Barrier lapped the right way
Every upper course over the one below, seams taped. Reversed laps funnel water inward and they are a regular find on walls that have been clad twice.
Siding
Siding Repair and Replacement in Pine Hill, NJ
The visible layer sheds most of the rain. What stops the remainder reaching the structure is underneath it, and that is where a siding job is won or lost.
Cladding sheds, the barrier stops
Horizontal siding is not watertight and was never meant to be. It throws off the bulk of the rain and lets the rest run down the back face, where a weather barrier and the metal at each opening are supposed to carry it out again. Put new cladding over a barrier that is lapped the wrong way, or over an opening with no pan beneath it, and the wall is in exactly the condition it was in before, with a tidier front. The work worth paying for happens in the hour after the old cladding comes off.
What gets done once the wall is open
Pans and head flashing at every opening
Metal above and a pan below, with the wrap cut and folded in sequence. Most leaks blamed on cladding start at one of these three details.
Kick-outs where a roof dies into a wall
The small angled piece at the bottom of a slope-to-wall junction. Omit it and every rainfall pours behind the cladding at that exact point.
Sheathing cut out where it is soft
Checked with the wall open and replaced where needed, at a rate that is already on the estimate rather than discovered later.
Repair where repair will hold
A single face knocked about by a storm, or soft board beneath an outlet that has been dripping for years, will frequently come good on its own without touching the other three elevations. You get that answer at no charge as well.
Why the roofer should handle it
Where a slope runs into a wall, the detail sits across two trades and so, in practice, under nobody's name. Its metal has to tuck behind the boards and sit on top of the shingle, which means correcting it is work on both at once. Putting one crew's name against the whole thing ends the question of which company's work the water came through — the question homeowners least want to be standing in the middle of.
Find out what is behind the cladding
The wall and the roof edge above it looked at together, photographed and written up, free.