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Learn/Building Code Act, 1992/s.1–1.1

Interpretation, definitions and roles

Building Code Act, 1992 · s.1–1.1Designer legal/processAbout 15 min

What counts as a building, what counts as construction, and who is responsible for what.

Study notes, not an official interpretation. About these notes

Only the Minister’s binding interpretations (Act s.28.1) and the decisions of the chief building official on a real project are authoritative.

Quoted from the Building Code Act, 1992, S.O. 1992, c. 23, as consolidated on e-Laws (current from June 2, 2026). Provisions not yet in force are not shown. This copy is for study; the official version is on e-Laws.

Each provision is quoted word for word. Study summaries, background, examples, exam traps and recall answers are ours: shorthand for memory and made-up scenarios for study, not a substitute for the text. On a real project, the chief building official decides how the Act applies.

Confirm against the official text of the Act and the Code before relying on anything.

1Recall before you read

Take a guess first. Being wrong is fine.

A guess, even a wrong one, primes you to notice the answer when you meet it. Your guesses are saved; the answers come in step 6, right after the provisions and the diagram.

A 9 m² garden shed with no plumbing. Is it a “building” under the Act?

Whose role is it to make sure construction doesn’t start without a permit?

2Section map

The skeleton: what lives where

s.1(1)

Definitions

Building, construct, demolish, plumbing, principal authority and more.

s.1(1.1)–(1.3)

Reading the Act

What “this Act” and “chief building official” include.

s.1(2)

Exclusion

Structures used directly in extracting ore from a mine.

s.1.1(1)

Person causing construction

Build to the Act, Code and permit; no work without a permit.

s.1.1(2)

Designer

Compliant, detailed designs, only within qualifications.

s.1.1(3)

Builder

Permit first, build to the permit, flag site conditions.

s.1.1(4)–(5)

Products, owners, evaluators, RCAs

Manufacturers, building owners, evaluators and registered code agencies.

s.1.1(6)–(8)

CBO and inspectors

Independent enforcement; roles don’t relieve anyone of duties.

3Background · study notes

Why these provisions matter

The Act regulates a narrow set of activities, so the definitions decide whether it applies at all. A structure that isn’t a “building”, or work that isn’t “construction”, needs no permit under the Act.

Section 1.1 then spreads responsibility across everyone involved: owner, designer, builder, supplier, agency, official and inspector. It describes roles rather than creating new offences, and s.1.1(8) makes clear that none of these roles relieves anyone of the duty to comply with the Act or the Code.

Clarity of scopeShared responsibility

4The provisions

What the Act says, and where

“Building”s.1(1) “building”

What the Act says, word for word

s.1(1) “building”
“building” means,
(a) a structure occupying an area greater than ten square metres consisting of a wall, roof and floor or any of them or a structural system serving the function thereof including all plumbing, works, fixtures and service systems appurtenant thereto,
(b) a structure occupying an area of ten square metres or less that contains plumbing, including the plumbing appurtenant thereto,
(c) plumbing not located in a structure,
(c.1) a sewage system, or
(d) structures designated in the building code; (“bâtiment”)

Study summary: Five ways something is a building: a structure over 10 m², a smaller structure with plumbing, plumbing outside a structure, a sewage system, or a structure the Code designates.

Watch for: Clause (a) says “greater than ten square metres”.

“Construct”s.1(1) “construct”

What the Act says, word for word

s.1(1) “construct”
“construct” means to do anything in the erection, installation, extension or material alteration or repair of a building and includes the installation of a building unit fabricated or moved from elsewhere and “construction” has a corresponding meaning;

Study summary: Covers erecting, installing, extending, materially altering or repairing, including installing a unit built or moved from elsewhere.

“Demolish”s.1(1) “demolish”

What the Act says, word for word

s.1(1) “demolish”
“demolish” means to do anything in the removal of a building or any material part thereof and “demolition” has a corresponding meaning;

Study summary: Removing a building or any material part of it.

“Municipality”s.1(1) “municipality”

What the Act says, word for word

s.1(1) “municipality”
“municipality” means a local municipality;

Study summary: A local municipality.

Watch for: Upper-tier roles come through the agreements in s.3, 6.1 and 6.2.

Miness.1(2)

What the Act says, word for word

s.1(2)
This Act does not apply to structures used directly in the extraction of ore from a mine.

Study summary: The Act doesn’t apply to structures used directly in extracting ore.

Who “chief building official” includess.1(1.3)

What the Act says, word for word

s.1(1.3)
A reference to the “chief building official” in this Act, other than in subsections 1 (1), 3 (2), (3) and (6) and section 4, includes an inspector who has the same powers and duties as the chief building official,
(a) in relation to sewage systems by virtue of subsections 3.1 (3) or 6.2 (4); and
(b) in relation to plumbing by virtue of subsection 6.1 (5).

Study summary: In most of the Act, an inspector with CBO powers for sewage systems or plumbing is included.

Person causing constructions.1.1(1)

What the Act says, word for word

s.1.1(1)
It is the role of every person who causes a building to be constructed,
(a) to cause the building to be constructed in accordance with this Act and the building code and with any permit issued under this Act for the building;
(b) to ensure that construction does not proceed unless any permit required under this Act has been issued by the chief building official; and
(c) to ensure that construction is carried out only by persons with the qualifications and insurance, if any, required by this Act and the building code.

Study summary: Build to the Act, Code and permit; no work without a permit; use qualified, insured people.

Designers.1.1(2)

What the Act says, word for word

s.1.1(2)
It is the role of a designer,
(a) if the designer’s designs are to be submitted in support of an application for a permit under this Act, to provide designs which are in accordance with this Act and the building code and to provide documentation that is sufficiently detailed to permit the design to be assessed for compliance with this Act and the building code and to allow a builder to carry out the work in accordance with the design, this Act and the building code;
(b) to perform the role described in clause (a) in respect of only those matters for which the designer has the qualifications, if any, required by this Act and the building code; and
(c) if the building code requires that all or part of the design or construction of a building be under general review, to perform the general review in respect of only those matters for which the designer has the qualifications, if any, required by this Act and the building code.

Study summary: Designs that comply and are detailed enough to assess and build from, within the designer’s qualifications.

Builders.1.1(3)

What the Act says, word for word

s.1.1(3)
It is the role of a builder,
(a) to ensure that construction does not proceed unless any permit required under this Act has been issued by the chief building official;
(b) to construct the building in accordance with the permit;
(c) to use appropriate building techniques to achieve compliance with this Act and the building code; and
(d) when site conditions affect compliance with the building code, to notify the designer and an inspector or the registered code agency, as appropriate.

Study summary: Permit first, build to it, use good technique, and flag site conditions that affect compliance.

Roles don’t excuses.1.1(8)

What the Act says, word for word

s.1.1(8)
Nothing in this section relieves any person from the duty to comply with any part of this Act or the building code or affects the rights or duties of a person not mentioned in this section in respect of the construction of a building.

Study summary: Section 1.1 doesn’t reduce anyone’s duty to comply.

5See it

Is it a “building” under the Act?

Work down the definition in s.1(1) in order. The first “yes” brings it within the definition.

6Recall answers · study notes

How did your guesses do?

The answers to the questions you guessed at in step 1, with the provision each one comes from. If a guess was off, reread that provision above before the check.

1A 9 m² garden shed with no plumbing. Is it a “building” under the Act?

Your guess: No guess entered

Answer

On the wording of s.1(1), clauses (a) and (b) don’t catch it: it isn’t over 10 m² and has no plumbing. Clause (d) would apply only if the Code designates that kind of structure. On a real project, confirm with the chief building official.

2Whose role is it to make sure construction doesn’t start without a permit?

Your guess: No guess entered

Answer

Both the person who causes the building to be constructed (s.1.1(1)(b)) and the builder (s.1.1(3)(a)).

7In the field · illustrative

Worked example: A prefabricated cabin arrives on a trailer

A homeowner buys a 14 m² prefabricated cabin, built in a factory, and has it set on piers at the back of the lot. Nothing is built on site.

Is it a building?Yes. It is over 10 m², so clause (a) of “building” applies. s.1(1)

Is setting it on the lot “construction”?Yes. “Construct” includes installing a building unit fabricated or moved from elsewhere. s.1(1)

Who must make sure there’s a permit?The homeowner, as the person causing construction, and whoever installs it as builder. s.1.1(1)(b), (3)(a)

8Exam traps · study notes

Where people lose marks

Reading tips for exam questions, each tied to a provision above.

The 10 m² line. Clause (a) needs an area greater than 10 m². Exactly 10 m² with no plumbing is not caught by (a) or (b).
“It was built somewhere else.” Installing a unit fabricated or moved from elsewhere is still construction.
Roles aren’t a shield. s.1.1(8): describing someone’s role never reduces their duty to comply.
“Chief building official” can mean more than one person. s.1(1.3): it includes an inspector with CBO powers for sewage systems or plumbing.

9Check yourself

Three questions, book closed

Close your notes and pull the answers from memory. Testing yourself strengthens a memory far more than rereading it. Each check draws 3 of this lesson’s 6 questions, favouring ones you haven’t got right yet, so a retake is a different check. Each question asks how sure you are, and your answers set your review schedule.

Start the 3-question check

10Find it yourself · open book

Now find it in the real text

The exam is open book, so finding a provision fast is a skill of its own. Open Building Code Act, 1992 on e-Laws in another tab, use its table of contents to find each provision below, and type the section number you land on. Aim for under a minute each.

Open the official text on e-Laws

1

“Building”

In the Building Code Act: Five ways something is a building: a structure over 10 m², a smaller structure with plumbing, plumbing outside a structure, a sewage system, or a structure the Code designates.

2

“Demolish”

In the Building Code Act: Removing a building or any material part of it.

3

Mines

In the Building Code Act: The Act doesn’t apply to structures used directly in extracting ore.

4

Designer

In the Building Code Act: Designs that comply and are detailed enough to assess and build from, within the designer’s qualifications.

5

Roles don’t excuse

In the Building Code Act: Section 1.1 doesn’t reduce anyone’s duty to comply.

Clues are our study summaries, not the wording of the provision. Try the check first; this step works best after it.