Can Large Skylights Qualify as Ceiling Pockets?

In NFPA 13 2019, Section 10.2.9, designers can omit sprinklers from inside ceiling pockets as long as their construction is less than 1,000 cubic feet of non- or limited-combustible material, their depth is shallower than 36 inches, and the entire floor below them is sprinklered with quick-response sprinklers.

For instance, a 15x10 pocket ceiling of 2 feet depth with quick response sprinklers in the surrounding ceiling and of non-combustible construction is allowable.

For a skylight less than 32 square feet and any depth, designers can omit sprinklers per Section 9.3.16. Additionally, an unlimited number of such 32 square foot skylights are permitted without additional sprinklers, provided that they are at least 10 feet from the nearest skylight or ceiling pocket.

There is ambiguity, however, if a skylight exceeds 32 square feet.

What is the guidance on shallow skylights?

Where are skylights defined, either as in the category of ceiling pockets or distinct from ceiling pockets?

​If there is a 15x10 skylight with a 2-foot depth and non-combustible surrounding construction, would it be different from an equivalent ceiling pocket in terms of sprinkler activation?

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