International Residential Code Council Communities:
If your community has adopted the IRC, reference the 2009 edition of the International Residential Code®.
IRC 2009 Edition Code Text
SECTION R313 - AUTOMATIC FIRE SPRINKLER SYSTEMS
Townhouses
R313.1 Townhouse automatic fire sprinkler systems. An automatic residential fire sprinkler system shall be installed in townhouses.
Exception:An automatic residential fire sprinkler system shall not be required when additions or alterations are made to existing townhouses that do not have an automatic residential fire sprinkler system installed.
R313.1.1 Design and installation. Automatic residential fire sprinkler systems for townhouses shall be designed and installed in accordance with Section P2904.
One- and Two-Family Dwellings
R313.2 One- and two-family dwellings automatic fire systems.Effective January 1, 2011, an automatic residential fire sprinkler system shall be installed in one- and two- family dwellings.
Exception:An automatic residential fire sprinkler system shall not be required for additions or alterations to existing buildings that are not already provided with an automatic residential sprinkler system.
R313.2.1 Design and installation.Automatic residential fire sprinkler systems shall be designed and installed in accordance with Section P2904 or NFPA 13D.
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