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Perimeter Beams

Opening context:
Box Columns, Floor-Ceiling Vaults, Floor and Ceiling Layout

Conflict

If you conceive and build a room by first placing columns at the corners, and then gradually weaving the walls and ceiling round them, the room needs a perimeter beam around its upper edge.

Resolution

Build a continuous perimeter beam around the room, strong enough to resist the horizontal thrust of the vault above, to spread the loads from upper stories onto the columns, to tie the columns together, and to function as a lintel over openings in the wall. Make this beam continuous with columns, walls and floor above, and columns and walls below.

Closing context:
Floor-Ceiling Vaults, Column Connection