Water Getting In After Having Siding Installed

Inspect the area above the leak including both indoors and out.

Water getting in after having siding installed.

The shingles should be hanging about 1 4 inch to 1 2 inch beyond the drip edge so this may be your problem. Water runs down the siding and can collect in the j channel. Water or moisture enters fiber cement siding possibly water leaking into the wall behind siding but unlikely through improperly located too close in successive courses butt joints. Water should not be allowed to run down the siding.

It can get behind the siding and cause serious problems within the walls as well as leakage in the basement or crawl space. Use a caulking gun to apply a continuous bead of silicone sealant along the vertical seams between the vinyl j channels and the exterior window casings. Usually the head lap and tightly butted end joints avoids this trouble. Rainwater leaking from a gutter ends up behind siding and causes a wall to rot.

This is most prominent in j channels that run horizontally such as trim running along a window frame. Water that blows into cracks between siding pieces can be absorbed into structural wood and insulation where it may stay and grow mold or rot wood siding from behind. Building leaks behind installed siding at improperly flashed butt joints. Openings at the lap joints of vinyl siding sections as well as drain openings provided along the bottom edge of most vinyl siding products let the wall system breathe and allow wind blown rain that may enter the siding to drain out of it as well.

Check to be sure weep holes are open along bottom of window openings. At some point in the past an owner had vinyl siding installed over old siding. Although vinyl is impervious to water when installed as directed by the manufacturer vinyl siding as a whole is not completely watertight.