Even if the roof has been properly flashed against the sidewall this one hasn t water can still run down the side of the house and behind the siding causing rot.
Flashing on siding.
Using a pry bar you will need to remove a layer of siding from above the window you want to install the drip cap on.
Use a felt paper spline wrapped around the corner and extending 6 inches beyond the corner board to protect the joints where the siding meets the corner boards see figure 1 5 at left.
Use an old rag to remove any dirt or debris that may be there.
Flashing helps prevent any moisture which can collect due to condensation or small gaps in the siding that flows downward from infiltrating behind the house wrap where it can do damage.
However in most instances step flashing should be installed behind siding.
In certain instances flashing may need to be installed on the exterior of siding.
Flashing is a strip of metal usually aluminum about 8 inches long and bent at 90 degrees with each side at least 5 inches wide.
The solution to rotting sidewalls is a small piece of bent metal called a kickout flashing at roofing suppliers which simply directs all that water away from the wall.
But unlike fiber cement siding wood is almost sure to rot.
Cut the drip cap to the correct size for your window.
When it comes to flashing siding corners many builders simply use a 1x wood corner.
Building siding flashing finish details for building corners use overlapping 1x4s or 1x6s at outside corners or use 5 4 stock for a heavier look.
On a wall to be covered with wood cement board vinyl or metal.
A common problem with cement board siding products and some other types of horizontal lap siding is that older installation guidelines called for caulking the joint instead of flashing the joint.
It is always recommended to install step flashing behind stucco dryvit wood panel lap siding vinyl siding cedar shingle siding etc.
Therefore the upper piece of wrap or flashing should always overlap any lower pieces.