Item 4D Ord 12471
2021 International Energy Conservation Code
ORDINANCE NO. 1247
AN ORDINANCE ADOPTING THE INTERNATIONAL ENERGY CONSERVATION
CODE, 2021 EDITION, REGULATING THE DESIGN OF BUILDING ENVELOPES
FOR ADEQUATE THERMAL RESISTANCE AND LOW AIR LEAKAGE AND THE
DESIGN AND SELECTION OF MECHANICAL, ELECTRICAL, SERVICE WATER-
HEATING AND ILLUMINATION SYSTEMS AND EQUIPMENT IN THE CITY OF
SOUTHLAKE; PROVIDING FOR THE ADOPTION OF LOCAL AMENDMENTS
THERETO; PROVIDING FOR RECORDING OF SUCH CODE AS A PUBLIC
RECORD; PROVIDING THAT THIS ORDINANCE SHALL BE CUMULATIVE OF ALL
ORDINANCES; PROVIDING A SEVERABILITY CLAUSE; PROVIDING FOR A
PENALTY FOR VIOLATIONS HEREOF; PROVIDING A SAVINGS CLAUSE;
PROVIDING FOR PUBLICATION IN PAMPHLET FORM; PROVIDING FOR
PUBLICATION IN THE OFFICIAL NEWSPAPER; AND PROVIDING AN EFFECTIVE
DATE.
WHEREAS, the City of Southlake is a home rule city acting under its charter
adopted by the electorate pursuant to Article XI, Section 5 of the Texas Constitution and
Chapter 9 of the Local Government Code; and
WHEREAS, the City Council of the City of Southlake deems it necessary to
adopt this ordinance governing the design of building envelopes for adequate thermal
resistance and low air leakage and the design of mechanical electrical, service water-
heating and illumination systems and equipment, in order to protect the health, safety
and welfare of the citizens of the City of Southlake.
WHEREAS, beginning in the spring of 2021, NCTCOG’s Regional Codes
Coordinating Committee (RCCC) and its five advisory boards conducted open review
meetings over a one-year period to review the 2021 editions of the International Codes
and to develop regional amendments. Their review and recommendations were
completed and endorsed by NCTCOG’s Executive Board in October, 2021. Now
NCTCOG encourages jurisdictions in North Central Texas to adopt the 2021
International Energy Conservation Code along with its respective regional amendments.
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NOW, THEREFORE, BE IT ORDAINED BY THE CITY COUNCIL OF THE CITY OF
SOUTHLAKE, TEXAS:
Section 1
Adoption
That the International Energy Conservation Code, 2021 Edition, published by the
International Code Council, including the standards referenced therein, is hereby
adopted as the Energy Conservation Code of the City of Southlake regulating the
design of building envelopes for adequate thermal resistance and low air leakage and
the design and selection of mechanical, electrical, service water-heating and
illumination systems and equipment in the City of Southlake. A True and correct copy of
this document is referenced in Exhibit "A."
Section 2
Amendments
That the 2021 International Energy Conservation Code, as adopted herein, is
hereby amended as provided in Exhibit "B" incorporated herein and attached hereto for
all purposes of this ordinance. The City of Southlake, Texas may from time to time
determine that additional local modifications to the Energy Conservation Code are
necessary and appropriate to meet the unique needs of the City of Southlake, Texas.
To effectuate these local modifications, the City Council shall enact individual
ordinances amending this Ordinance, fully setting forth the change to be made in the
Energy Conservation Code. These amendments shall be consolidated as Exhibit "B" to
this Ordinance.
Section 3
Recording
The material contained in Exhibits “A” and “B” to this ordinance shall not be
included in the formal municipal codification of ordinances but shall be maintained as a
public record in the office of the City Secretary and/or the office of Building Inspections
and will be available for public inspection and copying during regular business hours.
Section 4
Cumulative Clause
This ordinance shall be cumulative of all provisions of ordinances of the City of
Southlake, Texas, except where the provisions of this ordinance are in direct conflict
with the provisions of such ordinances, in which event the conflicting provisions of such
ordinances are hereby repealed.
Section 5
Severability
It is hereby declared to be the intention of the City council that the phrases,
clauses, sentences, paragraphs, and sections of this ordinance are severable, and if
any phrase, clause sentence, paragraph or section of this ordinance shall be declared
unconstitutional by the valid judgment or decree of any court of competent jurisdiction,
such unconstitutionality shall not affect any of the remaining phrases, clauses,
sentences, paragraphs and sections of this ordinance, since the same would have been
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enacted by the City Council without the incorporation in this ordinance of any such
unconstitutional phrase, clause, sentence, paragraph or section.
Section 6
Penalty
Any person, firm or corporation who violates, disobeys, omits. neglects or refuses
to comply with or who resists the enforcement of any of the provisions of this ordinance
shall be fined not more than Two Thousand Dollars ($ 2,000.00) for all violations
involving zoning, fire safety or public health and sanitation, including dumping or refuse,
and shall be fined not more than five hundred dollars ($500) for all other violations of
this ordinance each day that a violation is permitted to exist shall constitute a separate
offense.
Section 7
Saving Clause
All rights and remedies of the City of Southlake are expressly saved as to any
and all violations of the provisions of any ordinances affecting the regulation of the
design of building envelopes for adequate thermal resistance and low air leakage and
the design and selection of mechanical, electrical service water-heating and illumination
systems and equipment within the City which have accrued at the time of the effective
date of this ordinance; and, as to such accrued violations and all pending litigation, both
civil and criminal, whether pending in court or not, under such ordinances, same shall
not be affected by this ordinance but may be prosecuted until final disposition by the
courts.
Section 8
Publication
The City Secretary of the City of Southlake is hereby authorized to publish this
ordinance in book or pamphlet form for general distribution among the public, and the
operative provisions of this ordinance as so published shall be admissible in evidence in
all courts without further proof than the production thereof.
The City Secretary of the City of Southlake is hereby directed to publish in the
official newspaper of the City of Southlake, the caption, penalty clause, publication
clause and effective date of this ordinance one time within ten days after passage of this
ordinance, as required by Section 3.13 of the Charter of the City of Southlake.
Section 10
Effective Date
This ordinance shall be in full force and effect from and after its passage and publication
as required by law but not before May 1, 2022.
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APPROVED ON FIRST READING THIS 5 DAY OF APRIL, 2022.
MAYOR
ATTEST:
CITY SECRETARY
APPROVED ON SECOND READING THIS 19 DAY OF APRIL, 2022.
MAYOR
ATTEST:
CITY SECRETARY
APPROVED AS TO FORM AND LEGALITY:
_____________________________________
CITY ATTORNEY
PUBLISHED:
EFFECTIVE:
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EXHIBIT A
2021 International Energy Conservation Code Complete Edition
Located in the Building Inspections Office
1400 Main St., Suite 250
City of Southlake, Texas
76092
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EXHIBIT B
Amendments to the 2021 International Energy Conservation Code
The following sections, paragraphs, and sentences of the 2021 International Energy Conservation Code
(IECC) are hereby amended as follows: Standard type is text from the IECC. Underlined type is text
inserted. Lined through type is deleted text from IECC. A double (**) asterisk at the beginning of a section
identifies an amendment carried over from the 2018 edition of the code and a triple (***) asterisk identifies
a new or revised amendment with the 2021 code. Section numbers in parenthesis represent the
corresponding numbers of the energy provisions of the 2021 International Residential Code for parallel
amendments.
**Section C102/R102; add Section C102.1.2 and R102.1.2 to read as follows:
C102.1.2 Alternative compliance. A building certified by a national, state, or local accredited energy
efficiency program and determined by the Energy Systems Laboratory to be in compliance with the
energy efficiency requirements of this section may, at the option of the Code Official, be considered in
compliance. The United States Environmental Protection Agency's Energy Star Program certification of
energy code equivalency shall be considered in compliance.
R102.1.2 Alternative compliance. A building certified by a national, state, or local accredited energy
efficiency program and determined by the Energy Systems Laboratory to be in compliance with the
energy efficiency requirements of this section may, at the option of the Code Official, be considered in
compliance. The United States Environmental Protection Agency's Energy Star Program certification of
energy code equivalency shall be considered in compliance. Regardless of the program or the path to
compliance, each 1- and 2-family dwelling shall be tested for air and duct leakage as prescribed in
Section R402.4.1.2 (N1102.4.1.2) and R403.3.3 (N1103.3.3) respectively.
(Reason: This amendment is added to allow alternative compliance in accordance with Texas HB 1365,
78th Legislature. Codified in Chapter 388 Texas Building Energy Performance Standards: §388.003(i).
The last sentence to Section R102.1.2 was added to insure that every house is tested in accordance with
the mandatory provisions of the code.)
**Section R202; add the following definition:
DYNAMIC GLAZING. Any fenestration product that has the fully reversible ability to change its
performance properties, including U-factor, solar heat gain coefficient (SHGC), or visible transmittance
(VT).
(Reason: This term is referenced in Section R402.3.2. This definition of DYMANIC GLAZING is also
found in the Commercial provisions of the code.)
***Section R401.2.5 Additional Energy efficiency; deleted in its entirety.
(Reason: The deletion is based on the Complexity of the section and lack of tools to verify compliance
and due to conflict with HB2439, 86th Regular Session)
***Table 402.1.2 Maximum Assembly/Climate Zone items: amend table as follows.
Climate Zone Fenestration
U-Factorf
Ceiling
U-Factor
2 .40 0.26 0.29
3 0.30 0.32 0.26 0.29
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***Table 402.1.3 Insulation/Climate Zone items: amend table as follows.
Climate Zone Fenestration
U-Factor b, i
Ceiling
R-Value
Wood Frame
Wall R-Value
Slab R-Value
& Depth
2 .40 49 42 13 or 0 + 10 0
3 0.30 0.32 49 42 19 or 13+53ci,
0+15
10ci, 2 ft 0
(Reason: Amended table to meet current building techniques, market conditions and product availability.
Amended to avoid conflict between North Texas termite zone and slab R value in code.)
NEW WORDING:
***Section R402.4.1 Building thermal envelope; add section R402.4.1.4 to read as follows
R402.4.1.4 Sampling options for R2 multifamily dwelling units. For buildings with eight or more testing
units that must be tested as required by R402.1.2 or R402.1.3, the greater of seven units or 20 percent of
the testing units in the building shall be tested, including a top floor unit, a ground floor unit, a middle floor
unit, and a unit with the largest testing unit enclosure area. For each tested unit that exceeds the
maximum air leakage rate, an additional three units shall be tested, including a mixture of testing unit
types and locations. Where buildings have fewer than eight testing units, each testing unit shall be
tested.
(Reason: For many multifamily (R2 classifications) projects, it is very costly and time consuming to test
each dwelling unit for projects where there may be dozens of dwelling units in each building. Considering
that the same tradesman generally constructs a building, it is reasonable to deem that construction
practices are consistent and that if a reasonable sampling of units tested pass then all units would pass.
These amendments are in line with the commercial provisions of the commercial 2021 IECC and
RESNET sampling guidelines.)
*** Section R402.4.6 Electrical and Communication outlet boxes. Delete after the first sentence to
read as follows.
***R402.4.6 Electrical and communication outlet boxes (air-sealed boxes). Electrical and communication
outlet boxes installed in the building thermal envelope shall be sealed to limit air leakage between
conditioned and unconditioned spaces. Electrical and communication outlet boxes shall be tested in
accordance with NEMA OS 4 , Requirements for Air-Sealed Boxes for Electrical and Communication
Applications, and shall have an air leakage rate of not greater than 2.0 cubic feet per minute
(0.944 L/s) at a pressure differential of 1.57 psf (75 Pa). Electrical and communication outlet boxes shall
be marked “NEMA OS 4” or “OS 4” in accordance with NEMA OS 4. Electrical and communication outlet
boxes shall be installed per the manufacturer’s instructions and with any supplied components required to
achieve compliance with NEMA OS 4.
(Reason: Allow for alternatives and Avoid requiring proprietaries products.)
***Section C402.5.2 Dwelling and sleeping unit enclosure testing. Added the underlined to read as
follows
C402.5.2 Dwelling and sleeping unit enclosure testing. The building thermal envelope shall be tested in
accordance with ASTM E779. ANSI/RESNET/ICC 380, ASTM E1827 or an equivalent method approved
by the code official. The measured air leakage shall not exceed 0.30 cfm/ft2 (1.5 Us m2) of the testing
unit enclosure area at a pressure differential of 0.2 inch water gauge (50 Pa). Where multiple dwelling
units or sleeping units or other occupiable conditioned spaces are contained within one building thermal
envelope, each unit shall be considered an individual testing unit, and the building air leakage shall be the
weighted average of all testing unit results, weighted by each testing unit's enclosure area. Units shall be
tested separately with an unguarded blower door test as follows:
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1. Where buildings have fewer than eight testing units, each testing unit shall be tested.
2. For buildings with eight or more testing units, the greater of seven units or 20 percent of the
testing units in the building shall be tested, including a top floor unit, a ground floor unit, a middle floor
unit, and a unit with the largest testing unit enclosure area. For each tested unit that exceeds the
maximum air leakage rate, an additional two three units shall be tested, including a mixture of testing unit
types and locations.
(Reason: For many multifamily (R2 classifications) projects, it is very costly and time consuming to test
each dwelling unit for projects where there may be dozens of dwelling units in each building. Considering
that the same tradesman generally constructs a building, it is reasonable to deem that construction
practices are consistent and that if a reasonable sampling of units tested pass then all units would pass.
These amendments are in line with RESNET sampling guidelines.)
***Section R403.3 Ducts; add section R403.3.8 to read as follows
R403.3.8 Sampling options for R2 multifamily dwelling units. For buildings with eight or more testing units
that must be tested as required by R403.3.5, the greater of seven units or 20 percent of the testing units
in the building shall be tested, including a top floor unit, a ground floor unit, a middle floor unit, and a unit
with the largest testing unit floor area. For each tested unit that exceeds the maximum duct leakage rate,
an additional three units shall be tested, including a mixture of testing unit types and locations. Where
buildings have fewer than eight testing units, each testing unit shall be tested.
(Reason: For many multifamily (R2 classifications) projects, it is very costly and time consuming to test
each dwelling unit for projects where there may be dozens of dwelling units in each building. Considering
that the same tradesman generally constructs a building, it is reasonable to deem that construction
practices are consistent and that if a reasonable sampling of units tested pass then all units would pass.
These amendments are in line with the commercial provisions of the commercial 2021 IECC and
RESNET sampling guidelines.)
***Section R403.6 Mechanical Ventilation; add section R403.6.4 to read as follows
R403.6.4 Sampling options for R2 multifamily dwelling units. For buildings with eight or more testing units
that must be tested as required by R403.6.3, the greater of seven units or 20 percent of the testing units
in the building shall be tested, including a top floor unit, a ground floor unit, a middle floor unit, and a unit
with the largest testing unit floor area. For each tested unit that does not meet the minimum ventilation
rate, an additional three units shall be tested, including a mixture of testing unit types and locations.
Where buildings have fewer than eight testing units, each testing unit shall be tested.
(Reason: For many multifamily (R2 classifications) projects, it is very costly and time consuming to test
each dwelling unit for projects where there may be dozens of dwelling units in each building. Considering
that the same tradesman generally constructs a building, it is reasonable to deem that construction
practices are consistent and that if a reasonable sampling of units tested pass then all units would pass.
These amendments are in line with the commercial provisions of the commercial 2021 IECC IECC and
RESNET sampling guidelines.)
***Section R404.1; revised in its entirety to read as follows:
Section R404.1 Lighting equipment (Mandatory). Not less than 75 percent of the lamps in
permanently installed lighting fixtures or not less than 90 75 percent of the permanently installed lighting
fixtures shall contain only high-efficacy lamps.
(Reason: This retains the 2015 language will allow for more flexibility.)
***Section R404.2 Interior Lighting Controls; deleted in its entirety.
(Reason: The deletion is to eliminate confusion as the intent does not reflect what is written.)
***R405.2 Performance-based compliance. Added to underlined to read as follows.
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R405.2 Performance-based compliance. Compliance based on total building performance requires that a
proposed design meets all of the following:
1. The requirements of the sections indicated within Table R405.2.
2. The building thermal envelope greater than or equal to levels of efficiency and solar heat gain
coefficients in Table R402.1.1 or R402.1.3 of the 2009 International Energy Conservation
Code.
3. An annual energy cost that is less than or equal to the annual energy cost of the 2021
standard reference design or 8% less than the annual energy cost of the 2018 standard
reference design. Energy prices shall be taken from a source approved by the code official,
such as the Department of Energy, Energy Information Administration's State Energy Data
System Prices and Expenditures reports. Code officials shall be permitted to require time-of-
use pricing in energy cost calculations.
Exception: The energy use based on source energy expressed in Btu or Btu per square foot
of conditioned floor area shall be permitted to be substituted for the energy cost. The source
energy multiplier for electricity shall be 3.16. The source energy multiplier for fuels other
than electricity shall be 1.1.
(Reason: At the time of the approval of these recommended amendments, software to calculate and
show compliance with section R405 of the 2021 IECC was not available. The underlined amendment
allows an alternative option to show compliance until software is available.)
**TABLE R406.4 (N1106.4) MAXIMUM ENERGY RATING INDEX; amend to read as follows:
TABLE R406.4 (N1106.4) 1
MAXIMUM ENERGY RATING INDEX
CLIMATE ZONE ENERGY RATING INDEX
2 52 63
3 52 63
1 This table is effective until August 31, 2022.
TABLE R406.4 (N1106.4) 2
MAXIMUM ENERGY RATING INDEX
CLIMATE ZONE ENERGY RATING INDEX
2 52 59
3 52 59
2 The table is effective from September 1, 2022 to August 31, 2025.
TABLE R406.4 (N1106.4) 3
MAXIMUM ENERGY RATING INDEX
CLIMATE ZONE ENERGY RATING INDEX
2 52 57
3 52 57
3 The table is effective from September 1, 2025 to August 31, 2028.
TABLE R406.4 (N1106.4) 3
MAXIMUM ENERGY RATING INDEX
CLIMATE ZONE ENERGY RATING INDEX
2 52 55
3 52 55
4 This table is effective on or after September 1, 2028.
(Reason: The tables reflect the values and timetable set forth in HB 3215, 87th Regular Session Codified
in Chapter 388 Texas Building Energy Performance Standards: §388.003.)
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***Section R408 ADDITIONAL EFFICIENCY PACKAGE OPTIONS; deleted in its entirety.
(Reason: The deletion is based on the omission of R401.2.5 and R408 no longer applies and due to
conflict with HB2439, 86th Regular Session.)
NOTE: HB 3215 was signed into law by the Governor on June 14, 2021 as part of the 87th Regular
Session Codified in Chapter 388 Texas Building Energy Performance Standards: §388.003 (i), (j), and
(k). HB 3215 now allows a Home Energy Rating System Index (ex. HERS Index) utilizing
ANSI/RESNET/ICC Standard 301 (as it existed on January 1, 2021) shall be considered in compliance with
State law provided that:
o The home includes compliance with the Mandatory requirements of 2018 IECC Section
R406.2.
o The home includes compliance with Building thermal envelope provisions of Table
R402.1.2 or Table R402.1.4 of the 2018 IECC
END