Renovate Now or Build Next Spring? What Ontario Permit Timelines Actually Look Like
Every year around this time, we have some version of the same conversation.
A homeowner calls in August. They've been thinking about a second-storey addition, or a whole main-floor rebuild, since about February… Right before, the kids are back in school, they've finally decided.
And the question is always the same: can we get this done before winter?
The honest answer is usually no, and that's not the bad news it sounds like. Because the follow-up question is the one that actually matters: what do we need to do now so we can break ground in spring?
The gap between those two questions is oftentimes the permit process.
Here's what it actually looks like.
The 10-business-day rule, and why it misleads everyone
The Ontario Building Code sets statutory review windows. Once your application is deemed complete, the municipality has to issue or refuse it (with written reasons) within 10 business days for a house, 15 for a small building, 20 for a large one, and 30 for something complex.
Ten business days. Two weeks. Sounds fast.
The catch is in these words: deemed complete. That clock does not start when you submit. It starts when the building department agrees your submission is complete. That means drawings, structural details, zoning compliance, applicable law clearances, the whole package. An incomplete application doesn't fail; it just sits, and the clock never begins.
This is why online answers range from "two weeks" to "six months" and both are technically true. The variable isn't the municipality. It's the quality of what you handed them.
The real sequence for a major renovation or addition
Here's a realistic timeline for the kind of work we do, second-storey additions, whole-home renovations, custom builds, in Oakville, Burlington and Hamilton.
Design and drawings: 6–12 weeks. This is the part homeowners consistently underestimate. Permit-ready drawings aren't concept sketches. They're a coordinated set showing structure, framing, foundation details, insulation and vapour barrier assemblies, mechanical, egress, and everything the examiner needs to confirm code compliance. If a structural engineer is involved, and on any second storey or load-bearing removal, one is, that coordination happens during design, not after the first examiner's notice.
Zoning check: do this first, not last. Before drawings get far, someone needs to confirm what you're allowed to build. Setbacks, lot coverage, height, floor area ratio. If the design fits as-of-right, you go straight to permit. If it doesn't, you're in a different process entirely.
Minor variance (only if needed): 2–4 months. If your design needs relief from the zoning bylaw, you're applying to the Committee of Adjustment. Circulation and notice take weeks before a hearing is even scheduled. After a decision, there's a 20-day appeal period to the Ontario Land Tribunal — and the decision isn't final until that window closes. This is the single biggest schedule variable in a major renovation, and it's entirely predictable if the zoning review happens early.
Permit review: 10 business days, plus revision cycles. The statutory clock, plus whatever back-and-forth the examiner's comments generate. Most first submissions get comments. Each resubmission restarts a review cycle. A clean, well-coordinated residential file typically lands in the 6–12 week range from first submission to permit in hand.
Add it up. For a straightforward addition with no variance: roughly 3–5 months from first design meeting to permit. For a custom home or a project needing a variance: 6–9 months is a realistic planning assumption.
So what does August actually mean?
Start now, break ground in spring. This is the honest answer for most major projects, and it's a good outcome. Design through fall, permit through winter, mobilize in April with a full construction season ahead of you. Winter is also when building departments see lower application volume, which doesn't shorten the statutory clock but often shortens the queue.
Start in spring, break ground in fall. This is what happens when the process starts in March. You spend the best building months of the year in design and review, then start construction heading into the worst weather. It works. It's just a worse version of the same year.
Smaller scoped work can still happen this year. Interior renovations that don't require structural change move faster. Anything involving foundation, framing, or envelope is a different conversation in October than it is in April.
The part that isn't about the calendar
Permit timelines largely stall when drawings are incomplete, because the structural engineer got involved too late, because nobody checked zoning until the design was already emotionally locked in, because the mechanical layout contradicts the framing plan.
That's the argument for keeping design and construction under one roof rather than in two separate contracts. When the people drawing it are accountable for building it, the submission tends to arrive complete and a complete submission is the only kind the statutory clock applies to. We handle drawings, permit submission, and the municipal back-and-forth as part of the project.
What to do in the next few weeks
If you're thinking about a 2027 build or a major renovation:
Get a zoning read on your property. It costs nothing and it determines everything.
Have a real conversation about scope and budget before drawings start.
Assume the permit process will take longer than the number you have in your head.
Decide now, so that fall is design and winter is review.
The homeowners breaking ground next April are the ones having this conversation in August.
Book a consultation with Onelife Design & Build. We'll walk through your property, your scope, and a realistic timeline for getting it permitted and built across the Halton region.
