Use the filters below to find answers to frequently asked questions about Building Science guidance regarding:
If you need additional information, please email the FEMA Building Science Helpline or call at 866-927-2104.
Please visit the Building Science Resource Library to reference all hazard-specific publications and guidance documents.
There are several possible locations in or near your home for a safe room. It can be either inside (within the building footprint) or outside (detached or adjacent to the existing ) and above-ground, in-ground, or in a basement. Many people prefer to build within their homes so they have some level of protection while attempting to access their safe room. For an existing home, this convenience must be balanced with the challenges of retrofitting the building. When determining where to locate a safe room, the owner must determine what is best for situation. For example, while an interior safe room offers the benefit of providing quicker accessibility, an exterior safe room may be easier to install for an existing building.
For more information on selecting the location of a safe room within your home or small business, see FEMA P-320, Section 3.5.
FEMA P-320 has prescriptive safe room plans for safe rooms sized between 8 feet x 8 feet x 8 feet tall and 14 feet x 14 feet x 8 feet tall. However, a safe room can be customized to meet your individual needs. Therefore, a safe room can be sized differently as long as it complies with current FEMA P-361 criteria. When changing any details of the prescriptive plans in FEMA P-320, consult a licensed design professional to verify that the modified plans still meet or exceed the design criteria of FEMA P-361. The design professional should be licensed in the state in which the safe room will be constructed or installed. If you are unsure if a safe room or storm shelter product meets FEMA P-361 criteria, you may contact your local building official or local or state emergency management office.
An emergency supply kit should be kept within the safe room. Section 6.2 in FEMA P-320 provides guidance on the emergency supply kit including a checklist of suggested items. The kit can include tools to open damaged doors such as a crowbar, jack or spreader.
An important part of any emergency plan for a safe room should include notifying local emergency managers, first responders (local fire stations), and family members or others of the safe room location. This should be done by registering the precise coordinates (latitude and longitude) of the safe room’s entrance with your local officials. (Note that this should be done as soon as the safe room is constructed – not as an extreme wind event approaches). This will allow emergency personnel to find and quickly free you after a storm if your safe room’s exit becomes blocked by debris.
No. FEMA does not approve, endorse, certify, or recommend any contractors, individuals, firms, or products. While a product may be in compliance with FEMA design guidance, contractors, individuals, or firms, shall not state they are, or produce products that are "FEMA approved" or "FEMA certified."
FEMA’s Technical Bulletin (TB) 2, Flood Damage-Resistant Materials Requirements for Buildings Located in Special Flood Hazard Areas (FEMA, 2008, revised 2010), provides guidance on the National Flood Insurance Program (NFIP) regulations concerning the required use of flood-damage resistant construction materials for building components located below the base flood elevation (BFE) in Special Flood Hazard Areas in both Zone A and Zone V. TB 2 provides a classification scheme for flood damage-resistant materials, as well as a table of common building materials, and describes whether they are allowed for use in construction below the BFE. Check with the local jurisdiction for additional requirements for use of materials below elevated buildings.
References: FEMA. 2008, revised 2010. Flood Damage-Resistant Materials Requirements for Buildings Located in Special Flood Hazard Areas in Accordance with the National Flood Insurance Program. NFIP Technical Bulletin 2. Washington, DC, August 2008.
he National Flood Insurance Program (NFIP) requires that the heating, ventilation, and air conditioning (HVAC) system in new construction or Substantial Improvement in a Special Flood Hazard Area (SFHA) be elevated above the base flood elevation (BFE) or designed so that floodwaters cannot infiltrate or accumulate within any component of the system.
All structural and nonstructural building components at or below the BFE must be constructed of materials resistant to flood damage. Flood damage-resistant materials must be used for all building elements subject to exposure to floodwaters, including floor joists, insulation, and ductwork. Building components that do not use flood damage-resistant materials must be elevated above the BFE. A flood damage-resistant material is defined as any building material capable of withstanding direct and prolonged contact with floodwaters without sustaining significant damage. Prolonged contact is defined as contact with floodwaters for a minimum of 72 hours and significant damage refers to any damage requiring more than low-cost cosmetic repair (such as painting). The cost of repair should be less than the cost of replacement for the material or system. This requirement applies regardless of the expected or historical flood duration.
The NFIP does not recommend installing ductwork below the BFE in new construction or Substantial Improvement located in an SFHA. There is no known cost-effective technique for designing air ducts to keep floodwaters from entering or accumulating within the system components during a flood. If ductwork must be installed below the BFE, it should be minimized as much as possible. The ducts must be composed of impermeable and watertight material, such as welded seamless ductwork or large-diameter PVC pipe. Such material is expensive, but practical when a short length of ductwork descends below the BFE.
In a Coastal High Hazard Area, structures in the Coastal A Zone (areas in Zone A that are subject to wave heights more than 1.5 feet) and Zone V can be significantly damaged by wave action. In Zone V, the lowest horizontal structural member must be installed at or above the BFE. Anything below the BFE is regarded as an obstruction and can result in increased flood insurance premiums. Ductwork below the BFE should be avoided at all costs in Zone V and Coastal A Zones because it is difficult to design and construct a ductwork system that will sustain not only the hydrostatic loading, but also the additional hydrodynamic, wave forces and debris impact loads in these flood zones.
For more information on this topic, see:
In addition to the SDE tool, the following FEMA tools are available:
Chapter 2 of FEMA P-320 provides information to help homeowners determine whether their home needs a safe room. Building owners should ask themselves several questions when considering whether to install a safe room:
Chapter A2 of FEMA P-361 includes guidance to help communities and building owners determine the level of risk posed by these extreme wind events and can help people decide whether to install a safe room.
For a hurricane community safe room, the number of spaces for standing or seated, wheelchair-bound, or bedridden people should be determined based on the expected occupancy of the safe room as calculated by the designer and the applicable authority having jurisdiction. As a minimum, each community safe room should be sized to accommodate at least one wheelchair space for every 200 occupants.
It is also important to note that community safe rooms should provide equal access for all persons in accordance with all federal, state, and local Americans with Disabilities Act (ADA) requirements and ordinances. Table 2 shows the minimum safe room floor area per occupant for hurricane community safe rooms. The minimum usable floor area per safe room occupant is larger for a hurricane community safe room than for a tornado community safe room because occupants require a longer sheltering time for hurricanes.
| Hurricane Community Safe Room Occupant | Minimum Usable Floor Area* per Safe Room Occupant |
|---|---|
| Standing or Seated | 20 square feet |
| Using a Wheelchair | 20 square feet |
| Relocated to a Bed or a Stretcher | 40 square feet |
*See FEMA P-361 for more information on usable safe room floor area.
Yes. FEMA provides guidance on the location of residential safe rooms in relation to flood hazards.
Per FEMA P-361, flood hazards should be considered when designing a residential safe room. Flood loads acting on a structure containing a safe room are strongly influenced by the structure’s location relative to the flood source. Tornado or hurricane residential safe rooms should be located outside of the following high-risk flood hazard areas:
More information on these siting restrictions and additional elevation requirements can be found in the Flood Hazard Siting and Elevation Criteria for Residential Safe Rooms (fact sheet) and FEMA P-361.
