It is always recommended to install step flashing behind stucco dryvit wood panel lap siding vinyl siding cedar shingle siding etc.
Flashing for wood siding.
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.
Siding nails should not be caulked another item that needs room to play is siding boards themselves.
When it comes to flashing siding corners many builders simply use a 1x wood corner.
Also avoid caulking tongue and groove siding boards together.
Otherwise dripping water will leave its mark along the siding.
The large leg of the metal goes against the wall leaving the seat and face covering the top edge of the siding.
Galvanized steel z flashing is made from 28 gauge galvanized steel.
But unlike fiber cement siding wood is almost sure to rot.
Add felt if needed before nailing the new wood on and prime the new wood on all four sides before installing it.
Metal flashing or any metal to wood joint should not be caulked another water exit pathway that should never be sealed.
However in most instances step flashing should be installed behind siding.
And when those corners start to decay they become.
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.
In certain instances flashing may need to be installed on the exterior of siding.
Where the step flashing terminates along a sidewall is a common trouble spot for moisture problems.
Wood siding flashing details at joints corners.
Continue installing the z flashing at the top edge of the siding panels across the full length of wall.
This article series discusses best practices construction details for building exteriors including water and air barriers building flashing products installation wood siding material choices installation vinyl siding stucco exteriors building trim exterior caulks and sealants.
The best solution is a preformed or custom bent kick out flashing to divert the water away from the siding.
The nails holding up the siding should not be caulked.
Install the kickout flashing underneath the first shingle photo 1.
It is used to protect the horizontal joints between sheets of siding from water infiltration.
The seat dimension 3 8 in corresponds to the siding thickness.
The type and location of the flashings will vary depending on the type of windows and doors.
