Bel étage

The piano nobile (Italian, "noble floor" or "noble level", also sometimes referred to by the corresponding French term, bel étage) is the principal floor of a large house, usually built in one of the styles of Classical Renaissance architecture. This floor contains the principal reception and bedrooms of the house.

The piano nobile is often the first (European terminology, second floor in US terms) or sometimes the second storey, located above a ground floor (often rusticated) containing minor rooms and service rooms. The reasons for this were so the rooms would have finer views, and more practically to avoid the dampness and odours of the street level. This is especially true in Venice where the piano nobile of the many palazzi is especially obvious from the exterior by virtue of its larger windows and balconies and open loggias. Examples of this are Ca' Foscari, Ca' d'Oro, Ca' Vendramin Calergi, and Palazzo Barbarigo.

Larger windows than those on other floors are usually the most obvious feature of the piano nobile. Often in England and Italy the piano nobile is reached by an ornate outer staircase, which negated the need for the inhabitants of this floor to enter the house by the servant's floor below. Kedleston Hall is an example of this in England, as is Villa Capra in Italy.

Most houses contained a secondary floor above the piano nobile which contained more intimate withdrawing and bedrooms for private use by the family of the house when no honoured guests were present. Above this floor would often be an attic floor containing staff bedrooms.

In Italy, especially in Venetian palazzi, the floor above the piano nobile is sometimes referred to as the "secondo piano nobile" (second principal floor), especially if the loggias and balconies reflect those below on a slightly smaller scale. In these instances, occasionally in museums etc., the principal piano nobile is described as the "primo piano nobile" to differentiate it. Though often found, this usage is potentially misleading: rooms in the (primo) piano nobile are always the grandest, less so those in the secondo piano nobile (which is indeed 'secondary'). The term is not used in Britain.

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Wikipedia