What the 403A exam is
General Carpenter (trade code 403A) is a non-compulsory trade in Ontario under the Building Opportunities in the Skilled Trades Act, 2021. Skilled Trades Ontario has set the apprenticeship at 7,200 hours: 6,480 hours on the job and 720 hours of in-school training, about four years in total.
When you finish your apprenticeship, or are approved through a Trade Equivalency Assessment, you write the certifying exam. Passing it leads to your Certificate of Qualification (C of Q) from Skilled Trades Ontario. Because the trade is non-compulsory, the certificate does not have to be renewed. In Ontario the trade is part of the Interprovincial Red Seal Program under the title Carpenter, and the Red Seal Carpenter exam is the national standard for the trade.
| Part of the exam | What to expect |
|---|---|
| Questions | 100 multiple-choice questions on the Red Seal Carpenter exam |
| Options | Four choices, exactly one correct, with no trick questions |
| Writing time | Four hours |
| Pass mark | 70% |
| Supplied at the exam | A formula sheet, an acronym list, and a calculator if you need one |
| Language | English or French in Ontario |
| If you do not pass | In Ontario, a 30-day waiting period before you can rewrite, and the exam fee is paid again |
The Red Seal program says that for this trade 5 to 15% of questions test knowledge and recall, 75 to 85% test procedures and application, and less than 10% test critical thinking, such as working through a material takeoff. Four hours for 100 questions gives you 2.4 minutes a question. Always check the letter for your own sitting for details.
How the exam is weighted
Red Seal exam questions come from the Red Seal Occupational Standard for the trade. The official exam breakdown gives each major work activity a set number of questions. Our seven sections follow the same activities, and our 100-question mock exams use the same weighting.
| Major work activity | Red Seal questions | What it covers |
|---|---|---|
| A. Common occupational skills | 12 | Tools and equipment, safety, scaffolds and ladders, rigging and hoisting, communication and mentoring |
| B. Planning and layout | 14 | Drawings and scales, organizing work, levels and transits, squaring, takeoffs |
| C. Concrete work | 16 | Formwork, shoring, ties and bracing, placing and curing concrete, volumes |
| D. Framing | 20 | Floor, deck, wall, roof and ceiling systems, rafters and board feet |
| E. Exterior finishing | 14 | Exterior doors and windows, roofing, siding and flashing |
| F. Interior finishing | 14 | Wall and ceiling finishes, flooring, interior doors, trim and stairs |
| G. Renovations | 10 | Temporary support, excavation near existing buildings, repairs and alterations |
Calculations you should be fast at
The Red Seal formula sheet for Carpenter gives pi as 3.14 and lists area, area of a circle and triangle, circumference, the Pythagorean theorem, total rise and total run of a rafter, and the volume of a box and a cylinder. It does not tell you which one to use. Practise these until they feel automatic, and carry your units through every step:
- Squaring and rafters. 3-4-5 and its multiples, rafter line length from run and rise, total run = span / 2, and total rise = total run / unit run x unit rise.
- Concrete. Volume in cubic metres, then cubic yards (1 yd3 = 0.765 m3, or divide cubic feet by 27), round piers with pi x r squared x h, and a waste allowance.
- Lumber. Board feet = thickness (in.) x width (in.) x length (ft) / 12, and stud, joist and rafter counts from the on-centre spacing.
- Stairs. Number of risers and unit rise from the total rise, one fewer tread than risers, and total run.
- Layout. Scale drawings, height of instrument and rod readings, slope in percent, areas and perimeters for sheathing, drywall and trim.
Safety questions and the law
Safety is part of every activity on the exam. Our safety questions use Ontario's construction projects regulation (O. Reg. 213/91) and the Occupational Health and Safety Act, and each explanation names the section: fall protection and guardrails, ladders, scaffolds, formwork and shoring, rigging, overhead power lines and excavations. Building code values differ by province and change with each code edition, so where a question depends on a code value, use the code information for your sitting and your drawings.
How to prepare
Start with the official Red Seal self-assessment and the exam breakdown to find your weaker areas. Use the occupational standard, not only your college notes, because the exam covers the full scope of the trade across Canada, from formwork to finish stairs. Then drill one section at a time here, read every explanation, and finish with full timed mocks of 100 questions in four hours. Aim to score well above 70% in practice so a few hard questions on the day do not sink you.
Aptitude Tests Canada is an independent practice platform. We are not affiliated with or endorsed by Skilled Trades Ontario, the Red Seal Program or the Government of Ontario. Our questions are original practice questions, not real exam questions.
Three worked examples
One question from different sections of the full pack, with the answer and explanation.
A plank walkway on a project is used to move material by wheelbarrow. Fall protection is required if a worker on it may fall more than what height?
- 1.2 m
- 0.9 m
- 3 m
- 2.4 m
Using the 3-4-5 method in imperial, you mark 9 ft along one wall line and 12 ft along the other. What diagonal proves the corner is square?
- 18 ft
- 15 ft
- 13 ft
- 21 ft
You need 3.6 m3 of concrete. About how many cubic yards is that?
- 3.94 yd3
- 4.71 yd3
- 5.50 yd3
- 2.75 yd3