Durham Region
Second-storey additions in Durham Region
Second storey height limits across Durham Region, Ontario, with each town's share of pre-1981 homes and what a height variance or HST rebate involves.
Which Durham Region town gives a second storey the most height?
Pickering, in most of its detached zones: By-law 8149/24 allows 12.0 m in R1A to R1C and R1F to R1I, and Ajax allows 11.0 m across its R1 and R2 zones. Whitby's older R1 to R3 zones stop at 8.5 m and Oshawa's R1-A to R1-E zones at 9.0 m. Each town's zoning sets the limit, as of October 2026, and a taller roof needs that town's Committee of Adjustment.
Key takeaways
- Pickering's By-law 8149/24 allows 12.0 m in most of its detached zones, while By-law 1784 caps Whitby's older residential zones at 8.5 m (Pickering Zoning By-law 8149/24, Town of Whitby By-law 1784).
- About 37% of Durham Region's occupied homes were built before 1981, but the share is about 59% in Oshawa and about 23% in Ajax (Statistics Canada, 2021 Census).
- Ontario can now raise zoning maximums by regulation, but as of October 2026 only the setback percentage has been prescribed, so no Durham height limit has moved (Planning Act s. 34).
- A full second storey that at least doubles a bungalow's living space can count as owner-built housing, and Ontario's share of that rebate tops out at $24,000 (Canada Revenue Agency).
- The town's fee for a residential height variance is $856 in Oshawa but $2,760 in Scugog (City of Oshawa Committee of Adjustment, Township of Scugog 2026 planning fees).
Permits in Durham Region
What applies to second-storey additions here, with the municipal source for each line.
| Item | What applies | Source |
|---|---|---|
| Ajax: addition permit fee | $14.22 times the floor area; the Ajax schedule doesn't say whether the area is measured in m² or sq ft | ajax.caChecked 5 October 2026In the source's wordsSection A: CONSTRUCTION of new buildings, additions to existing buildings, including mezzanines |
| Brock: addition permit fee | $19.90 per m² | media-002-ca.cdn.govstack.comChecked 5 October 2026In the source's wordsNew or Additions - SFD, Semi Link, Towns $19.90 |
| Clarington: addition permit fee | $17.73 per m² | weblink.clarington.netChecked 5 October 2026In the source's wordsSingle Family Dwellings, Semis, Townhouses, Duplexes, Live/Work Units $17.73 per sq.m |
| Oshawa: addition permit fee | $15.56 per m² | media-002-ca.cdn.govstack.comChecked 5 October 2026In the source's wordsHouse, Accessory building for human habitation $15.56 / sq. m. |
| Pickering: addition permit fee | No separate addition line in the July 2026 fees; the Chief Building Official sets the building category and floor area (Building By-law 8057/23 s.15(3)). Residential buildings are $20.12 per m² of gross floor area | corporate.pickering.caChecked 6 October 2026In the source's wordsthe Chief Building Official, or a person designated by the Chief Building Official, shall determine the appropriate building category, floor area and/or value, and that determination shall be final. |
| Scugog: addition permit fee | $20.43 per m² | media-001-ca.cdn.govstack.comChecked 5 October 2026In the source's wordsNew Construction and Additions (for each m2 of GFA or part thereof) ... Other Residential Buildings $20.43 |
| Whitby: addition permit fee | $22.37 per m² | media-003-ca.cdn.govstack.comChecked 5 October 2026In the source's wordsResidential (SFD, Semi, Townhouse, Link, Duplex & Live/Work) - New / Additions Per m2 No $22.37 |
| Ajax: conservation authority (1) | Toronto and Region Conservation Authority (TRCA) | ajax.caChecked 5 October 2026In the source's wordsYour property might be in a regulated area; please reach out to Town Planning staff, the Toronto and Region Conservation Authority (TRCA), or the Central Lake Ontario Conservation Authority |
| Ajax: conservation authority (2) | Central Lake Ontario Conservation Authority (CLOCA) | cloca.comChecked 5 October 2026In the source's wordsSheet 1 - Lakeshore Ajax - Halls Road South, Whitby |
| Brock: conservation authority (1) | Lake Simcoe Region Conservation Authority (LSRCA) | lsrca.on.caChecked 5 October 2026In the source's wordsTownship of Brock - Memorandum of Understanding |
| Brock: conservation authority (2) | Kawartha Conservation | kawarthaconservation.comChecked 5 October 2026In the source's wordsOur municipal partners include: City of Kawartha Lakes, Township of Scugog, Township of Brock |
| Clarington: conservation authority (1) | Central Lake Ontario Conservation Authority (CLOCA) | cloca.comChecked 5 October 2026In the source's wordsOur municipal partners include the Region of Durham, Cities of Oshawa and Pickering, Towns of Ajax and Whitby, Municipality of Clarington and Townships of Scugog and Uxbridge. |
| Clarington: conservation authority (2) | Ganaraska Region Conservation Authority (GRCA) | grca.on.caChecked 5 October 2026In the source's wordsfrom Wilmot Creek in Clarington to east of Cobourg ... This area includes seven municipalities in whole or in part ... Municipality of Clarington |
| Clarington: conservation authority (3) | Kawartha Conservation | kawarthaconservation.comChecked 5 October 2026In the source's wordsOur municipal partners include: City of Kawartha Lakes, Township of Scugog, Township of Brock, Municipality of Clarington |
| Oshawa: conservation authority | Central Lake Ontario Conservation Authority (CLOCA) | oshawa.caChecked 5 October 2026In the source's wordscontact the Central Lake Ontario Conservation Authority (C.L.O.C.A.) |
| Pickering: conservation authority (1) | Toronto and Region Conservation Authority (TRCA) | pickering.caChecked 5 October 2026In the source's wordsToronto Region Conservation Authority |
| Pickering: conservation authority (2) | Central Lake Ontario Conservation Authority (CLOCA) | pickering.caChecked 5 October 2026In the source's wordsCentral Lakes Ontario Conservation Authority |
| Scugog: conservation authority (1) | Kawartha Conservation (most of Scugog) | scugog.caChecked 5 October 2026In the source's wordsThe Township of Scugog has three (3) Conservation Authorities, being Kawartha Conservation, Lake Simcoe Region Conservation Authority, and Central Lake Ontario Conservation Authority. |
| Scugog: conservation authority (2) | Lake Simcoe Region Conservation Authority (LSRCA) | lsrca.on.caChecked 5 October 2026In the source's wordsCouncillor Durham Region (Scugog) |
| Scugog: conservation authority (3) | Central Lake Ontario Conservation Authority (CLOCA) | cloca.comChecked 5 October 2026In the source's wordsOur municipal partners include ... Municipality of Clarington and Townships of Scugog and Uxbridge. |
| Whitby: conservation authority | Central Lake Ontario Conservation Authority (CLOCA) | whitby.caChecked 5 October 2026In the source's wordsCentral Lake Ontario Conservation Authority |
| Durham Region development charges, regional (as of 2026-07-01) | $76,227 | media-003-ca.cdn.govstack.comChecked 5 October 2026In the source's wordsTotal of All Charges $76,227 |
| Durham Region development charges, education (as of 2026-07-01) | $7,535 | media-002-ca.cdn.govstack.comChecked 5 October 2026In the source's wordsResidential (per dwelling unit) $4,349 $3,186 $7,535 |
Fees and rules as published by each municipality in Durham Region and the agencies linked, checked 6 October 2026. Confirm with the building department before you apply.
The nearest finished jobs
West Lynde
New second storey of about 800 sq ft with two bedrooms, a walk-in closet and a bathroom; new kitchen, two new bathrooms, floors, stairs and trim below.
Explore the home
Greenwood
Top floor replaced with a new storey, rear extension, basement enlarged, full interior design and build.
Explore the home
What it costs
Ranges with their sources, not quotes.
| 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 |
Our 2026 ranges, not quotes: every job is priced after a site visit.
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
Building in Durham Region
Where in Durham Region is a second storey easiest to fit?
Height and housing age pull in opposite directions across Durham: Oshawa, with the most older homes, stops at 9.0 m, while Ajax, with some of the newest, allows 11.0 m. The full picture, as of October 2026:
| Town | Max height, common detached zone | Homes built before 1981 (2021) | Single detached share of homes (2021) |
|---|---|---|---|
| Oshawa | 9.0 m (R1-A to R1-E) | about 59% | about 56% |
| Pickering | 9.0 m (R1D, R1E); 12.0 m (other R1 zones) | about 31% | about 60% |
| Clarington | 10.5 m (R1); Bowmanville overlay adds height-of-dwelling rules | about 27% | about 78% |
| Whitby | 8.5 m (R1 to R3, By-law 1784; 9.5 m for older houses; newer zones differ) | about 25% | about 70% |
| Ajax | 11.0 m (R1, R2) | about 23% | about 65% |
| Uxbridge | 10 m (R1) | about 42% | about 81% |
| Scugog | 10 m (urban residential) | about 53% | about 89% |
| Brock | 9 m (residential) | about 64% | about 87% |
| Durham Region | Set by each town | about 37% | about 66% |
Note: heights from each town's zoning by-law for its usual detached zone, and census shares are our arithmetic from Statistics Canada counts of occupied homes; StatCan's counts can't tell you which homes are one-storey or where they stand.
Oshawa holds most of the region's older stock: 15,700 of its homes date from 1960 or earlier, nearly half of Durham's 34,065. Brock and Scugog have higher shares, but they're small townships with far fewer homes. Whether 9.0 m is enough depends on your ceiling heights, the roof pitch and where the by-law measures from. If the design runs over, Oshawa's variance fee is the lowest we found in Durham at $856, though its page doesn't state the year.
Ajax's 11.0 m gives room for a full storey and a pitched roof on most lots, but only about 9,100 Ajax homes date from before 1981. In Whitby, the 8.5 m figure applies to the older R1 to R3 zones; By-law 1784 lets buildings that existed before By-law 3465-94 go to 9.5 m.
Height is only half of it. A second storey loads the existing walls and footings, so an engineer checks them before the design is final. West Lynde, our nearest finished second storey, is a bungalow in Whitby that we took to two storeys; Greenwood, in Toronto, is a top floor rebuilt on an older house.
How the job runs in Durham Region
Meet James
James meets you at the house, hears what you want and gives you a rough estimate on the spot. The first estimate is free.
Proposal and contract
If the estimate works for you, James prepares a detailed proposal. The whole project is priced, and the contract signed with a 10% deposit, before any design work begins.
Design onboarding
Our designer sends you an onboarding email with some homework: your style, how your family uses the house, and what you need and want. You share Pinterest boards, then go through them together on a Zoom call: what you like in the pictures, and what you don't.
Measure and floor plans
The designer measures the house and draws the floor plan: which walls come out, where the stairs land, how new space joins the old. We go through it with you until it's confirmed.
Drawings and 3D rendering
With the plan confirmed, she draws the elevations and the millwork, then puts it all into a 3D rendering, so you see the rooms before anyone orders a cabinet.
Finishes presentation
We don't take you round the stores: there are too many options. Using what she learned in onboarding, the designer narrows the tile, flooring, quartz, plumbing fixtures and the rest to a few choices that suit your style, collects the samples and presents them to you in our office. If a selection changes the price, the change goes through a change order you sign.
Permits and engineering
We prepare the permit drawings, bring in the structural engineer wherever a beam or a load changes, and apply to the municipality. If the plan changes after the permit is issued, we file the amendment. Each municipality in Durham Region takes its own applications; the table above names where.
Construction
Our crew and trades build it, with one point of contact from demolition to the last coat of paint. Our site supervisors write a job log every day, which you can follow in our online app. When we open a wall and find a problem, you hear about it, and what it costs, before we fix it.
Inspections
The municipal building inspector checks the work at each stage the permit sets, before it gets covered up. Inspections are booked with the local building department.
Handover
We walk the finished house with you and put right anything that isn't. On one job a stair stain didn't match the new floor, so we refinished the stairs.
Credentials
- Written warranty1 year workmanship and materials, 2 years plumbing, heating, electrical and building envelope, 7 years structural
- BBB Accredited BusinessAccredited by the Better Business Bureau since November 2025
- Durham Region Home Builders' AssociationMember, Renovators
- RenoMarkRenoMark renovator, through the DRHBA
Questions
Where in Durham Region are most homes built before 1981?
Does Ontario's as-of-right rule raise height limits in Durham Region?
Can a Durham Region second storey qualify for the HST new housing rebate?
What does a height variance cost across Durham Region?
How long did Jarvis's last bungalow-to-two-storey job take?
Sources
- City of Pickering, Zoning By-law 8149/24 corporate.pickering.ca
- Town of Ajax, Zoning By-law 95-2003 Section 6 ajax.ca
- Town of Whitby, Zoning By-law 1784 (2025 consolidation) media-003-ca.cdn.govstack.com
- City of Oshawa, Zoning By-law 60-94 media-002-ca.cdn.govstack.com
- Municipality of Clarington, Zoning By-law 84-63 media-003-ca.cdn.govstack.com
- Statistics Canada, 2021 Census Profile, Durham Region www12.statcan.gc.ca
- Statistics Canada, 2021 Census Profile, Uxbridge www12.statcan.gc.ca
- Statistics Canada, 2021 Census Profile, Scugog www12.statcan.gc.ca
- Statistics Canada, 2021 Census Profile, Brock www12.statcan.gc.ca
- Planning Act (Ontario) ontario.ca
- Canada Revenue Agency, GST/HST new housing rebate canada.ca
- Town of Ajax: Building By law 48 2023 Sch A Jan 01 2026 ajax.ca
- Township of Brock: Schedule a 2026 fees web media-002-ca.cdn.govstack.com
- Municipality of Clarington: ElectronicFile weblink.clarington.net
- City of Oshawa: Bylaw 33 2009 as amended by by law 118 2025 media-002-ca.cdn.govstack.com
- City of Pickering: DocView corporate.pickering.ca
- Township of Scugog: Required building fees 2026 media-001-ca.cdn.govstack.com
- Town of Whitby: 2026 building permit fees schedule n media-003-ca.cdn.govstack.com
- Town of Ajax: Committee of adjustment ajax.ca
- CLOCA: Regulation area mapping cloca.com
- LSRCA: Governance lsrca.on.ca
- Kawartha Conservation: About us kawarthaconservation.com
- CLOCA: About us cloca.com
- grca.on.ca grca.on.ca
- City of Oshawa: Building permits oshawa.ca
- City of Pickering: Building permits pickering.ca
- Township of Scugog: Additional dwelling units scugog.ca
- Town of Whitby: Building permits whitby.ca
- Durham Region: Durham region wide development charge information jul 1 2026 media-003-ca.cdn.govstack.com
- City of Pickering: Developmentcharges citywide 2026 media-002-ca.cdn.govstack.com
How this page was made
Written by Jarvis Contracting from the municipalities' published rules, our 2026 price ranges and the nearest finished jobs.
- Facts checked
- 6 October 2026
- Fact-checked
- Space & Story, 5 October 2026