The 8 inch height prevents water from pouring over the top of the flashings into the building or system.
Step flashing at roof height.
Step flashing step flashing redirects the water back onto the shingle.
Posted march 4 2017 filed under roof installation roof repair maintenance.
Second step flashing needs to extend 8 to 14 inches above the shingles according to the national roofing contractors association nrca.
Once complete the housewrap should overlap the step flashing that s applied to the wall.
One side of the l shape lays under the shingle and the other side attaches to the side of the wall.
The vertical side will be hidden behind the exterior wall covering material.
Vertical flashings must be a minimum of 8 inches above the completed roof surface.
If this is a repair job the siding must also be removed and replaced with the flashing.
Continuous flashing against a sidewall is one way to install a roof but it s not the correct way.
This height has become the industry standard and is recognized by most membrane manufacturers.
Step flashing if made of metal should be galvanized steel at least 0 019 inches thick irc 2015.
Step flashing is used where a roof meets a wall to cover the junction of those elements preventing leaks.
Flashing is a strip of metal usually aluminum about 8 inches long and bent at 90.
This flashing is typically field fabricated from a sheet of 26 ga.
Bent into an l shape.
Even if one piece of step flashing fails the flashing and shingle below it start the process over again.
How to install roof flashing against a wall.
This layer is called the step flashing.
Step flashing should be extended at least 4 inches up the wall from the roof deck and at least 4 inches out along the roof deck 2015 international residential code irc.
Manufacturers requirements can vary anywhere from 2 inches to 10 inches and you probably won t be able to see the sidewall flashing completely anyway.
Next l shaped pieces of metal typically aluminum are placed under each shingle that butts up against the vertical wall.
Roof felt should be installed prior to installing the step and kick out flashing.
Galvanized sheet metal bent at a 90 degree angle i e.
Step flashing needs to turn up a minimum of three inches up the sidewall.
Step flashing should be integrated with the drainage plane above for example overlap housewrap over it.
Step flashing is used to provide a water tight connection where roofing adjoins a vertical juncture.
This membrane attaches up the side of the wall as well.
Step flashing size requirements vary according to manufacturer.