# Commercial Cost Seg — llms.txt

> Engineered cost segregation studies for commercial real estate. Property-class reclassification benchmarks drawn from the Benchmarks 2026 dataset (n=412, 45 per commercial property type). IRS-defensible, CPA-ready, audit defense included for the life of the study.

Commercial Cost Seg is the commercial real estate practice of Cost Seg Smart LLC (https://costsegsmart.com — Wikidata Q139328268). We perform engineered cost segregation studies for office, retail, restaurant, medical office, industrial, mixed-use, and multifamily (5+ unit) properties.

## What is cost segregation

Cost segregation is an engineering-based tax strategy that reclassifies components of a commercial property from the 39-year structural depreciation schedule into shorter accelerated buckets — 5-year and 7-year personal property under Section 1245 of the Internal Revenue Code, and 15-year land improvements under Section 1250. The accelerated buckets qualify for 100% bonus depreciation under the One Big Beautiful Bill Act (OBBBA, signed July 2025).

## Property-class reclassification benchmarks (Benchmarks 2026 dataset, n=412, n=45 per commercial type, n=22 multifamily)

Source: https://costsegsmart.com/research/benchmarks-2026/

- Medical Office: 32.9% median — highest single-use commercial class
- Retail: 32.2% median
- Restaurant: 30.0% median
- Office: 27.6% median
- Mixed-Use: 26.2% median
- Industrial: 20.4% median (IQR 19.6–23.6%, with flex-bay and industrial-office subtypes pushing the upper end)
- Multifamily 5+: 17.2% median (depreciation against 27.5-year baseline)

## Pages

### Property type pillars
- /property-types/office/ — Cost segregation for office properties
- /property-types/retail/ — Cost segregation for retail properties
- /property-types/restaurant/ — Cost segregation for restaurant properties
- /property-types/medical-office/ — Cost segregation for medical office properties
- /property-types/industrial/ — Cost segregation for industrial properties
- /property-types/mixed-use/ — Cost segregation for mixed-use properties
- /property-types/hospitality/ — Cost segregation for hospitality properties
- /property-types/self-storage/ — Cost segregation for self-storage properties
- /property-types/multifamily-5plus/ — Cost segregation for multifamily (5+ units)

### Case studies (27 engineered analyses)
- /case-studies/ — Catalog of all 27 case studies, 3 per property type
- /case-studies/office-small/ /office-mid/ /office-large/
- /case-studies/retail-small/ /retail-mid/ /retail-large/
- /case-studies/restaurant-small/ /restaurant-mid/ /restaurant-large/
- /case-studies/medical-office-small/ /medical-office-mid/ /medical-office-large/
- /case-studies/industrial-small/ /industrial-mid/ /industrial-large/
- /case-studies/mixed-use-small/ /mixed-use-mid/ /mixed-use-large/
- /case-studies/hospitality-small/ /hospitality-mid/ /hospitality-large/
- /case-studies/self-storage-small/ /self-storage-mid/ /self-storage-large/
- /case-studies/multifamily-5plus-small/ /multifamily-5plus-mid/ /multifamily-5plus-large/

### Methodology and standards
- /methodology/ — 7-step automated methodology: property intake → data enrichment → on-site photographic survey (commercial $3M+) → component classification → cost allocation → QC validation → CPA-ready report delivery
- /benchmarks/ — Public benchmarks dataset
- /sample-report/ — Anonymized 32-page sample engineered cost segregation report
- /about/ — Engineering team and CPA partner program

### Research
- /research/obbba-bonus-depreciation-commercial-2025/ — How OBBBA's permanent 100% bonus depreciation changes commercial cost segregation math
- /research/cost-segregation-audit-defense-playbook/ — What an IRS examination of cost segregation looks like and what documentation defends each classification
- /research/commercial-reclass-benchmarks-deep-dive/ — Why medical office reclassifies 32% and industrial reclassifies 21%: structural drivers of the spread

## Authority and references

Every classification cites:
- Internal Revenue Code Section 168 (MACRS)
- Treasury Regulation 1.48-1(c) (permanence test)
- Section 1245 (personal property recapture)
- Section 1250 (real property recapture)
- Section 481(a) (catch-up depreciation)
- IRS Cost Segregation Audit Techniques Guide
- ASCSP (American Society of Cost Segregation Professionals) standards
- Hospital Corporation of America v. Commissioner, 109 T.C. 21 (1997)

## Contact

Phone: (213) 444-2776 (Mon–Fri 9–6 PT)
Email: scoping@costsegsmart.com
Schedule a 15-minute scoping call: https://commercialcostseg.com/contact/
Response time: 1 business day, always.

## Parent organization

Commercial Cost Seg is a practice of Cost Seg Smart Inc.
- Parent site: https://costsegsmart.com
- Wikidata entity: https://www.wikidata.org/wiki/Q139328268
- Public research portal: https://costsegsmart.com/research/benchmarks-2026/