VI.5 Vacant Street Frontages and Pseudo-Addresses

‘Real’ addresses are officially assigned to new buildings by the topographic bureaus at each of the five borough president’s offices. In addition, GSS assigns addresses called pseudo-addresses to some vacant street frontages of tax lots, that is, to street frontages that do not have ‘real’ building addresses. Pseudo-addresses have no ‘official’ status; they are not meaningful outside of the Geosupport System and should not be used for any operational purpose. In particular, mail sent to a pseudo-address is likely to be undeliverable. Since pseudo-addresses are not associated with buildings, they do not have associated BINs. Note: Pseudo-addresses are not to be confused with the unrelated concept of pseudo-street names (discussed in Chapter III.6).

When assigning a pseudo-address, GSS attempts to anticipate what ‘real’ address might someday be assigned to a building if one were to be built at that location. However, the assignment of pseudo-addresses can sometimes involve an element of arbitrariness, especially where there is a wide gap between the two real addresses that ‘sandwich’ a vacant frontage, or where there is a row of several adjacent vacant frontages. When assigning a pseudo-address, at a minimum, GSS uses a house number that is not already in service on the given street and that is in proper sequence with nearby real house numbers and with any previously assigned pseudo-addresses. If no such house number is available, no pseudo-address is assigned to that vacant street frontage.
Function 1A is designed to accept as input both real addresses and pseudo-addresses. Also, both Function 1A and Function BL include pseudo-addresses in the list of geographic identifiers that they return for a tax lot Pseudo-addresses serve the following purpose: Certain information is obtainable from Geosupport by address but not by BBL, such as many political and administrative district identifiers that Functions 1 and 1E return. For vacant tax lots, which have no buildings at all and therefore no real addresses, pseudo-addresses provide the only means to obtain such information from Geosupport. Of course, for those vacant tax lots that have no pseudo-addresses assigned to them, it is not possible to obtain such information from Geosupport.

If a pseudo-address comes to be assigned as a real address of a newly constructed building, GSS changes that address’s classification in the Geosupport System from pseudo-address to real address. At the same time, the address’s tax lot might also change, if the new building happens to be on a different tax lot than the lot to which the address had been assigned as a pseudo-address. Real addresses can also change status and become either Geosupport rejects or pseudo-addresses, as the result of building demolitions. Geosupport is updated to reflect such changes, but time lags are possible.