Bolted Down Tight

Corners experience the highest forces during wind events. Wind pressure creates both suction on downwind walls and direct pressure on windward walls. Where these walls meet at corners, the forces concentrate. Adding anchor bolts within 12 inches of each corner ensures these high-stress areas are properly secured to the foundation.

Florida Building Code requires a minimum 7-inch embedment into concrete for anchor bolts. This ensures the bolt has enough grip to resist both uplift and lateral forces without pulling out of the concrete. The bolt head or nut must be below the sill plate surface so the plate sits flat on the foundation.

Concrete screws can be used in some situations, but they have lower capacity than cast-in-place anchor bolts. For new construction in Palm Beach County, cast-in-place J-bolts or L-bolts are preferred because they cure with the concrete and provide maximum holding power. Concrete screws are better suited for retrofits where cast-in bolts are not possible.

Standard code allows up to 6 feet between anchor bolts for standard residential construction. However, in high wind areas like Palm Beach County, engineering calculations often require closer spacing - typically 4 feet or less. Corners always need bolts within 12 inches regardless of the standard spacing. Always follow your engineered plans, not just minimum code.

Yes, anchor bolts should have washers between the nut and the sill plate. The washer distributes the clamping force over a larger area of wood, preventing the nut from crushing into the wood over time. Use appropriately sized washers - typically 2-inch square plate washers for 1/2-inch bolts. In coastal areas, use stainless steel or galvanized washers to prevent corrosion.