2001 Housing Census: features and innovations

Roberta Vivio ()

Istat, Direzione Centrale Censimenti della Popolazione e Territorio.

The 2001 Italian Housing Census presents some innovations and specific features, in comparison with the previous census, as a consequences of several inputs: the international guidelines[1], a review of the 1991 census results, an overview of other countries housing censuses, and the analysis of the changing social context. Still the maximum of comparability with 1991 census has been preserved, as a primary prerequisite.

The main innovations are related to 1- observation units and their definitions, 2- the enumeration rules.

As regards point 1, a new observation object has been introduced, namely the building. Jet in 1981 and 1991 housing censuses some information on buildings were collected within the housing questionnaire. But no information was collected and no enumeration was carried out on non-residential buildings. In the 2001 census the building itself is an observation unit and is enumerated with a separated and independent questionnaire, filled in by the enumerator, and linked to the family questionnaires through a unique key-code. The building enumeration is the completeness of the population census, as it collects a complete set of information on residential buildings, but it collects a minimum set of information on non-residential building. Among the former kind of observation unit there is also the so called “complex of buildings”, that allows to take into account and geo-reference a special and articulated kind of non-residential constructions (like in some cases are hospitals, universities, industries, and several other typologies). New and additional information, in comparison with 1991 census, are available for each building: the type of building (residential, school, hotel, industrial, church, communication and transport, etc…), the number of stairs, the state of conservation, and a couple of control-questions on the source of information.

As regards the observation units of the dwelling census, a new definition of “occupied dwelling” has been adopted; the new definition still allows for comparison with 1991 census, but it is an easier one for families and enumerators to understand, and more intuitive to anyone. An occupied dwelling is now the one that contains a person at the census conventional date (21 october 2001), regardless of official residence of the person present in the dwelling (while in 1991 an occupied dwelling was only the one occupied by officially residents families). For occupied dwelling the complete set of questions has to be answered, while only a sub set of variables has to be answered in the case of non occupied dwellings. Some new questions have been added: whether structural and non-structural works have been carried out in the dwelling in the past ten years, whether a private car-parking is available, whether a cooking corner (and not only a “traditional kitchen”) is available.

As regards point 2, no changes have been performed on the dwelling enumeration plan. On the contrary, the building enumeration requires different rules according to the territory: very simply we can say that in “urban” areas the building enumeration is the most complete (all buildings are taken in account), while in “non-urban” areas only residential building are considered. This approach permit not to burden too much the enumeration operations and the enumerator work, and it follows the approach that states the building enumeration as the completeness of the population census.

Thanks to the link among families, dwellings and buildings (through the key-code) it will be possible for the first time in Italy to give a multi-dimensional description of human settlements. In fact, in spite of the existence of a construction public register (called “catasto”) in Italy, it is not possible to link the information of the register with those of censuses, because of different definitions, aims and rules that characterise the two sources of data.

Francovich:- VIVIO_Eurostat_2002_ita.doc

[1]United Nations, Economic Commission for Europe, «Recommendations for the 2000 censuses of population and housing in the ECE region».