One way to give a functional nod to nautical is with a rope stair railing and rope bannister.
This staircase by Jonathan Adler not only has a rope railing, but also a graduating blue for the front of the steps to enhance the nautical appeal.
Nautical staircase with rope railing in a Florida cottage featured on Southern Living. They removed the stairwell spindles and replaced them with Hearty Manila Rope.
This Staircase leads to a home gym over a garage. Window hardware from Restoration Hardware was used to install this rope stair railing.
I think thick rope is the way to go, white or natural, depending on the look and feel you want. Via Laurie's Projects.
Heavy duty rope stair railing in Thom Filicia's House featured in House Beautiful.
And go to House and Home for this DIY Nautical Rope Railing.
Not a fan of the loose rope railing? Try this idea by C Design. A creative rope bannister design idea that includes Nautical Boat Cleats.
A custom built curved staircase with a rope railing detail. Seen in a New Jersey Shore Cottage.