I should have mentioned Tracy's thorough review on "the other site" of Trumpeter's HMS Royal Oak, in which he acknowledged the wood planking on the shelter deck piece and stated that on the ship it was, in fact, covered in steel plates. I have found Google AI to be accurate in helpful with many arcane questions on numerous topics, so arbitrarily built my Royal Oak model with a corticine-colored shelter deck. A shame, in a way, since the aftermarket wood deck I had purchased included a beautifully fashioned wood shelter deck, which I had to remove when re-reading Tracy's review. Given his extensive knowledge of this subject (and access to published references), I yield my decision to his wisdom!