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How to Meet the Latest Texas Energy Efficiency Codes

Since November 2016, builders and archi­tects in Texas must comply with the 2015 Inter­na­tion­al Energy Con­ser­va­tion Code (IECC) for both com­mer­cial and res­i­den­tial con­struc­tion. Texas adopted the 2015 IECC to lessen energy use and costs to busi­ness­es and home­own­ers. In fact, the ICC reports an increase in energy effi­cien­cy by 18 percent in res­i­den­tial and 26 percent in com­mer­cial struc­tures after imple­men­ta­tion of the IECC 2015 standards over the previous IECC 2009 standards.

By requiring the 2015 IECC latest energy codes, Texas is leading the way toward reducing CO2 emissions and advancing the goal of the World Green Building Councils (GBCs) to achieve net zero carbon by 2030 for all new con­struc­tion. Builders and archi­tects in Texas must meet the challenge to build and design all projects according to the 2015 IECC codes.

Com­pli­ance with the codes ensures achieve­ment of the highest standards of energy effi­cien­cy, safety, and dura­bil­i­ty for today’s building projects in Texas.

Building Projects Must Comply with Both State and Local Energy Codes

All com­mer­cial and res­i­den­tial projects greater than three stories must meet energy effi­cien­cy require­ments according to the American Society of Heating, Refrig­er­at­ing, and Air-Con­di­tion­ing Engineers (ASHRAE 90.1) or the 2015 IECC codes and standards.

The design of the struc­tures must also consider the total building per­for­mance, including air leakage, mechan­i­cal systems, water heaters, lighting, and metering.

Builders and archi­tects must not only comply with the 2015 IECC codes, but also those of their local juris­dic­tions. In Texas, local juris­dic­tions can amend and adopt local energy code, so long as the modified code is not less stringent than the code adopted by the state.

To avoid confusion between local and state codes, builders and archi­tects should begin designing all projects to the 2015 IECC standards, then implement addi­tion­al local requirements.

Building Envelope Options for Exterior Walls

For the building envelope of a com­mer­cial building, there are three energy code com­pli­ance options typically used by architects.

  1. Insu­la­tion component method: Building a structure that meets the 2015 IECC and ASHRAE 90.1 standards for energy effi­cien­cy requires achieving specified R‑values for con­tin­u­ous insu­la­tion around a building’s envelope. The ASHRAE Standard 90.12013 defines con­tin­u­ous insu­la­tion as insu­la­tion that is uncom­pressed and con­tin­u­ous across all struc­tur­al members without thermal bridges other than fasteners and service openings. Section C402.1.3 of the 2015 IECC specifies the amount of insu­la­tion required for different opaque wall types (mass walls, metal buildings, metal framed, and wood framed).
  2. Thermal con­duc­tiv­i­ty component method: Section C402.1.4 general pre­scrip­tive of the IECC 2015 specifies the maximum cumu­la­tive U‑Factor (or thermal con­duc­tiv­i­ty) of all the com­po­nents in a wall assembly for different opaque wall types (mass walls, metal buildings, metal framed, and wood framed and other). The code also provides a table for cal­cu­lat­ing the U‑Factor of cold-formed steel stud wall systems with different levels of cavity insulation.
  3. Component Per­for­mance Alter­na­tive method: Section C402.1.5 of the general pre­scrip­tive of the IECC 2015 specifies that the weighted average of U‑Factors of the envelope assem­blies, based on surface area, is less than the weighted average maximum U‑Factor permitted in IECC Table C402.1.4. The component per­for­mance alter­na­tive method allows designs to increase per­for­mance in one area of building to com­pen­sate for degraded per­for­mance in other areas. Ver­i­fi­ca­tion of com­pli­ance for this option is typically done using COMcheck software.

Con­tin­u­ous Insu­la­tion Options for Exterior Walls

The IECC includes a climate zone map which divides the country into eight zones: zone one is warmest and zone eight is the coldest. The three major climate zones in Texas are two, three, and four. Each zone is assigned a building envelope insu­la­tion require­ments for different wall systems using the insu­la­tion component R‑value method. 

The different wall systems include wood-framing, metal framings, metal building, and mass walls (concrete and masonry). Mass walls are excep­tion­al­ly energy-efficient because they can absorb and release energy over time. 

Therefore, the required R‑value for mass walls is lower (less insu­la­tion require­ment) than required R‑value for light framed or steel wall assemblies.

Bautex Wall System Helps Builders Meet the Latest Texas Energy Effi­cien­cy Codes

The easy to install Bautex Wall System, man­u­fac­tured in Central Texas, helps con­trac­tors and archi­tects meet the challenge of building according to the latest Texas energy effi­cien­cy codes without over­spend­ing on materials or labor.

The Bautex Wall system exceeds the 2015 IECC require­ments for con­tin­u­ous insu­la­tion, thermal mass, and an air barrier for all climate zones in Texas. The Bautex Wall System is also a four-hour load-bearing fire-rated wall that provides excellent fire pro­tec­tion. Please visit Bautex Wall System learn more on meeting the latest Texas energy effi­cien­cy codes.