Do You Need a Permit to Build a Deck in Kingston, Brockville or Gananoque?
Last updated: October 21, 2026
In all three towns, a deck higher than about 600 mm (2 ft) above the ground needs a building permit, and the other tests differ. Kingston and Gananoque also list a size test of 10 square metres (about 108 sq ft). Brockville's 2026 notice adds three more: a deck attached to the house, one that serves an exit door, and one that supports a roof, enclosure or privacy wall. Zoning applies even when no permit is needed. Below is each town's rule, fee and application route from its own pages.
When does a deck need a building permit?
| Kingston | Brockville | Gananoque | |
|---|---|---|---|
| Permit needed | Higher than 600 mm above ground (deck permit page). Its general permits page also lists a deck larger than 10 m² (108 sq ft) or two feet above the ground. | Any one of: attached to a house; surface more than 600 mm (24 in) above finished grade; covers more than 108 sq ft; serves the principal entrance or an exit door; supports a roof, enclosure or privacy wall. | A deck larger than 10 m², or two feet above the finished grade. |
| Listed as no permit | A roofless deck under two feet above the adjacent grade that complies with zoning. | Not listed as an exemption. A deck that meets none of the five tests is not named as needing one. | A roofless deck under two feet above the adjacent grade that is not attached to a building, subject to zoning. |
| Review time | Within 10 business days of a complete application | 10 business days for a complete residential deck application (Ontario Building Code) | Not stated on the page we read |
| 2026 permit fee | $252.05 per deck (Building Services fee summary, effective January 1, 2026) | The greater of $238.00 or $0.51 per sq ft of deck area | Not published on the pages we read. Ask the Building Department. |
| Apply | DASH portal | Cloudpermit | Cloudpermit |
| Contact | buildingpermits@cityofkingston.ca, (613) 546-4291 ext. 3280 | City of Brockville Building Services | (613) 382-2149 ext. 1132, cbo@gananoque.ca |
Why do some of these pages seem to disagree?
They do, in two places, and you should know before you rely on a number:
- Kingston. The deck permit page states one test, 600 mm above ground. The general building permits page lists two, a size of more than 10 m² or a height of two feet. We read both as current. If your deck is low but large, ask Building Services which applies.
- Brockville. The City's spring deck reminder, posted June 9, 2026, lists the five tests in the table. An older City notice from May 2023 gives a simpler 10 m² or 0.61 m test. We used the 2026 notice. The attached-to-the-house rule appears only there, so assume it applies.
Does zoning still apply if you do not need a permit?
Yes, in all three. Kingston says a no-permit deck must still comply with its zoning by-law, and its deck page carries a table of setbacks by deck height. Brockville says zoning applies even where no permit is required, and that decks count toward lot coverage. Gananoque says zoning by-laws still apply and your project may need planning approval. A deck that breaks zoning rules may need a redesign or a minor variance, so check before you order lumber.
What happens during construction in Kingston?
Kingston says building a deck before getting the permit is an offence. Once you have it, there are three inspections: the excavated post holes before concrete goes in, the framing before the top boards and guards go on, and a final inspection of the finished deck. Book each at least 24 hours ahead. The inspector's name and number are on the permit.
How much does a deck permit cost?
Kingston charges $252.05 per deck in 2026. Brockville charges the greater of $238.00 or $0.51 per square foot, so a 300 sq ft deck would be $238.00 and a 600 sq ft deck $306.00. Gananoque's fee is not on the pages we read, so ask. We do not publish what a deck costs to build, because we could not source reliable local prices. Get written quotes.
Who builds decks near you?
Businesses in our directory that list deck work:
- Gananoque: Deck Medics is listed under decks.
- Brockville: Heffernan Homes Construction and Madawaska Exteriors list decks among their services.
- Kingston: we do not currently tag a Kingston business as a deck builder. Several fence companies on our Kingston fencing page have decks in their names, so check their listings or websites for deck work.
Ask any builder who applies for the permit, who books the three inspections, and whether the quote includes both. A listing is not a recommendation, and we have not ranked anyone.
Frequently asked questions
Do I need a permit to build a deck in Kingston?
Kingston's deck permit page says you need one if the deck is higher than 600 mm above ground. Its building permits page also lists a deck larger than 10 square metres or two feet above the ground. A roofless deck under two feet above the adjacent grade that complies with zoning is listed as not needing one.
Do I need a permit to build a deck in Brockville?
Brockville's June 2026 notice says yes if the deck is attached to a house, more than 600 mm above finished grade, over 108 square feet, serves an exit door, or supports a roof, enclosure or privacy wall.
Do I need a permit to build a deck in Gananoque?
Yes for a deck larger than 10 square metres or two feet above the finished grade. A roofless deck under two feet above the adjacent grade that is not attached to a building is listed as not needing one, subject to zoning.
How much is a deck permit in Kingston and Brockville?
Kingston charges $252.05 per deck in 2026. Brockville charges the greater of $238.00 or $0.51 per square foot of deck area.
How long does a deck permit take?
Kingston and Brockville both say a complete application is reviewed within 10 business days. Construction cannot start until the permit is issued.
Do zoning rules apply if I do not need a permit?
Yes. All three municipalities say zoning still applies to a deck that needs no permit.