Restrictive clauses are essential for the meaning of a sentence and are never separated from the rest of the sentence using commas, unlike the nonrestrictive ones.
The sentences that contain a restrictive clause are 1 and 3.
Because in sentence 1, The writer stated "That we found in the shed".
Also in sentence 3, The writer stated "That I grew up in".
These are important to in order to understand the whole sentence and cannot be deleted.
