- The TN-BC exam covers 15 named content areas, from Estimating and Plan Reading to OSHA Safety.
- Estimating and Plan Reading and Concrete and Concrete Reinforcement are tied as the largest domains at 15% each.
- The open-book exam has 100 questions, a 5-hour limit, and requires a 73% passing score.
- References include the 2021 IBC, 2018 IRC, the Study Guide for Commercial Building Contractor (2024), and OSHA 29 CFR Part 1926.
Why the 15 Domains Matter
The Tennessee Commercial (BC-B) Contractor Examination is not a generic construction quiz. It is a structured, 15-domain test built by the Tennessee Board for Licensing Contractors to confirm that a candidate can safely and competently run full commercial building projects. If you're targeting the Commercial (BC-B) classification specifically - rather than the broader combined BC exam or the limited small-commercial classification - every one of these 15 domains is fair game, and understanding how they're weighted changes how you should spend your prep time.
This guide breaks down all 15 content areas exactly as the Board defines them, explains what each one actually tests, and shows you where to concentrate effort. For a broader look at how to structure your entire prep plan, pair this with the TN-BC Study Guide 2026: How to Pass on Your First Attempt.
Exam Format and Registration Facts
Before diving into content, it helps to know exactly what you're walking into. The Commercial (BC-B) exam is open-book and computer-based, delivered through Prov either at a test center or remotely via Examroom. It consists of 100 multiple-choice questions, allows a 5-hour testing window, and requires a 73% score to pass. Prov has administered exam appointments since July 1, 2026, and the current Prov bulletin is dated July 13, 2026.
- Fee: $53 per attempt, paid to Prov
- Format: Open-book, multiple-choice, computer-based
- Time limit: 5 hours for 100 questions
- Passing score: 73%
- References allowed: 2021 International Building Code, 2018 International Residential Code, Study Guide for Commercial Building Contractor (2024), and OSHA 29 CFR Part 1926
Because it's open-book, the exam rewards candidates who know exactly where to find an answer in their references quickly - not just those who memorize code sections. Tab your books by domain before test day. For the precise breakdown of what "73%" means in raw question terms, see TN-BC Passing Score 2026: Exactly What You Need to Pass.
The Two Heaviest Domains
Two domains carry the most weight on the exam: Estimating and Plan Reading and Concrete and Concrete Reinforcement, tied at 15% each. Together they represent nearly a third of the entire exam, which makes them the natural starting point for any serious study plan.
Domain 1: Estimating and Plan Reading
Tests your ability to interpret commercial construction drawings, take off quantities, and build accurate cost estimates from plan sets.
- Reading dimensions, elevations, and symbols on commercial drawing sets
- Quantity takeoffs for materials and labor
- Recognizing plan discrepancies and specification callouts
Domain 5: Concrete and Concrete Reinforcement
Covers mix design basics, placement, curing, formwork, and reinforcing steel requirements for commercial structures.
- Concrete mix selection and slump/curing considerations
- Reinforcing steel placement, laps, and cover requirements
- Formwork design and stripping timing
If you only had time to master two domains, these would be them. Everything else on the exam builds on the ability to read a set of plans correctly and understand how a commercial building's concrete structure comes together.
All 15 Content Areas Explained
Here is every domain the Board tests, in order, with what candidates need to walk in knowing.
Domain 2: General Code
Broad familiarity with the structure and application of the 2021 IBC and 2018 IRC as they apply to commercial projects, including permitting basics and occupancy classifications.
- How to navigate the IBC's table of contents under time pressure
- Occupancy group and construction type basics
Domain 3: Sitework
Site preparation, grading, excavation, erosion control, and utility rough-in sequencing before vertical construction begins.
- Cut/fill and compaction concepts
- Erosion and sediment control requirements
Domain 4: Footings and Foundations
Foundation types, footing sizing logic, waterproofing, and how foundation systems interact with soil conditions on commercial sites.
- Footing depth and bearing considerations
- Foundation waterproofing and drainage
Domain 6: Masonry
Concrete masonry units, brick veneer, mortar types, and reinforcement in masonry walls for commercial structures.
- CMU wall reinforcement and grouting
- Mortar type selection by application
Domain 7: Carpentry
Rough and finish framing concepts as applied to commercial-scale wood and light-gauge construction.
- Framing member sizing logic
- Blocking, bracing, and fastening schedules
Domain 8: Doors, Windows, and Stairs
Installation tolerances, fire-rating considerations, and code-required dimensions for openings and egress components.
- Fire-rated door and frame assemblies
- Stair rise/run and handrail code minimums
Domain 9: Interior Finish
Drywall, ceiling systems, flooring, and interior trim as they relate to commercial finish-out schedules.
- Fire-rated assembly finish requirements
- Ceiling grid and acoustic system basics
Domain 10: Structural Steel
Steel framing systems, connections, and erection sequencing for commercial buildings.
- Bolted vs. welded connection basics
- Steel erection sequencing and bracing
Domain 11: Roofing, Siding, and Insulation
Commercial roofing systems, exterior cladding, and building envelope insulation requirements.
- Low-slope vs. steep-slope roofing assemblies
- Continuous insulation and vapor barrier placement
Domain 12: Plumbing Concepts
General awareness of commercial plumbing systems as a general contractor must coordinate them, not licensed-trade depth.
- Rough-in coordination with structure
- Basic fixture and drainage requirements
Domain 13: HVAC Concepts
Mechanical system coordination points a commercial GC must understand to sequence trades correctly.
- Ductwork routing and clearances
- Coordination between structural and mechanical trades
Domain 14: Electrical Concepts
General electrical coordination knowledge for commercial GCs overseeing licensed electrical subcontractors.
- Panel and conduit routing coordination
- Basic code awareness for electrical rough-in sequencing
Domain 15: OSHA Safety
Jobsite safety requirements drawn from OSHA 29 CFR Part 1926, covering fall protection, excavation safety, and general jobsite hazard controls.
- Fall protection thresholds and requirements
- Excavation and trenching safety rules
Grouping the Domains for Study
Rather than treating all 15 domains as equal, it helps to think in tiers. Estimating and Plan Reading and Concrete and Concrete Reinforcement sit at the top. A second tier of structurally-central domains - General Code, Footings and Foundations, Structural Steel, and OSHA Safety - deserves heavy attention because they touch nearly every commercial project regardless of building type. The remaining domains round out the trade-specific and finish-related knowledge a commercial contractor needs to coordinate, even without performing the work directly.
| Tier | Domains | Why It Matters |
|---|---|---|
| Top Weight | Estimating and Plan Reading; Concrete and Concrete Reinforcement | Tied as the largest domains at 15% each |
| Structural Core | General Code; Footings and Foundations; Structural Steel; OSHA Safety | Foundational to every commercial project regardless of use type |
| Trade Coordination | Plumbing Concepts; HVAC Concepts; Electrical Concepts | GC-level coordination knowledge, not licensed-trade depth |
| Envelope & Finish | Masonry; Carpentry; Doors, Windows, and Stairs; Interior Finish; Roofing, Siding, and Insulation; Sitework | Rounds out full-project knowledge from site to finish |
Key Takeaway
Spend your earliest and longest study blocks on Estimating and Plan Reading and Concrete and Concrete Reinforcement, then layer in the structural-core domains before finishing with trade-coordination and finish-level content.
Who Actually Sits for This Exam
The Commercial (BC-B) classification is aimed at contractors bidding and running full commercial-building projects - office buildings, retail construction, multi-family and mixed-use structures, and similar work generally at $25,000 or more in project value, which is where Tennessee contractor licensing requirements typically apply. Candidates usually come from superintendent, project manager, or estimator backgrounds where they've already touched several of these 15 domains on the job but need to formalize that knowledge for the exam.
Passing the exam is only one piece of licensure. Applicants must also pass Tennessee Business and Law, document relevant experience and a reference, demonstrate financial capacity through a financial statement or the Board-approved surety-bond route, and carry liability insurance plus workers' compensation coverage or an approved exemption. The full breakdown of eligibility is covered in TN-BC Requirements 2026: Eligibility, Prerequisites & How to Qualify, and the complete fee picture - including the $250 initial application fee and $200 two-year renewal - is laid out in TN-BC Certification Cost 2026: Complete Pricing Breakdown.
If you're still weighing whether the license fits your career path, Is the TN-BC Certification Worth It? Complete ROI Analysis 2026 and TN-BC Jobs both go into the practical upside of holding a Commercial (BC-B) license in Tennessee's construction market.
Scheduling Your Review Around Domain Weight
A domain-driven schedule works better than a generic one because it puts your limited hours where the exam actually rewards them. Since Estimating and Plan Reading and Concrete and Concrete Reinforcement together account for the largest share of questions, they should anchor your first two weeks of prep, not get squeezed in near the end.
Estimating and Plan Reading
- Practice full quantity takeoffs from sample commercial plan sets
- Tab your Study Guide for Commercial Building Contractor (2024) by takeoff category
Concrete and Concrete Reinforcement
- Review mix design, curing, and reinforcement placement rules
- Cross-reference 2021 IBC concrete chapter sections in your open-book copy
Structural Core Domains
- Footings and Foundations, Structural Steel, General Code, OSHA Safety
- Work practice questions pulling from OSHA 29 CFR Part 1926
Trade Coordination and Finish Domains
- Plumbing, HVAC, and Electrical Concepts at a coordination level
- Masonry, Carpentry, Doors/Windows/Stairs, Interior Finish, Roofing/Siding/Insulation, Sitework
Run a full-length timed practice exam once you've covered all 15 domains, aiming to simulate the 5-hour, 100-question format as closely as possible. For a deeper look at how difficult candidates find the exam in practice, see How Hard Is the TN-BC Exam? Complete Difficulty Guide 2026, and check TN-BC Exam Dates 2026: Testing Windows, Deadlines & Scheduling before locking in your test date. You can also work through domain-specific practice questions on the main practice test site to see how these topics actually get phrased.
For a condensed, last-mile review right before test day, the TN-BC Cheat Sheet 2026: One-Page Review of Must-Know Facts summarizes the highest-yield facts across all 15 domains in one place. And if you want independent confirmation of how your prep is tracking against real outcomes, TN-BC Pass Rate 2026: What the Data Shows is worth reviewing alongside your study plan on this site.
Frequently Asked Questions
There are 15 content areas, ranging from Estimating and Plan Reading through OSHA Safety, covering the full scope of commercial building construction.
Estimating and Plan Reading and Concrete and Concrete Reinforcement are tied as the largest domains at 15% each, making them the top study priority.
Yes. Candidates may use the 2021 International Building Code, 2018 International Residential Code, Study Guide for Commercial Building Contractor (2024), and OSHA 29 CFR Part 1926 during the 5-hour, 100-question exam.
The Plumbing Concepts, HVAC Concepts, and Electrical Concepts domains test coordination-level knowledge appropriate for a general contractor overseeing licensed subcontractors, not licensed-trade depth.
Exam scores are typically valid for two years, so plan your remaining licensure steps, including Tennessee Business and Law, within that window.