However in most instances step flashing should be installed behind siding.
Flashing on siding.
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.
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.
Position the flashing lengths as defined in step 2 overlapping the ends a minimum of 2 inches onto the previous flashing piece and securing the flashing with 8d nails at each wall stud.
The large leg of the metal goes against the wall leaving the seat and face covering the top edge of the siding.
Inspect the sidewall around and underneath the fascia and inside the house for signs of moisture damage and repair any rotted areas.
Galvanized steel z flashing is made from 28 gauge galvanized galvanized steel z flashing is made from 28 gauge galvanized steel.
This tends to be easiest with lap or panel siding cladding types that can be removed and re installed by unscrewing fasteners and most difficult with brick and stucco claddings that require materials to be chipped out and replaced.
On a wall to be covered with wood cement board vinyl or metal siding the step flashing and associated roofing must be installed first so the siding can cover the top of the step flashing on.
In certain instances flashing may need to be installed on the exterior of siding.
If the kick out and step flashing can t tuck behind the siding screw on cap flashing to cover it then caulk along the top.
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.
Retrofitting to add base flashing involves removing a portion of the cladding at the bottom of exterior walls.
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.
Continue installing the z flashing at the top edge of the siding panels across the full length of wall.
Therefore the upper piece of wrap or flashing should always overlap any lower pieces.
Add felt if needed before nailing the new wood on and prime the new wood on all.
Inside corner w flashing.
It is always recommended to install step flashing behind stucco dryvit wood panel lap siding vinyl siding cedar shingle siding etc.
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.
