Flashing As Siding

You set flashing upon top edge of each piece of plywood over a fat bead of caulk and hold it in place with just heads of roofing nails driven into sheathing.

Flashing as siding.

With the flashing in place let s see what happens. Continue installing the z flashing at the top edge of the siding panels across the full length of wall. Galvanized z flashing so called because of its z shaped profile keeps water from getting through horizontal joints between sheets of plywood siding. The large leg of the metal goes against the wall leaving the seat and face covering the top edge of the 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. The water runs down the siding and at the bottom of the first row of vinyl siding it drips off and contacts the metal flashing as it runs across the top of the fascia board. But many builders fail to protect the most vulnerable areas of siding. The seat dimension 3 8 in corresponds to the siding thickness.

The water then runs off the flashing because it can t go up the flashing as it extends up behind the siding. It is used to protect the horizontal joints between sheets of siding from water infiltration. The best solution is a preformed or custom bent kick out flashing to divert the water away from the siding. Failed caulk joint with no flashing behind.

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. Otherwise dripping water will leave its mark along the siding. Galvanized steel z flashing is made from 28 gauge galvanized steel. Where the step flashing terminates along a sidewall is a common trouble spot for moisture problems.

The caulk has failed and water can find its way behind the siding. Flashing between brick and siding is a relatively similar process on all types of brick to siding transitions although there may be slight variations based on manufacturer recommendations. It requires no nails. Siding is the first line of defense against water intrusion and the multitude of problems it causes including the dreaded mold.

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. Depending on the reveal of your siding the flashing length will be inch less than the reveal.