It is important to keep in mind, however, that the approximate square footage of an apartment is often just that – an approximation.
Different appraisers or professionals may use different methods or standards in coming up with their square footage figures. Some will determine square footage of an apartment by measuring the space between the interior walls, including bathrooms, closets and foyers, while others may use exterior walls or other benchmarks. Some will include unusable floor area such as columns, mechanical pipe shafts and chases in their calculations.
Moreover, many Manhattan apartments, including pre-war buildings, often have hard-to-measure elements like oddly shaped rooms, removed walls, or even turrets or alcoves. This is especially true for many of New York City’s oldest and most prestigious residences.
In addition, while many cooperative apartment buildings may have filed floor plans with the Attorney General’s office as part of their offering plans, those floor plans may not be up to date. Condominium offering plans also include floor plans and measurements, but developers often use different methods for measuring the square footage of their respective units. For example, some will include hallways or foyers or bathrooms in their square footage figures, others will not.
Offering plans will only tell you the approximate square footage and the method used to measure it by the developer at the time of construction or conversion. Plans will not tell you how the square footage is measured at the time of a resale.
All potential purchasers should be made aware that all square footage measurements that are provided by brokers are usually just estimates, and are not certified or deemed reliable by either the listing firm or a participating co-broker. In addition, a buyer determined to have a square footage measurement should consult or retain their own professional, and have that professional explain the methodology for the measurement.
0riginally posted November 2010