Does a shed, pool house, or outbuilding count as square footage?
Published August 27, 2026
No. Sheds, pool houses, workshops, barns, and any other detached building are separate structures under ANSI Z765 and are never added to the house's gross living area, even when fully finished, heated, and plumbed. They are described and valued on their own as site improvements or accessory buildings.
Finished pool houses and studios
A finished pool house with a bath is valued as an accessory building, and if it has a kitchen it may be an ADU. Either way it is measured separately. A backyard office pod is the same.
How the appraisal shows it
Outbuildings appear in the site or improvements description with their size and condition, and get a lump-sum adjustment against comparable sales that lack them. A basic shed adds far less than a finished studio with power and plumbing, but neither one is GLA.
The one way an outbuilding joins the house is an enclosed, finished connector. An enclosed, finished breezeway is the one thing that can change that.