Can my metal garage be attached to an existing structure? Follow Our garages can attach to any building, including a home. You will just be purchasing three walls instead of four! Related articles How much does a metal garage cost? Is it cheaper to build an attached or detached garage? Will General Steel refer me to a local erector or contractor? How much does it cost to build a steel workshop? Can I have a two-story barndominium? Comments 0 comments Please sign in to leave a comment.