Are your siding nails inset within the siding boards themselves, like those pictured here? If so, it’s either because (a) the nails were overdriven or more likely (b) the siding is swelling and expanding with moisture. Inset nails need to be sealed to prevent moisture intrusion which can lead to deterioration. For siding discovered at this home inspection in Freeland on Whidbey Island, substantially swelled/deteriorated siding needed to be replaced.
