashing  Aluminum or steel shaped like an S  Wraps around the eave and extends down the wall providing a double layer  TFlashing  Tshaped metal  Used for the T point where the eave meets the wall plate  IceandWater Shield IWS  Thick selfadhesive bitumen  For eaves in freezethaw climates adds extra waterproofing  Copper Flashing  Copper sheets  Luxury or historic roofing where corrosion resistance amp aesthetics matter3.  How to Install Eave Flashing  StepbyStep  Tools amp Materials Needed  - Flashing choose type above  - Roofing cement or sealant  - Utility knife and tin snips  - Caulking gun for bitumen or sealant  - Roofing nails or staples appropriate size  - Safety gear helmet harness gloves eye protection3.1  PreparationInspect the Roof Deck  Clean any debris old shingles or loose material.Measure the Eave Length  Add a few extra inches for overlap.Mark the Cut Line  On the flashing mark where it will be cut to fit the eave width  overlap.Cut the Flashing  Use a tin snip and a utility knife to get a clean edge.3.2  Installing the Base Layer Metal or BitumenPlace the Flashing Over the Eave  The flashing should sit on top of the existing shingles or under the new ones covering the eave fully.Secure It Metal Hammer roofing nails at intervals usually 812inches apart.Bitumen Apply a bead of roofing cement along the bottom edge and press the flashing down.Seal the Edges  Use roofing cement or a highquality sealant to fill any gaps between flashing and shingles.3.3  Adding the Secondary Layer SFlash or TFlashPosition the Secondary Flashing  Overlap the first layer by at least 2inches.Nail or Staple  Secure it in the same manner as the first layer.Seal the Overlap  Apply a bead of sealant at the seam.3.4  Finishing TouchesCheck for Gaps  Inspect the entire eave for any missing nail heads or sealant.Seal the Wall Plate  Apply a bead of sealant around the bottom edge where the flashing meets the wall.Install a Gutter Optional  See 5 for a comparison with gutters.4.  Protecting Your Roof by Flashing  Threat  Flashing Solution  How It Helps  Water infiltration into wall cavity  Doublelayer Sflashing amp IWS  Creates a continuous barrier that diverts water downwards  Ice damming in cold climates  IceandWater Shield  insulated eave  Prevents meltwater from refreezing at the eave  Windborne debris  Metal flashing with a slight overhang  Stops debris from blowing under shingles  Heat loss in winter  Flashing with insulated backing  Reduces thermal bridging at the eaveMaintenance TipsInspect annually for rust sagging or missing sealant.Replace any damaged flashing immediately to avoid leaks.Keep gutters clear of debris to reduce pressure on eave flashing.5.  Flashing vs. Gutter  Which Does What  Feature  Flashing  Gutter  Primary Function  Seals and waterproofs the roof edge  Channels water off the roof  Material  Metal bitumen composite  Metal PVC aluminum copper  Installation Zone  At the eave on the roof deck  Along the eave line on the ground  Interaction  Works with gutter to keep the transition point dry  Works with flashing to prevent water from seeping into the flashing  Water Path  Diverts water downward along the flashing  Conducts water to downspouts  Typical Lifespan  2030yrs metal 1020yrs bitumen  1525yrs metal 1015yrs PVC  Maintenance  Inspect for rust sealant damage  Clean debris check for sag or leaksBottom Line- Flashings keep the edge of the roof dry by sealing the junction between roof deck and wall.- Gutters keep the water from pooling on the roof surface and direct it safely away.Both are essential and they complement rather than replace each other.6.  Quick Reference Checklist  Task  Frequency  Notes  Inspect flashing for cracks or rust  Semiannually spring amp fall  Use a flashlight at night look for water streaks  Check sealant amp caulking  Annually  Reapply if cracked or missing  Clean gutters  Every 24 weeks after rain  Prevents backpressure on flashing  Replace damaged shingles  As needed  Avoid letting shredded shingles sit on flashing  Apply sealant to eave  Every 57yrs  Especially in heavy rain or freezethaw zonesFinal ThoughtThink of eave flashing as the roofs safety netit intercepts water before it can breach the wall.  By installing proper flashing and keeping gutters clean you give your roof a second skin that can last decades.  When in doubt hire a licensed roofer a wellinstalled flash wont cost as much in the long run as a repair after a leak has taken hold.

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