Navy for floor, a deck is primarily a horizontal surface, not to be confused with a flat, which is a table or desk top. When you first enter boot camp your Company Commander will tell you to hit the floor and give him 50. Of course there is no floor any longer, there is only a deck. If anyone drops to give him 50, everyone is in trouble. We figured that one out pretty quickly.

Here is some pretty boring stuff about decks that probably nobody except and engineer would care about. All the following engineering speak is from Wikipedia.

The thickness of the decking affects how strong the hull is, and is directly related to how thick the skin of the hull itself is, which is of course related to how large the vessel is, the kind of work it is expected to do, and the kind of weather it may reasonably be expected to endure. While a Naval Engineer or Architect may have precise methods of determining what the scantlings should be, traditional builders used previous experiences and simpler rules-of-thumb to determine how thick the deck should be built.

The numbers derived by these formulae gives a rough number for determining the average thickness of materials based on some crude hull measurements. Below the waterline the thickness should be approximately 115% of the result, while upper topsides and decks might be reduced to 85% of the result.

• In wood - For plank thickness in inches, LOA (Length Overall) and Beam are measured in feet. For plank thickness in mm, LOA and Beam are measured in meters.

o Plank thickness in inches = (Square root of LOA+Beam)/16

o Plank thickness in mm = (Square root of LOA x 3.28 + (beam x 3.28) x 1.58

• In fiberglass - For skin thickness in inches, LWL (Length Waterline) is in feet. For skin thickness in mm, LWL is in meters.

o Skin thickness (inches) = 0.07+(LWL/150)

o Skin thickness (mm) = 1.8 + (LWL/1.8)

• In fiberglass sandwich - First determine the skin thickness as single skin and then multiply by modifiers for inner skin, outer skin, and core thicknesses. Cored decks might be modified even thicker, 2.6-2.7, to increase stiffness.

o Inner skin modifier = 0.3

o Outer skin modifier = 0.4

o Core modifier = 2.2


Now if that doesn’t give you a head ache then I am not sure what will. Like I said, unless you are designing a ship you never give that information any thought. But the decks on a Navy ship are very important, they must support a great deal of weight while using a minimum of support steel. That is another reason the navy has gone to Gas turbines, less weight and less equipment needed to support them as compared to a boiler.

We as civilians use deck a good deal of time. I hear non sailors talk about hitting the deck or dropping a tool on the deck. It seems maybe there is a little bit of sailor in all of us.