The Roman house
An atrium house after Vitruvius VI.3: fauces, atrium with compluvium and impluvium, alae, tablinum and peristyle, proportioned from the atrium width.
The rules it illustrates
Three proportions for the atrium. Give the atrium one of three shapes: width to length as 3 : 5, or 2 : 3, or a length equal to the diagonal of the square on the width; and make its height to the girders a quarter less than its width.
Alae, tablinum and fauces from the atrium. Proportion the rooms round the atrium from it: the alae from its length (a third for atria of 30–40 feet, a quarter for 50–60), the tablinum from its width (two-thirds for a 20-foot atrium, half for 30–40 feet, two-fifths for 40–60), and the entrance passage from the tablinum.
The opening in the roof. Leave an opening in the atrium roof not less than a quarter nor more than a third of the atrium’s width, with a length in proportion; beneath it set a basin to receive the rain.
The peristyle garden. Make the peristyle a third longer across than it is deep, its columns as high as the colonnades are wide, and the spaces between them not less than three nor more than four diameters.
Where it appears in the book
In the styles Ancient Roman.
In the chapters The Classical World.