Life Safety

Building A Storm Shelter to ICC-500 Requirements

The need for storm shel­ters is greater than ever as the 2017 tor­na­do sea­son kicks off to a pow­er­ful start. As of March 21, 2017, there have been 367 report­ed tor­na­does and, as of April 4, there have been 26 deaths due to tor­na­does in the Unit­ed States. That is more tor­na­does than the com­bined total dur­ing the months of Jan­u­ary, Feb­ru­ary and March in 2014, 2015, and 2016 of 313. It also makes Jan­u­ary 2017 the sec­ond-dead­liest month on record due to tor­na­does. The major­i­ty of peo­ple who have died in 2017, lived in mobile homes and hous­es; with­out the safe­ty of a storm shel­ter.

The ICC-500 Design and Construction of Storm Shelters

In 2003 the Inter­na­tion­al Code Coun­cil (ICC) and the Nation­al Storm Shel­ter Asso­ci­a­tion (NSSA) began work­ing togeth­er to devel­op a nation­al con­sen­sus stan­dard for storm shel­ters. It was named the ICC/NSSA Stan­dard for Design and Con­struc­tion of Storm Shel­ters (ICC-500). The FEMA P‑361 served as the frame­work for the devel­op­ment of the ICC-500 and the stan­dards for the ICC-500 are accred­it­ed by the Amer­i­can Nation­al Stan­dards Insti­tute (ANSI)The pur­pose of the ICC-500 was to pro­vide design stan­dards for a storm shel­ter that would ensure the safe­ty of those in a build­ing from storms that pro­duce high winds and fly­ing debris. The first pub­li­ca­tion of the ICC-500 occurred the sum­mer of 2008. Since 2009, the Inter­na­tion­al Build­ing Code (IBC, Sec­tion 423) and Inter­na­tion­al Res­i­den­tial Code (IRC, Sec­tion R323) have uti­lized ICC-500 as their ref­er­ence standard6 and require build­ing storm shel­ters accord­ing to ICC-500. The ICC-500 pro­vides builders, engi­neers, archi­tects, etc. a guide for occu­pan­cy safe­ty require­ments along with wind speed and debris impact resis­tance for storm shel­ters.

The 2014 Inter­na­tion­al Code Council’s (ICC) ICC-500 is the most cur­rent ICC/NSSA stan­dards for con­struc­tion and design and con­struc­tion of res­i­den­tial and com­mu­ni­ty storm shel­ters. There are sev­er­al basic cri­te­ria to the 2014 ICC-500.

  • The stan­dard is intend­ed for use by gov­ern­ment agen­cies and orga­ni­za­tions along with mod­el codes to achieve con­sis­ten­cy in the design and con­struc­tion of storm shel­ters
  • ICC-500 cov­ers the design, con­struc­tion, instal­la­tion, and inspec­tion of both com­mu­ni­ty and res­i­den­tial storm shel­ters
  • Res­i­den­tial storm shel­ters have a capac­i­ty not to exceed 16 peo­ple
  • Com­mu­ni­ty storm shel­ters are not res­i­den­tial storm shel­ters
  • Storm shel­ters can be sep­a­rate, detached build­ings, or enclosed or par­tial­ly enclosed with­in a host build­ing
  • The 2015 edi­tion of the IBC-Sec­tion 423 requires that if the fol­low­ing types of build­ings, locat­ed in a 250 mph wind speed zone, the build­ings must include a storm shel­ter as spec­i­fied and in accor­dance with the ICC-500Fig­ure 304.2(1).
  1. K‑12 school build­ings with a capac­i­ty of 50 or more occu­pants, with cer­tain excep­tion
  2. Emer­gency oper­a­tions cen­ters
  3. Fire, res­cue, and ambu­lance sta­tions
  4. Police sta­tions
  5. 911 call sta­tions

The ICC-500 Requirements for Building a Storm Shelter

The ICC-500’s design of a storm shel­ter far exceeds the wind load and per­for­mance require­ments of a reg­u­lar build­ing code. A shel­ter’s enve­lope must with­stand wind-borne debris, the col­lapse of the adja­cent struc­tures, falling objects, etc. A shel­ter must have a strong con­tin­u­ous load path that resists over­turn­ing, uplift, and foun­da­tion con­nec­tion fail­ure. Storm shel­ters in areas spec­i­fied by the ICC-500Fig­ure 304.2(1) must meet the require­ments of both the 2015 IBC and the ICC-500. These require­ments apply to shel­ters that are sep­a­rate, detached build­ings or con­struct­ed as safe rooms with­in a build­ing. Here is a list of the require­ments for a storm shel­ter as spec­i­fied by ICC-500:

  • Storm shel­ters must be large enough to accom­mo­date all the occu­pants of the build­ing
  • The loca­tion of the storm shel­ters must be with­in the build­ings they serve or locat­ed no more than 1000 feet from at least one exte­ri­or door of the build­ing
  • The 2015 IBC requires exit doors in the enve­lope of the storm shel­ter. The num­ber of exit doors is depen­dent on the num­ber of occu­pants. Each exit door must have an emer­gency escape
  • The storm shel­ters must pro­vide a min­i­mum lev­el of nat­ur­al or mechan­i­cal ven­ti­la­tion and light­ing
  • Toi­lets and hand wash sys­tems have to be inde­pen­dent of city sys­tems
  • The entire enve­lope of the storm shel­ter must meet the struc­tur­al cri­te­ria of ICC- 500. The design of the shel­ter must resist a 250 mph design wind speed, and resist the impact and cycli­cal pres­sure in accor­dance with ASTM E1886/ E1996. Also, the walls of the safe room must with­stand a debris mis­sile impact of a 15-pound 2‑inch X 4‑inch shot at 100 mph and the roofs must with­stand an impact of a 15-pound 2‑inch X 4‑inch shot at 67 mph

Bautex™ Block Wall Assembly Exceeds ICC-500 Requirements for Storm Shelter Design

Bau­tex Block Wall Assembly’s con­crete grid and con­tin­u­ous wall sys­tem meet the Fed­er­al Emer­gency Man­age­ment Agency FEMA 320 and FEMA 361 guide­lines in storm zones with pos­si­ble wind speeds up to 250 miles per hour. The Bau­tex Block sin­gle inte­grat­ed con­crete assem­bly also meets or exceeds the fol­low­ing ICC-500 and FEMA stan­dards for debris impact.

  • Series 1 FEMA 320361 Bau­tex Block Pan­el with Brick Veneer.
  • Series 2 FEMA 320361 Bau­tex Block Pan­el with CMU Block Veneer.
  • Test pro­jec­tile 15 lb. wood­en 2‑inch X 4‑inch pro­pelled at 100 mph.

Build­ings in regions with 250 mph wind speeds for tor­na­does must include a storm shel­ter in their design. Design and con­struc­tion of the storm shel­ters must meet the require­ments of both the 2015 IBC and the ICC-500. An ide­al choice for mate­r­i­al for build­ing a storm shel­ter is the Bau­tex Block Wall Assem­bly. It meets all require­ments for wind speed and impact resis­tance. In addi­tion the Bau­tex Block is insu­lat­ed, fire resis­tant and has above-grade mois­ture pro­tec­tion.

The Inter­na­tion­al Code Coun­cil (ICC) is a non-prof­it, mem­ber­ship asso­ci­a­tion ded­i­cat­ed to the devel­op­ment of a sin­gle set of com­pre­hen­sive and coor­di­nat­ed nation­al mod­ela con­struc­tion codes (I‑Codes). The Inter­na­tion­al Code Coun­cil (ICC) has three Fam­i­ly of Com­pa­nies.

  • The ICC Eval­u­a­tion Ser­vice (ICC-ES) eval­u­ates build­ing prod­ucts for com­pli­ance with I‑Codes
  • The Solar Rat­ing & Cer­ti­fi­ca­tion Cor­po­ra­tion (SRCC) pro­vides author­i­ta­tive per­for­mance rat­ings, cer­ti­fi­ca­tions, and stan­dards for renew­able ener­gy prod­ucts
  • The Inter­na­tion­al Accred­i­ta­tion Ser­vice (IAS) pro­vides objec­tive evi­dence that cal­i­bra­tion lab­o­ra­to­ries, inspec­tion agen­cies, build­ing depart­ments, fab­ri­ca­tor inspec­tion pro­grams and IBC spe­cial inspec­tion agen­cies.

Mod­el con­struc­tion codes are devel­oped and main­tained by a stan­dards orga­ni­za­tion (like the ICC) which is inde­pen­dent of the com­pa­ny or gov­ern­ment insti­tu­tion that is respon­si­ble for impos­ing the build­ing code on a con­struc­tion project.

Local and State gov­ern­ments use I‑Codes to design, build and com­pli­ance process to con­struct safe, sus­tain­able, afford­able and resilient struc­tures. Gov­ern­ment agen­cies depend on the ICC mod­el I‑Codes because of the com­plex­i­ty and cost of devel­op­ing build­ing codes and stan­dards. Cur­rent­ly, fifty states and the Dis­trict of Colum­bia have adopt­ed the ICC mod­el I‑Codes; alter­ing them to fit spe­cif­ic local con­struc­tion prac­tices, cli­mate, and geog­ra­phy.

The Nation­al Storm Shel­ter Asso­ci­a­tion (NSSA began in 2000, in Lub­bock, Texas. The Nation­al Storm Shel­ter Asso­ci­a­tion ini­tial pur­pose was to rec­og­nize and give dis­tinc­tion to storm shel­ter pro­duc­ers and prod­ucts who meet high stan­dards of qual­i­ty. The first major task of the NSSA was to deter­mine these high indus­try stan­dards for storm shel­ters. The Nation­al Storm Shel­ter Asso­ci­a­tion (NSSA) worked alone to devel­op codes until 2002. In 2002 an agree­ment was reached between NSSA and ICC to devel­op a nation­al con­sen­sus stan­dard for storm shel­ters. Accred­i­ta­tion of the stan­dards is by the Amer­i­can Nation­al Stan­dards Insti­tute (ANSI). The ICC/NSSA Stan­dard for Design and Con­struc­tion of Storm Shel­ters is named the Inter­na­tion­al Code Coun­cil-500 (ICC-500).

FEMA P‑361 — Safe Rooms for Tor­na­does and Hur­ri­canes — was first pub­lished in 2000 and is intend­ed for archi­tects, engi­neers, build­ing offi­cials, local offi­cials and emer­gency man­agers, and prospec­tive safe room own­ers and oper­a­tors. It guides the plan­ning, design, con­struc­tion, and oper­a­tion of res­i­den­tial and com­mu­ni­ty safe rooms that will pro­tect peo­ple dur­ing extreme wind events. The FEMA P‑361 is intend­ed for those seek­ing more tech­ni­cal guid­ance than FEMA P‑320 pro­vides.

The 2015 Inter­na­tion­al Build­ing Code (IBC) is admin­is­tered by the ICC and con­tains com­mer­cial con­struc­tion reg­u­la­tions. The Inter­na­tion­al Res­i­den­tial Code (IRC) is admin­is­tered by the ICC and con­tains res­i­den­tial con­struc­tion and remod­el­ing reg­u­la­tions. The IRC is used or adopt­ed in 49 states, Guam, the Dis­trict of Colum­bia, Puer­to Rico and the U.S. Vir­gin Islands. The IBC is used or adopt­ed in 50 states, the Dis­trict of Colum­bia, Guam, North­ern Mar­i­anas Islands, New York City, Puer­to Rico and the U.S. Vir­gin Islands. The IBC and IRC are mod­el build­ing codes that com­mu­ni­ties can adopt in whole or adapt to fit the local con­struc­tion prac­tices, cli­mate, and geog­ra­phy. Only If the IBC or IRC are adopt­ed whole, they become legal in a com­mu­ni­ty. The IRC and IBC are designed to pro­vide build­ing safe­guards to pub­lic health, safe­ty, and wel­fare. The codes intend to pro­tect pub­lic health and safe­ty while avoid­ing both unnec­es­sary costs and pref­er­en­tial treat­ment of par­tic­u­lar mate­ri­als or meth­ods of con­struc­tion. The 2015 IBC and IRC are ful­ly com­pat­i­ble with all oth­er pub­lished ICC codes.

The ICC ref­er­enced stan­dard is an indus­try agree­ment of the lev­el of per­for­mance in the design­ing man­u­fac­tur­ing, test­ing and installing of mate­ri­als, prod­ucts or assem­blies. A ref­er­enced stan­dard is a ref­er­enced reli­able resource. It is not a pri­ma­ry law; like a mod­el code. A mod­el code becomes law when adopt­ed by a juris­dic­tion. A stan­dard becomes law when ref­er­enced in a mod­el code. Ref­er­enced stan­dards are an exten­sion of the code require­ments and are there­fore equal­ly enforce­able.

2015 IBC — Sec­tion 423.4 — Storm Shel­ters. Schools with 50 or more peo­ple and where shel­ter design wind speeds are 250 mph, as spec­i­fied by Fig­ure 304.2(1) of ICC 500 must have a storm shel­ter (safe room). The shel­ter must be large enough for every­one in the school.

FEMA P‑320 — Tak­ing Shel­ter from the Storm — was first pub­lished in 1998 and is meant for builders, con­trac­tors, and home­own­ers for deci­sion-mak­ing guid­ance on tor­na­do and hur­ri­cane safe rooms. The FEMA P‑320 also has spe­cif­ic require­ments for a safe room, which use ICC 500 as a ref­er­enced stan­dard, how­ev­er, are con­sid­ered slight­ly more con­ser­v­a­tive.

  • Safe rooms must be anchored to the build­ing’s foun­da­tion to resist over­turn­ing and uplift
  • A safe room must have a con­tin­u­ous load path that resists lat­er­al and uplift loads dur­ing high winds.
  • The roof, open­ings, and walls of a safe room must resist per­fo­ra­tion by wind­borne debris.
  • The walls of the safe room are inde­pen­dent of the rest of the build­ing.