Add space without moving.
A second storey, a rear extension or a side addition all add new square footage to a house that already exists, and all three always need a building permit. We prepare the full drawing package: site plan, existing and proposed floor plans, elevations, structural coordination, and everything your municipality’s zoning bylaw checks before it issues a permit.
Zoning checks it first. So do we.
- Rear yard11 m left behind the addition, against a typical 7.5 m.Fits
- HeightOne storey, matched to the existing house. Well under the cap.Unchanged
- Lot coverageBuildings cover 36% of the lot. Assumed cap 35%.Variance
- Committee of AdjustmentA minor variance: a public hearing before the permit, and more time on the schedule.Variance
Typical figures, not your bylaw. Your zone sets the real setback, height and coverage numbers, and we check them before drawings start.
Every addition is one of these three.
Second storey
A new floor built on top of the existing footprint.
- What usually drives cost
- Structural upgrades to carry the new load, and a roof rebuild.
Rear addition
New footprint extending into the backyard.
- What usually drives cost
- Foundation work, and the rear-yard setback.
Side addition
New footprint extending to one side.
- What usually drives cost
- The side-yard setback, and the condition of the existing wall.
All three trigger a full building permit, not a minor-works exemption.
What zoning checks before structure does.
Before a drawing package can even go to structural review, it has to pass your municipality’s zoning bylaw. Three numbers decide most additions.
- 01
Setbacks
How far the new walls must sit from the property line. Set by your specific zone, not a single provincial rule.
Typical figureSide yard around 1.2 m for a two-storey portion
- 02
Height
The cap on building height, plus separate rules for how close to the property line you can build at that height.
Typical figure10–12 m in most low-density zones
- 03
Lot coverage
The maximum percentage of your lot that any building, the addition included, can occupy.
Typical figureSet per zone
Structural: coordinated, not ours.
A second storey or a rear addition tied into the existing structure almost always needs stamped structural calculations, which by law come from an outside licensed professional. We coordinate that as part of the drawing package, so it’s one submission, not two separate consultants for you to manage.
Site plan
The lot, the setbacks and where the addition sits.
Existing and proposed plans
Floor plans, elevations and sections, before and after.
Structural coordination
Stamped calculations from an outside licensed professional, folded in.
Timeline and fees, honestly.
~$3,000+ in Hamilton
A common base fee for a major alteration or addition, scaling with square footage on larger projects. Every municipality sets its own schedule.
Several weeks
Typical for a straightforward addition with a complete application.
Considerably longer
A Committee of Adjustment variance adds a public hearing before the permit.
Planning figures, not quotes. Your actual timeline and fee depend on your zone, your lot, and whether a variance is needed. Check the exact fee with the building department before budgeting.
Pick the question closest to yours.
Basic vs. Major Renovation
What separates a cosmetic renovation from one that needs a building permit.
Do I Need a Permit?
A self-check before you call anyone.
Process
Feasibility check, drawings, coordination and permit submission, in order.
What your zoning allows, before you spend on drawings.
Tell us the addition you’re picturing, and we’ll check it against your zone first.