Loud Crack Sound at Night
I was wondering if this sound I hear in the evenings is normal. I live on a wood/epoxy/glass composite sailboat with a fiberglass deck in Seattle, and nearly every night I'll hear a single loud crack coming from the direction of either the deck, the side hull, or the window housing (it's a single large sheet of poly-something adhered and bolted in place).
My guess is that it has to do with the expansion and contraction of one of these components as the day cools off, but it's loud enough to be startling and a little worrisome. Do other folks experience this? Should I worry about the wood cracking or some other kind of separation taking place?