North Carolina

Primary Contact for State Adoption

Rob Roegner
Senior Deputy Commissioner of Engineering

North Carolina Department of Insurance

United States

Secondary Contact for State Adoption

Carl Martin
Deputy Commissioner of Engineering

North Carolina Department of Insurance

NC 27699-1202
United States
Dan Dittman
Chief Energy Code Consultant

North Carolina Department of Insurance

United States

Regional Energy Efficiency Organization

Maggie Kelley Riggins

Southeast Energy Efficiency Alliance (SEEA)

United States

State Profile

Code Type: Commercial Residential
Current State Code 2015 IECC and ASHRAE 90.1-2013 with amendments 2015 IECC with amendments
Effective Date
Adoption Date
State Amendment Yes No
Can use COM/REScheck Yes Yes


Commercial Residential
Current Model Code ASHRAE Standard 90.1-2007 2009 IECC
Yes Yes

State Code Analysis

Code Type: Residential Commercial
Energy Efficiency
State Amendment Yes Yes
Amendment Summary

2018 North Carolina Energy Conservation Code (based on 2015 IECC with amendments). Mandatory compliance began Jan. 1, 2019.

Amendments include:

  • R403.3 – Duct Leakage Testing  (new exception) – duct systems smaller than 750 ft2 do not have to be tested.  This exception excludes small duct systems and thus represents a weakening of the code. 
  • R406.2 – ERI Mandatory requirements (modification) – change mandatory duct insulation from R-6 to R-8 or R-4 or R-0, depending on location of ducts.      
  • R402.1.1 – Vapor retarder – deleted. 
  • Table R402.1.2 – R-values – Mixed bag – some up some down, although mostly down.  . 
  • Table R402.1.4 – U-factors – same mixed bag, but mostly decrease in stringency.   
  • R402.2.  Air leakage testing – weakens requirements for NC from 3 to 5 ACH50. 
  • R403.3 – Duct Insulation – modifies duct requirements with some up and some down. 
  • R403.3 – Duct Tightness – weakens duct leakage from 5 to 4 for total leakage.
  • R403.5 – Service Water Heating Systems – removes all except circulating system pipe insulation
  • R403.6 – Mechanical Ventilation – removes fan efficiency requirements
  • R403.9 – Snow and Ice Melt Equipment – Modified to eliminate control requirements for no precipitation falling and outdoor temp above 40F.   
  • R403.11 - spas - deleted..

2018 North Carolina Building Code (based on the 2015 IECC with amendments):

  • 101.2 Scope of NC Energy Code – “Per G.S. 143-138 (b18), no energy conservation code provisions shall apply to any structure for which the primary occupancy classification is Group F, S, or U. This exclusion shall apply to the entire building area.” Group F is “Factory and Industrial” and appears to include only facilities that are actually involved in manufacturing.  Group S is “Storage” and appears to include any storage facilities that are not hazardous storage. 
  • Table C402.1.3 – R-value requirements – removes all zones but 3, 4, and 5.  Weakens metal building roof requirements in CZ3.  Adds new LS option for metal building roofs in CZ4 and CZ5 (while keeping original requirement).  Increases wood frame wall requirements for CZ 4 and CZ5 to R42.  Add new row of requirements for steel framed roofs.  Increases mass wall R-value in CZ5.  Revises metal building walls to generally less stringent (although All Other in CZ3 is slightly more stringent).  
  • Table C402.1.4 – U-factor requirements – changes corresponding to changes in Table C402.1.3. 
  • C402.2.5 – slab insulation protection requirements eliminated. 
  • Table C402.4 – fenestration requirements – simplified to only CZ3, 4, and 5. 
  • Various sections – greater WWR or SRR with daylighting and minimum WWR and SRR – dropped.  
  • C402.5.3 – Rooms with fuel burning appliances – dropped
  • C402.5.4 – Doors and access opening to shafts – dropped
  • C402.5.7 – Statement that revolving doors don’t replace vestibules – dropped
  • C403.1 – Walk-in cooler and freezer requirements – dropped.  All corresponding refrigeration requirements in other parts of C403 also deleted. 
  • Table C403.2.3(10) – Heat Exchangers – Dropped. 
  • C403.2.4.4 – Zone Isolation – Dropped. 
  • C403.2.4.5 – Snow and Ice Melt Equipment – Modified to eliminate control requirements for no precipitation falling and outdoor temp above 40F. 
  • C403.2.4.7 – Economizer diagnostics – deleted. 
  • C403.2.6.1 – Demand control ventilation – modified. 
  • C403.2.6.2 – Enclosed parking garage ventilation controls – deleted. 
  • C403.2.7 – Energy Recovery – modified.  Last 2 pages of section deleted, but main requirement maintained. 
  • C403.2.8 – Kitchen Exhaust Systems – Deleted.  
  • C403.2.9 – Duct leakage – equations modified. 
  • C403.2.10 – Piping insulation – exceptions and piping insulation protection deleted. 
  • C403.2.12.3 – Fan efficiency – deleted. 
  • C403.3 – Economizers – simplified.  
  • Table C403.2 – Economizer tradeoff – Percentage improvement greatly raised. 
  • C403.3.3.3 – High Limit shutoff of air economizers.  All reference to high limit shutoff removed.  
  • C403.4.1.2 – static pressure set point location – deleted. 
  • C403.4.1.3 – set points for digital controls – instructions on how to reset deleted. 
  • C403.4.2.4 – Part load controls – lowers threshold for hydronic heating systems to have part load controls. 
  • C403.4.3 – heat rejection equipment – removed all but opening paragraph.  
  • C403.4.4.4 – fractional HP fan motors – deleted. 
  • C403.4.4.6 – multizone VAV optimization – deleted.
  • C404.2.1 – High-input rated service water heating systems – deleted.  
  • C404.5 – Efficient water heating piping – deleted.   
  • C404.7 – demand recirculation controls – deleted. 
  • C404.8 – drain water heat recovery – deleted.   
  • C404.10 – spas – deleted.  
  • C405.2.1 – occupancy sensors – added computer rooms, but deleted “other rooms”.    
  • C405.2.3 – daylighting controls – deleted. 
  • C406.5 – DOAS Additional efficiency package – modified. 

Model Code Savings Potential

Statewide Savings Potential (2010-2030) Residential Commercial
Cost $1.65B $0.78B
Energy (primary) 155MBtu 104MBtu
Consumer Cost Savings Residential
per Home
per 1,000 ft2
Annual ($) $157 $106
Annual (%) 11.0%
Life-cycle (30 year) $2052 $2310
Simple Payback 5.3 years 0.0 years
Positive Cash Flow 0.6 years


Code Type: Residential Commercial
Field Study Yes No
Training Program No No


Additional Information

    In December 1973 the North Carolina State Building Code Council adopted the Southern Building Code Congress (SBCC) Standard Building Code insulating standards as statewide requirements. These standards were found to be too "prescriptive" and did not meet the particular requirements of North Carolina; therefore, an energy subcommittee was appointed to investigate energy conservation and study the ASHRAE standards that were being developed. The committee recommended new energy requirements in March 1977, and the Building Code Council adopted these standards, which went into effect on January 1, 1978.

    In June 1991 an ad hoc energy committee was appointed by the Building Code Council to study and update the energy requirements in the state building code. This committee began studying the state's current code as well as the 1989 MEC. The Energy Policy Act of 1992 shifted and refocused the committee's study efforts. The committee completed its review of the 1992 MEC and the Building Code Council adopted the proposed new standards for one- and two-family dwellings, which became effective on April 15, 1993.

    The 1994 SBCC Standard Building Code with North Carolina amendments was adopted by the Building Code Council and is known as the 1996 North Carolina Edition of the North Carolina State Building Code. The energy requirements are contained in the new edition as Chapter 13. Chapter 13 provides very simple prescriptive requirements for thermal envelope and references the new Volume X (Energy) for other systems.

    In March 1995 the Building Code Council adopted Volume X (Energy) as the new energy code for North Carolina. These new energy requirements became effective July 1, 1996. Volume X is a reprint of ASHRAE/IESNA 90.1-1989 (codified version) with North Carolina amendments. The code applies to commercial buildings, including those used for assembly, business, education, and storage, as well as institutions and merchants. High-rise and multi-family residential buildings are also covered under Volume X.

    On June 11, 1996, the Building Code Council adopted the 1995 CABO One- and Two-Family Dwelling Code with North Carolina amendments effective July 1, 1997. Chapter 39 contains a simplified prescriptive requirements for meeting the 1995 MEC based on REScheck.

    The previous state code was based on the 2000 IECC, and was effective December 31, 2001.

    Effective July 1, 2006, the base document for the 2006 North Carolina Energy Conservation Code is the 2003 IECC. The 2006 NC Amendments are replacements to the Sections printed in the base document. The 2004 Supplement to the I-Codes is referenced in various Sections of the 2006 NC Amendments.

    On March 11, 2008, the 2009 North Carolina Energy Conservation Code was adopted. Based on the 2006 IECC (and referencing ASHRAE 90.1-2004 for commercial buildings), the code includes strengthening amendments to the base code, requiring fenestration U-factor and SHGC values of 0.40 across the state. Builders are allowed to use the previous code until June 30, 2009.

    The NC Building Code Council expects to begin the next code update process in the spring of 2009 with an anticipated effective date of January 1, 2012. While the 2009 IECC will be used as the base code, the state was awarded a $500,000 federal grant to improve its next code's energy efficiency by 30% and improve compliance through comprehensive training and enforcement.

    On Friday, June 24, 2011, Governor Beverly Perdue signed SB 708 into law and approved a new Energy Conservation Code for the residential and commercial buildings in North Carolina. This new code will save home and business owners money on their monthly energy bills and help retain and create jobs in every region of the state. It delivers significant improvements in insulation levels, window performance and building envelope air leakage reduction. The new code also includes the High Efficiency Residential Option (HERO) Appendix which delivers a 30% improvement in minimum energy efficiency over the state's current energy code. The new NC Energy Conservation Code became effective January 1, 2012 with mandatory compliance beginning March 1, 2012.

    State-owned buildings must be designed, constructed, and certified to exceed the energy efficiency requirements of ASHRAE 90.1-2004 by 30% for new buildings, and 20% for major renovations. The energy consumption per gross square foot for all State buildings in total must be reduced by 20% by 2010, and 30% by 2015, based on consumption during the 2003-2004 fiscal year. Senate Bill 668 of 2007 and Senate Bill 1946 of 2008 established several policies which will reduce the amount of energy, water, and other resources consumed by the State government in their buildings and facilities. These standards apply to all new buildings owned by the State, the University of North Carolina, and the North Carolina Community College system, which are larger than 20,000 gross square feet.

    Also included are renovation projects when the cost is greater than 50% of the insurance value and the project is greater than 20,000 square feet. These projects must be designed, constructed and certified to exceed the energy efficiency requirements of ASHRAE 90.1-2004 by 30% for new buildings, and 20% for major renovations. Additionally, new buildings must consume 20% less potable water than the North Carolina Plumbing Code requires, and 50% less outdoor water than typical facilities using conventional systems.

    Existing buildings purchased by the State must also meet certain energy and water conservation standards. Buildings purchased by the State must meet whatever State law or local ordinance was in effect during the time of its construction. Buildings having historic, architectural, or cultural significance, however, do not have to meet this standard.

    This bill goes further than similar standards adopted by other states by also making conservation requirements for existing state-owned buildings. No later than December 31, 2009, all existing state-owned buildings must make specific lighting upgrades, including the replacement of standard exit signs with ones that utilize LEDs and the replacement of incandescent light bulbs with compact fluorescent bulbs. Existing buildings must also install faucet aerators and low-flow shower heads, and adopt other methods to reduce either outdoor or indoor water consumption by 20% relative to a 2002-2003 baseline. When replacing HVAC equipment in an existing building, the specifications of the new system must be reviewed to ensure it is properly sized. Replacement motorized equipment must meet minimum performance standards established by the National Electric Manufacturers Association. And, when purchasing new office equipment and appliances, the new equipment must be Energy Star certified.

    The bill also refined a previous requirement for State buildings to reduce, in total, their energy consumption per square foot by 20% by 2010 and 30% by 2015, relative to energy consumption levels during the 2003-2004 fiscal year. To help meet this goal, The Department of Administration through the State Energy Office will develop a comprehensive program to help State agencies and State institutions of higher learning manage their consumption. This will include a requirement for the use of life-cycle cost analysis during the design phase to consider site orientation, the amount and type of fenestration and the potential for daylighting, the amount of insulation used, variable occupancy and operating conditions, and architectural features that affect the consumption of water, energy, and other utilities.

    The North Carolina State Building Code Council is responsible for developing all state codes. By statute, the Commissioner of Insurance has general supervision over the administration and enforcement of the North Carolina state building code. Engineering Division staff assist the Building Code Council. Rule proposals are considered quarterly and anyone may propose a rule change. Final authority to adopt criteria rests with the state legislature. Public hearings are conducted quarterly to consider proposals and must proceed through the rule making process.

    Local units of government enforce the code through the permit/inspection process for new construction and additions. The North Carolina Department of Insurance is responsible for general supervision of the effort statewide. Depending on the size of the local government unit, the same individual may be responsible for performing plan reviews and inspections.

    Compliance is determined by plan review and inspections through the normal building permit process. Compliance forms are included in the energy provisions for both residential and commercial buildings.