Why didn't the inspector check the roof on my condo?

Because you do not own it, and the standard of practice says so in writing. InterNACHI's Scope of Condominium Inspection Clause states that the inspector will inspect only the condominium unit, that the inspection will not include any inspection of common areas or other spaces the client does not own, and that components which are not the property of the seller will not be inspected — naming specifically the roof of a condominium or townhouse, exterior stairs, pools, railings, stucco, decks and common-area items. ASHI's standard reaches the same place from the other direction: under its general exclusions the inspector is not required to inspect common elements and common areas in multi-unit housing, such as condominium properties and cooperative housing. So the exclusion is not an inspector cutting the job short. It is the scope of the engagement, and it follows the ownership line your declaration draws. What we will do is tell you what is observable anyway, as a courtesy comment outside the required scope: the roof's apparent condition from the ground, staining at the ceiling of a top-floor unit that suggests envelope or roof leakage, visible exterior repair underway, and the condition of balconies, decks and guards you use even if you do not maintain them. Those observations carry real weight, because a component you do not own is still a component you help pay to replace. The other half of the answer is where the roof question actually gets settled: the reserve study. That document states the roof's age, its expected remaining life and whether the association has funded its replacement, and it is the only thing that will tell you whether you are buying into a roof replacement. Ask for it, along with the assessment history and recent board minutes, during your document-review period. We will flag what the condition suggests; the documents tell you who pays.