Flashing On Siding

Cut the drip cap to the correct size for your window.

Flashing on siding.

On a wall to be covered with wood cement board vinyl or metal. 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. And when those corners start to decay they become.

This has proven problematic over time as caulking the joint results in unsightly surface appearances due to the different textures as well as resulted in failure of the caulk joint and associated ongoing maintenance. 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. 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. It is always recommended to install step flashing behind stucco dryvit wood panel lap siding vinyl siding cedar shingle siding etc.

However in most instances step flashing should be installed behind siding. 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. Therefore the upper piece of wrap or flashing should always overlap any lower pieces. Attach the flashing tape above the window and then slip the drip cap into the siding and attach to the tape.

But unlike fiber cement siding wood is almost sure to rot. When it comes to flashing siding corners many builders simply use a 1x wood corner. 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. In certain instances flashing may need to be installed on the exterior of siding.