That action was upheld on appeal and was then reaffirmed last year by the ICC code development committee that oversees the IRC. Those requirements were extended to single family homes in 2006 via an optional IRC appendix, and in 2008, ICC members approved fire sprinklers as a standard feature to be included in all new homes. ICC’s legacy organizations began requiring fire sprinklers in multifamily occupancies in the 1980s. ICC’s membership has spoken very clearly on the issue of residential fire sprinklers, implementing requirements using a gradual and measured approach over a period of more than 20 years. Instead, proposals to rescind sprinkler requirements from the IRC were automatically disapproved, without discussion, as part of a consent agenda. Accordingly, under ICC regulations, requirements for residential sprinklers were not subject to debate at ICC’s final action hearing in Dallas in May. No public comments challenging code requirements for residential fire sprinklers were filed for consideration at the ICC Final Action Hearing in Dallas, TX. May 2010 International Residential Code 2012 Edition Retains Fire Sprinkler Requirement for New Homes Having continued in five editions of the IRC, it is clear that the nationally recognized standard of care for new home construction includes providing a home fire sprinkler system. Three complete additional code cycles have been completed since the 2012 IRC was published, and the IRC has continued to retain the fire sprinkler requirement for new homes despite numerous proposals seeking to have the requirement removed.
Good luck with this! My understanding is we are in a transition, and IRC will eventually adopt the same methods as IBC.Today International Residential Code 2015, 20 Editions Continue to Retain Fire Sprinkler Requirement for New Homes It was already unnecessary to go to Vult in my opinion, but then for IRC to not follow IBC is really strange. These code people are obviously not designers because this new code will lead to more confusion and more errors (and how would a building official understand this? they don't see combos used, only mph on drawings).
What a mess! I am planning on using Vult from ASCE 7 10 for both IBC and IRC for wind to avoid load combo confusion. So if you are using IRC wind speeds, you should use the old ASCE 7 05 load combinations - but that is no longer a reference standard! Therefore, one option is if you are using IRC wind speeds, you can factor them up by 1/0.775 to get pressures, and then use the ASCE-7 2010 combinations. Here is another problem - if I have a house and I choose to use the IRC/SBC-2 wind speeds (say 100mph based on Vasd), I better not use the ASCE-7 10 combinations - that is double dipping since there is already a 0.6W factor within the new ASD combos (instead of 1.0W). Yes, this is going to lead to much confusion because load cases are now mixed up with load combinations. So, for Providence 133mph x 0.775 = 103 approx= 100mph which is what can be used in IRC/SBC-2 (this conversion is also necessary when comparing to others standards/triggers that are not updated). Per IBC 2012 section 1609.3.1 you can get back to ASD values by multiplying the ult values by the square root of 0.6 (or 0.775). So it is Vult for IBC and Vasd for IRC - but both use ASCE-7 2010 as the reference standard. The IBC has gone to an ultimate strength value to be used (LRFD) while the IRC has the old 3-sec gust data (based on ASD). Not a big deal but here is the problem.īelieve it or not, our brilliant code writers are using different wind speeds now for the IRC and IBC codes. So for Boston wind pressure went down about 8% +/-, but in Providence it went up about 10% +/. For Boston, the wind in Cat II went from 105mph to 128mph, and 128mph^2/105mph^2 = 1.49 which is less than 1.6. It also depends a little on type of load combinations. Since wind pressure is proportional to velocity squared, it turns out that in Providence, wind pressure did increase a little overall, since wind speed increased 133mph^2/100mph^2 = 1.77, but the load factor in the ASCE 7 10 combos only went down from 1.6 to 1 (so wind pressure after doing the load combinations did still increase about 10% or 1.77/1.6 in Providence). That increase is counter balanced by new load combinations that reduce the wind load factor within the ASCE 7 USD/LRFD combos from 1.6 to 1.0 (or from 0.8 to 0.5) depending on the combination used. For example, in the typical risk cat II, wind speed in Providence is now 133 mph (instead of 100 mph before). One big change from IBC 2009 / ASCE 7 05 is that wind speeds in IBC 2012 / ASCE 7 10 are now "ultimate" values and associated with risk category and have increased about 30%.
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