Area is US Pacific NW (Portland, OR)
My recently purchased home (built 1972) has clapboard siding made of (I've been told) Masonite, probably 10-15 years old. When it was installed the painters painted under the butt edges only where it was easy to get to, i.e. knee high and above, and did not paint under the bottom two courses. This has resulted in some water damage over the years.
See below for pictures.
I'm not in a position to replace the siding or do major repairs, but would like to prevent or at least slow down further damage by sealing the unprotected butt edges.
I am considering applying a clear paintable silicone caulk to the underside of the butt edges on the lower two courses, and any other butt edges that are incompletely painted. Would this work, or should I be doing something different?
Wide shot of the siding
Butt edge about 6' up. It is mostly painted but even this one could use some sealing
Bottom course, this is the worst of it.
Bottom course with less swelling/damage.