SUBCODE "A" (THE PHILADELPHIA ADMINISTRATIVE CODE)
SECTION B-1805 [17.1] FOOTINGS AND FOUNDATIONS
B-1805.2.1 Frost protection. Except where otherwise
protected from frost, foundation walls, piers and other permanent supports of
buildings and structures shall be protected from frost by one or more of the
following methods:
1. Extending below the frost line of
[the locality] 30 inches (762 mm);
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