Jarvis / Design & build
What additions and renovations cost in 2026
Our 2026 ranges for each kind of work we do, with what moves the number. They're ranges, not your quote: we price your job after a site visit, and the first estimate is free.
How we price a job
We don't price from a chart. James sees the house and gives you a rough estimate on the spot, then a detailed proposal: the whole project is priced, and the contract signed, before any design work begins. Our contracts are fixed price. If a design selection or finish changes the price, the change goes through a change order you sign. Our guide to fixed price and cost-plus explains the two ways contractors charge.
What the ranges leave out
Unless a row says otherwise, every range here is before 13% HST. Our drawing prices are the drawings alone: permit fees, HVAC engineering, truss design, a committee of adjustment application and anything unforeseen are extra. Whoever you ask, check what their number includes.
What Ontario law says about estimates
A renovation over $50 needs a written contract, and the final price can't exceed the estimate by more than 10% unless you agree to changes (ontario.ca).
Budgeting for your home
Home additions
| Work | Range | Basis | Source |
|---|---|---|---|
| Home addition, any type | $350 to $600per sq ft | GTA, 2026. Before 13% HST. | Our 2026 price |
| Single-storey rear addition, 300 to 700 sq ft | $180,000 to $450,000 | GTA, 2026. Before 13% HST. | Our 2026 price |
| Bump-out, 100 to 300 sq ft | $60,000 to $180,000 | GTA, 2026. Before 13% HST. | Our 2026 price |
What moves the number
- The foundation: full basement, crawlspace or slab
- How much of the existing house opens up to join the new space
- The roof: new rafters meeting the old roof
- Engineering, drawings and the permit
- Finish level inside
- 13% HST, which these ranges leave out
Budgeting for your home
Second-storey additions
| Work | Range | Basis | Source |
|---|---|---|---|
| Second-storey addition, 600 to 1,200 sq ft | $300,000 to $800,000 | GTA, 2026. The new floor; a kitchen or bathrooms below add to it. Before 13% HST. | Our 2026 price |
What moves the number
- Whether the foundation and walls can carry the new floor, or need reinforcing
- A full storey or a partial one
- Whether the main floor is redone at the same time
- The roof design and how it meets what's left
- Engineering, drawings and the permit
- Finish level, and 13% HST on top
Budgeting for your home
Basement renovations
| Work | Range | Basis | Source |
|---|---|---|---|
| Full legal basement apartment | $80,000 to $180,000 | 2026. Before 13% HST. | Our 2026 price |
| Basement bathroom | $25,000 to $50,000 | 2026; the top end when new plumbing goes under the slab. Before 13% HST. | Our 2026 price |
| Basement finishing | $55 to $90per sq ft | 2026, by finish level. Before 13% HST. | Our 2026 price |
| Legalising an already-finished basement | $45,000 to $95,000 | 2026. Before 13% HST. | Our 2026 price |
| Separate side-door entrance | $18,000 to $28,000 | 2026. Before 13% HST. | Our 2026 price |
| Underpinning the full perimeter | $60,000 to $120,000 | 2026, when the ceiling is too low. Before 13% HST. | Our 2026 price |
What moves the number
- Ceiling height, and whether the floor has to be lowered or underpinned
- A second unit or not: fire separation, a second exit, a kitchen
- A separate entrance or a walkout
- Bathrooms and how far the plumbing runs
- Moisture or water damage found when the walls open
- Finish level, and 13% HST on top
Budgeting for your home
Whole-home renovations
No single range: every job is priced after a site visit.
What moves the number
- How much of the house changes
- Load-bearing walls, and the beams that replace them
- What's behind the walls: asbestos, knob-and-tube wiring, water damage
- Hiding pipes and ducts without bulkheads
- Finish level, and 13% HST on top
Budgeting for your home
Kitchen renovations
| Work | Range | Basis | Source |
|---|---|---|---|
| Kitchen renovation, mid-range | $40,000 to $75,000 | 2026. Before 13% HST. | Our 2026 price |
| Kitchen renovation, premium | $85,000 to $150,000 | 2026. Before 13% HST. | Our 2026 price |
What moves the number
- Moving the sink, the range or a wall
- Cabinets: stock, semi-custom or custom
- Counters and stone
- Appliances
- Structural work when walls come out
- 13% HST on top
Budgeting for your home
Bathroom renovations
| Work | Range | Basis | Source |
|---|---|---|---|
| Basement bathroom | $25,000 to $50,000 | 2026; the top end when new plumbing goes under the slab. Before 13% HST. | Our 2026 price |
What moves the number
- Moving the toilet, shower or drain
- Tile: size, pattern and how much of the room it covers
- Vanity, glass and fixtures
- Water damage under the old floor
- 13% HST on top
Budgeting for your home
Architectural design and permit drawings
| Work | Range | Basis | Source |
|---|---|---|---|
| Permit drawings for an addition | $6,000 to $12,000 | 2026. Drawings only: permit fees, HVAC engineering, truss design, committee of adjustment applications and anything unforeseen are extra. Before 13% HST. | Our 2026 price |
| Permit drawings for a basement apartment | $4,000 to $8,000 | 2026. Drawings only: permit fees, HVAC engineering, truss design, committee of adjustment applications and anything unforeseen are extra. Before 13% HST. | Our 2026 price |
| Permit drawings for a garden suite | $5,000 to $15,000 | 2026. Drawings only: permit fees, HVAC engineering, truss design, committee of adjustment applications and anything unforeseen are extra. Before 13% HST. | Our 2026 price |
What moves the number
- Size and complexity
- Structural engineering
- A minor variance application
- How many design revisions
Budgeting for your home
Design-build
No single range: every job is priced after a site visit.
What moves the number
- The scope you choose
- The finishes you pick with the designer
- Structural work
- 13% HST on top
Where there's no range
Whole-home renovations and design-build projects vary too much for one range, so we don't print one. They're priced after James sees the house. The service pages list what drives each one.
Sources
- ontario.ca ontario.ca