Disclaimer

CrewCalcs is a suite of free, automated calculation and sizing tools for the U.S. building trades, operated by ATC Group. This Disclaimer explains what CrewCalcs results are and, just as importantly, what they are not. It applies to every calculator, converter, chart, methodology note, and other content on crewcalcs.com (the “Service”), and it forms part of our Terms of Service. Capitalized terms not defined here have the meaning given in the Terms.

1. Results are estimates for planning only

CrewCalcs is a computational aid intended to help qualified tradespeople and professionals check, size, or convert a number quickly. Its outputs depend entirely on the accuracy of the inputs you provide and on assumptions that may not fit your specific project, site, materials, equipment, or local conditions. A result may be wrong for your situation even when the calculation itself is performed correctly.

2. No professional relationship

ATC Group and CrewCalcs are not a licensed engineering, architecture, or contracting firm, and we do not employ or provide licensed professionals to you through the Service. Using CrewCalcs does not create an engineer-client, architect-client, contractor-client, or any other professional relationship between you and ATC Group. No output is a sealed, stamped, or certified engineering calculation, and no one at ATC Group reviews, approves, or takes professional responsibility for your project.

3. Verify against your adopted code and your AHJ

Building, mechanical, electrical, plumbing, fuel-gas, and structural codes are adopted, and frequently amended, locally. The edition and amendments enforced by your Authority Having Jurisdiction (AHJ) may differ from the general methods CrewCalcs uses. Before you design, purchase, install, or build anything, you must:

• independently verify every input and every result;
• confirm the result against the specific code edition and local amendments adopted by your AHJ; and
• have a licensed professional review, verify, and, where required by law, seal or stamp any design or decision before it is used in actual construction.

4. Assumption of risk and your responsibility

Construction and trade work (including HVAC, electrical, gas, plumbing, and structural work) carries an inherent risk of property damage, serious injury, and death. You acknowledge and agree that:

• you are the responsible professional or party for any design, purchasing, installation, or construction decision you make;
• you knowingly assume all risk arising from your use of, or reliance on, any CrewCalcs result; and
• you will not rely on a CrewCalcs result as the sole basis for any decision that affects health, safety, or code compliance.

5. How we compute

CrewCalcs computes from published engineering equations and physical properties, and it references code and standard provisions by section number and edition. It does not reproduce copyrighted code tables or text. Physical and thermodynamic properties are generated from open sources and validated against published anchor values. Some tools rely on documented engineering assumptions (for example, envelope U-values or diversity factors) that are defensible planning defaults, not code requirements. For the full method, sources, and code editions behind each tool, see our Methodology page.

6. No affiliation or endorsement

CrewCalcs is independent. References to codes, standards, and methods, including the NEC® / NFPA 70®, the International Codes® (ICC), ASHRAE®, ACCA® and its Manual J® / Manual D® / Manual N® procedures, AISC®, ACI®, and ASCE® standards, are descriptive only. Those names, standards, and marks are the property of their respective owners. Their use here does not imply that CrewCalcs is affiliated with, sponsored by, endorsed by, approved by, or certified by any standards organization, code body, or manufacturer. CrewCalcs is not “ACCA-approved,” is not “powered by” any organization’s method, and does not certify code compliance.

7. No warranty; limited liability

The full disclaimer of warranties, the limitation of liability (including the liability cap and its exceptions), your indemnification obligations, and the binding-arbitration and class-action-waiver provisions that govern your use of CrewCalcs are set out in our Terms of Service, which you should read in full. This Disclaimer supplements, and does not replace, those terms.

8. Contact

Think a number looks off? We treat correctness as the product. Tell us and we will check it. For questions about this Disclaimer or a specific result, contact legal@crewcalcs.com.