Позволявам си да го преведа по този начин, тъй като в конкретния текст фразата следва да се разбира като коментар на цялостния изглед като архитектурна проекция на преобладаващата ориентация в разположението на отделните части (сградата е решена визуално в хоризонтален, а не във вертикален план).

disposition =

d. Arch., etc. The due arrangement of the several parts of a building, esp. in reference to the general design: see quots.
1624 Wotton Archit. (1672) 14, I may now proceed to the Disposition thereof [i.e. of the matter], which must form the Work. 1706 Phillips (ed. Kersey), Disposition+in Architecture, is the just placing of all the several Parts of a Building, according to their proper Order. c1850 Rudim. Navig. (Weale) 115 Disposition; a draught or drawing representing the several timbers that compose the frame of the ship, so that they may be properly disposed with respect to the ports, &c. 1876 Gwilt Encycl. Archit. Gloss., Disposition, one of the essentials of architecture. It is the arrangement of the whole design by means of ichnography (plan), orthography (section and elevation), and scenography (perspective view). 1886 Willis & Clark Cambridge III. 247 The general inclosure within walls, the disposition into courts+all have their analogies+in the monastic buildings.

as defined in OED .

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Note added at 4 days (2008-04-22 08:28:50 GMT) Post-grading
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Благодаря за избора!