siding vs building material

siding and building material both are nouns.

Word	Noun	Adjective	Verb	Adverb
siding	Yes	No	No	No
building material	Yes	No	No	No

As nouns, building material is a hypernym of siding; that is, building material is a word with a broader meaning than siding:

siding: material applied to the outside of a building to make it weatherproof
building material: material used for constructing buildings

siding (noun)	building material (noun)
a short stretch of railroad track used to store rolling stock or enable trains on the same line to pass	material used for constructing buildings
material applied to the outside of a building to make it weatherproof