Energy Code Feasibility Study Texas: Multifamily ASHRAE/COMcheck Paths and When to Model First

If you are building multifamily in Texas, the expensive question is not "where do I get a COMcheck?" It is which energy-code path your permit address actually enforces, and whether envelope or HVAC moves are worth it before anyone buys modeling hours. An energy code feasibility study answers that with your plans, not with a generic checklist.

This page is the Texas study door. For the national explainer, see feasibility study for energy code. For the Texas commercial code-path deep dive (ASHRAE 90.1 editions, COMcheck, and why mid-rise is not HERS-first), see ASHRAE COMcheck Texas multifamily. For how energy modeling works on apartment buildings in general, see multifamily energy modeling. HERS rating multifamily describes a dwelling-unit rating path used heavily outside Texas. It is here only as a contrast: Texas mid-rise and mixed-use commercial compliance is not HERS-first.

What a Texas Energy Code Feasibility Study Actually Compares

On a Texas multifamily study, the comparison is the set of buildable packages the authority having jurisdiction (AHJ) will accept at the permit address. Typical levers:

• The statewide 2015 IECC floor versus a newer IECC a local jurisdiction has adopted. Large cities can sit ahead of the state floor.
• IECC commercial provisions versus the ASHRAE 90.1 alternative the adopted edition references
• Whether the whole building is commercial, or whether a low-rise residential scope and commercial areas split
• Envelope and HVAC packages that move construction dollars once that path is locked
• The compliance form the department will accept, usually a COMcheck, before anyone prices modeling hours against the wrong year

You are not buying a brochure. You are buying a ranked set of buildable paths tied to your unit mix, building height, mixed-use split, and the code edition adopted at the permit address.

Why Texas Needs the Study Before COMcheck or ASHRAE Hours

Mid-rise, high-rise, and most mixed-use buildings land on IECC commercial or ASHRAE 90.1, usually documented with a COMcheck, not on a HERS-first dwelling-unit path. Statewide, the floor is still the 2015 IECC for commercial construction and for residential construction other than single-family. The State Energy Conservation Office (SECO) adopted that edition under Texas Health and Safety Code Chapter 388, effective November 1, 2016. Local jurisdictions may adopt a newer IECC. Confirm the adopted edition and the compliance form with the AHJ before modeling.

Under the IECC, a residential building is a one- and two-family dwelling, a townhouse, or a Group R-2, R-3, or R-4 building three stories or less above grade plane. Taller buildings are commercial. A four-story apartment building, a mid-rise, a high-rise, and most mixed-use buildings with retail or amenity the AHJ classifies as nonresidential land on the commercial chapter. That split is a study input. Guessing it after glass and HVAC are bought is an expensive rewrite.

Buying COMcheck or ASHRAE modeling hours before you lock the edition, the commercial-versus-residential split, and the envelope or HVAC package is how teams:

• Run the software on the wrong IECC or ASHRAE year
• Force a HERS narrative onto a four-story commercial building the AHJ will not accept that way
• Freeze glazing or HVAC that a cheaper compliant package did not need
• Treat the compliance-report fee as the budget problem when path choice moves much larger construction dollars

Order that protects both the permit set and the pro forma:

1. Confirm the adopted IECC edition at the permit address, state minimum or a local adoption
2. Split IECC commercial or ASHRAE 90.1 from any three-story-or-less residential scope with the code official
3. Compare envelope and HVAC packages on your drawings against that locked path
4. Buy ASHRAE modeling or COMcheck documentation hours against the locked path

Edition pairings (which ASHRAE 90.1 year follows which IECC) and what a COMcheck report contains live on the code-path page. See ASHRAE COMcheck Texas multifamily. This page is the decision that comes before those hours. For what the model is doing once the path is locked, see multifamily energy modeling.

Proof From ECC Studies (Method, Not Invented Texas Quotes)

ECC does not publish a Texas dollar-per-square-foot average, and we do not have a Texas COMcheck invoice to present as your number. We cite other studies as proof of method, and we label them that way. Massachusetts Stretch studies and New York ECCCNYS or NYStretch studies answer different code questions. Do not copy those ceilings into a Texas filing.

On our 267-unit Cromwell, CT study (CS68), two buildings up to six stories (272,036 square feet) were filed under the 2022 Connecticut State Building Code on IECC commercial provisions, using ASHRAE 90.1-2019 Appendix G. The recommended all-electric tier came in at about $35.23 per square foot net and captured a $1,500 per unit Energize CT incentive ($400,500) that more than paid for the envelope upgrades on that path, including R-5 continuous exterior wall insulation and an R-19 spray-foam roof. Those figures are Connecticut commercial-code outcomes, not Texas invoices. They show the order: lock the ASHRAE path, rank the packages, then document the winner.

On a 112-unit Revere, MA study (CS57), a seven-story mixed-use building kept dwelling units on a Massachusetts Stretch HERS path. The recommended ductless package landed at about $42.52 per square foot net. The same study still called for a COMcheck report for common and support areas, plus ASHRAE 62.1 ventilation calculations and lighting power density calculations. Those figures are Massachusetts outcomes, not Texas invoices. They show why mixed-use paperwork splits matter before you buy modeling hours. Do not copy that HERS ceiling into a Texas commercial filing.

Those examples are why a Texas-specific study page exists separately from the general feasibility study for energy code, from the Massachusetts and New York study doors, and from the Texas commercial code-path article. The product here is path economics on your drawings.

State Floor vs Local IECC vs "Just Buy the COMcheck"

State floor. For commercial construction, and for residential construction other than single-family, the statewide minimum is still the 2015 IECC (SECO, Texas Health and Safety Code Chapter 388, effective November 1, 2016). Single-family construction follows a different adoption. This page is not that door. A statewide summary is not the filing target.

Local adoption. Jurisdictions may adopt a newer IECC. Large cities can sit ahead of the state floor. The commercial code-path page already notes that a 2025 legislative analysis of SECO adoption authority recorded Austin, Houston, Dallas, and San Antonio moving to 2021 standards, and that SECO has taken comment on the 2024 IECC without replacing the statewide 2015 minimum. Climate zone at the permit address changes envelope tables inside the same edition. The ASHRAE 90.1 year follows the IECC edition the city adopted. Verify the pairings with the AHJ. The list to check lives on ASHRAE COMcheck Texas multifamily.

COMcheck and ASHRAE documentation execute the path you already chose. A COMcheck proves a design. It does not rank designs. HERS rating work, described in HERS rating multifamily, is the wrong first assumption for a Texas mid-rise or mixed-use commercial filing.

If the path is already locked and you need ASHRAE modeling or a COMcheck for permit, see ECC services. If design is still flexible, start with a free feasibility study.

What You Walk Away With

A useful Texas study should leave the GC, architect, and ownership aligned on:

• Whether the permit address is on the 2015 state floor or a newer local IECC
• Whether the filing is IECC commercial or ASHRAE 90.1, and which portions (if any) stay on a residential chapter
• Recommended envelope and HVAC package, and the runner-up, against that locked path
• The compliance form the AHJ expects, usually a COMcheck
• Clear next step: freeze the path, then buy modeling and COMcheck hours

ECC feasibility studies for qualifying multifamily work are offered at no cost. Soft handoff only: use /freefeasibility when you want the study, and /services when the path is locked and you need ASHRAE modeling, COMcheck, or related permit paperwork.

Bottom Line

An energy code feasibility study in Texas compares the adopted IECC edition (state floor or a local adoption), IECC commercial versus ASHRAE 90.1, and related envelope or HVAC packages on your drawings so construction cost and compliance scope are chosen before COMcheck or ASHRAE modeling hours. Mid-rise, high-rise, and most mixed-use buildings are not a HERS-first problem. Confirm the adopted path at the permit address. Rank the packages. Then buy the documentation work that executes the winner.