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EXPOSITION AT VIENNA.
11. Every house shall he provided with a wall at least six inches thick, separating it from its neighbor,—for the two houses thus ensues a wall of twelve inches.
The thickness of walls must be regulated by the weight they have to support and the material of which they are composed ; also by the height of the stories and the construction of the floors and ceilings.
O
The following rules are to be observed :—
(a.) The principal outer walls, as well as all interior walls, at the point where they contain flues, must be at least eighteen inches thick. The principal walls of the upper story must be at least two feet thick, if the depth of the rooms is more than twenty feet. The main walls may have the same thickness in two successive stories. In buildings of three stories, the main walls must, at the ground, be at least two feet thick; in buildings of four stories, at least two and one- half feet thick. Those portions of the main w r alls which do not support floors can be made eighteen inches thick for all stories.
(b.) "Where the ceilings are vaulted and rest on iron girders, in case the latter are not more than twenty feet long, the walls supporting them need only be eighteen inches thick for all stories; where they are of greater length, the walls must be two feet thick.
(c.) The foundation walls must, in all cases, be six inches thicker than those of the lower story.
(cl.) In light walls, the walls must be in all cases eighteen inches thick where they support ceilings or bound rooms used for dwelling purposes. In other cases they need be only twelve inches thick.
(e.) "Walls supporting massive floorings of half or whole trees (as described) must be two feet thick, and the trees must rest for six inches at their ends upon the same.
The thickness of walls, as seen by the above extracts from the laws, is flxed in no case at more than three feet, which would occur in foundations where the basement wall had two and a half feet. The Austrian foot is about one-half inch