# Must an owner list asbestos before a commercial renovation?

> Ontario's Occupational Health and Safety Act: a project owner lists designated substances such as asbestos, lead and silica before a commercial contract.

- Canonical HTML: https://www.jdtconstruction.ca/guides/designated-substances/
- Section: Home > Guides > Asbestos and designated substances
- Business: JDT Construction Inc., Hamilton, ON, Canada (serves Hamilton)
- Phone: (905) 818-0106 | Email: johnny@jdtconstruction.ca
- Page updated: 2026-11-05

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Guides

Yes. Ontario's Occupational Health and Safety Act requires a project owner to find out whether designated substances, such as asbestos, lead, mercury or silica, are on the site before the project begins, list them, and give the list to the constructor before signing the contract. An owner who skips it can be liable for the losses. JDT Construction asks for that list on commercial jobs in Hamilton.

## What does the law say?

Section 30: “Before beginning a project, the owner shall determine whether any designated substances are present at the project site and shall prepare a list of all designated substances that are present at the site.” [(Occupational Health and Safety Act, s. 30 (1), read November 5, 2026)](https://www.ontario.ca/laws/statute/90o01)

**The designated substances duty on an Ontario project, from section 30 of the Occupational Health and Safety Act**

| Who | Must |
| --- | --- |
| The owner | Determine whether designated substances are present and list them before the project begins (s. 30 (1)) |
| Whoever issues tenders | Include the list in the tendering information (s. 30 (2)) |
| The owner | Make sure a prospective constructor has the list before a binding contract (s. 30 (3)) |
| The constructor | Make sure each prospective contractor and subcontractor has it before their contracts (s. 30 (4)) |
| An owner who does not comply | Is liable for losses from a substance later found that the owner ought reasonably to have known of (s. 30 (5)) |

## Which substances are designated?

Eleven, named in Ontario Regulation 490/09: acrylonitrile, arsenic, asbestos, benzene, coke oven emissions, ethylene oxide, isocyanates, lead, mercury, silica and vinyl chloride [(O. Reg. 490/09, read November 5, 2026)](https://www.ontario.ca/laws/regulation/090490). In an older commercial building the usual ones are asbestos in tiles, plaster, insulation or drywall compound, lead in paint, mercury in lamps and switches, and silica in concrete and masonry.

## How is the list made?

Usually by a designated substances survey: a consultant inspects and samples the areas the work will touch and writes a report. That report becomes the list the Act requires. Asbestos removal itself has its own notices before work ([Notice of Project and the constructor](https://www.jdtconstruction.ca/guides/notice-of-project/)).

## Does this apply to a house?

This page is about commercial and other workplace projects, where the duty is plain. Whether and how it applies to a private home is a question for the Ministry of Labour or a lawyer, so this page does not answer it. A house built before the 1990s can still contain asbestos, and tearing one down has its own rules ([tearing down a house to rebuild](https://www.jdtconstruction.ca/guides/demolition/)).

## How does JDT handle it?

On a commercial job JDT Construction Inc. asks for the owner's list before the proposal is signed, and the work is planned around it. The other approvals for a commercial build are on the [commercial page](https://www.jdtconstruction.ca/builds/commercial/).

Published by JDT Construction Inc., Hamilton. Updated November 5, 2026. Free to share and quote, with a link back to this page.

## Renovating a commercial space?

Send the address and what the space needs. Have the designated substances report ready if there is one.

[Call (905) 818-0106](tel:+19058180106) [Request a quote](https://www.jdtconstruction.ca/request/?problem=commercial)

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JDT Construction Inc. Call (905) 818-0106. Full site: https://www.jdtconstruction.ca/