Commercial Buildings [ASCE 24-14, Sec. 6 and C6]
Dry Floodproofing is surrounding a building with barriers and sealants to higher than expected minimum flood levels to keep water from entering a building.
Dry floodproofing consists of sealed walls and foundations, anti-buoyancy measures with specially constructed watertight metal panels for doors and windows. Such measures need to extend at least one foot above the minimum flood level (the Base Flood Elevation or BFE) for a particular location.
Wet Floodproofing is a building designed to allow flood waters to freely enter and leave a building without causing damage.
Floodproof Versus Elevation
Only buildings used for non-residential purposes may be floodproofed in lieu of elevation, such as stores, offices, restaurants and etc. Such measures are usually applied to solid construction buildings, as wood-framed buildings are nearly impossible to floodproof to any acceptable degree. Floodproofing isn’t permitted for commercial buildings used for residential purposes, such as:
- Areas of hospitals/medical facilities where patients are housed
- Child/elder day care
- Motels and hotels
- Sleeping rooms for rent/lease
AE-Type Zones Only
Floodproofing isn’t permitted for buildings in or straddling "VE" type flood zones nor within Coastal A Zones.
Florida Building Code
The floodproofing requirements/standards won’t be found within the current Florida Building Code. This code incorporates a third-party standard, the American Society of Civil Engineer’s (ASCE) publication Number 24-14, "Flood Resistant Design and Construction." The relevant floodproofing chapters are sections 6 and 6C. Due to copyright protections, the City isn’t permitted to publish this booklet online.
Floodproofing Approval Phase Requirements (overview)
Phase I - Plan Review/Permitting Phase
- Any soil or fill adjacent to the structure compacted and protected against erosion and scour
- Building Plans w/general floodproofing overview, showing:
- Relevant flood zones identified
- Flood zones plotted on site plans
- BFE, Design Flood Elevation (DFE) and grade elevations shown
- Height of floodproofing relative to DFE
- Elevation Certificate (original, not copy)
- Emergency ingress/egress above floodproofing during flood conditions
- Floodproofing Certificate (construction drawings phase; original)
- Floodproofing Panels
- Sewerage backflow prevention measures
- Show materials below DFE - not protected by floodproofing - are resistant to salt water flood damage
- Show that walls are substantially impermeable to the passage of water.
- With load calculations
- Show that walls, floors, and flood shields shall be designed and constructed to resist hydrostatic, hydrodynamic, and other flood-related loads to relevant elevation.
- Including the effects of buoyancy resulting from flooding to the elevation.
- Statement plans in accordance with ASCE7 and 24-14
- Satisfies "combination of loads" requirement
Phase II - Final Inspection/Certificate of Occupancy Phase
- Emergency Operation Plan
- Floodproofing Certificate (finished construction phase)
- Inspection and Maintenance Plan
- Local agency review/inspection
- Shop drawings for each flood panel type w/load calculations
- Certified by a State of Florida licensed Engineer