In depreciating a home office, that office is supposed to be depreciated as commercial real property, which is MACRS straight-line over 39 years. Generally, §1250 property is depreciable real property (i.e., buildings and improvements) that is not subject to §1245. Now, a home office is "buildings and improvements". So, this home office nonresidential real property (in the MACRS 39-year class) is depreciable only under straight-line, this real property is not subject to recapture.

Yet, it has been my understanding that there is home office depreciation recapture, and many posts talk about matters surrounding this. But no one that I have seen explains why such depreciation recapture even exists, given the paragraph above. Please explain.