Home/Modular Homes by City/Ottawa
Serving Ottawa & the National Capital Region
Modular Homes & Garden Suites in Ottawa, Ontario
Factory-direct modular homes and backyard suites for Ottawa. Ottawa calls a detached backyard unit a “coach house” — here's what's allowed on your lot, what it costs, and the rules that apply. (Ottawa is mid-transition between two zoning by-laws, so the more restrictive provisions apply.)
What you can build in Ottawa
Full modular homes — from $175,696. 29 models from 560 to 1,405 sq ft, 1–3 bedrooms — factory-built to the Ontario Building Code and set on a permanent foundation (a real, permanent house, not a “trailer”).
Backyard suites (ADUs) — from $96,244. 7 compact models built for garden-suite and in-law-suite use, sized to fit what Ottawa's by-law allows.
All homes are CSA-certified (A277 modular / Z240MH manufactured), finished in the factory, and delivered ready for foundation and hook-up. What's the difference between modular, manufactured, and mobile? →
Find your backyard suite — 3 quick questions
We'll narrow the models that fit a typical Ottawa backyard allowance to the ones that fit your life. No email needed.
1 · Who's it for?
2 · What layout?
3 · What size feels right? (Ottawa lots typically allow up to ~750 sq ft)
An Ottawa coach house is often limited by your home’s footprint (40%), not just the 80 m² cap — check your exact lot. Your exact lot may allow more or less — get the real number for your address in seconds.
Check your exact Ottawa address →Can you put a garden suite (ADU) in your Ottawa backyard?
Often, yes — Ottawa permits a detached Additional Residential Unit on most serviced residential lots. The specifics, from Ottawa Zoning By-law 2008-250 §133, plus the new By-law 2026-50 §701 — the most-restrictive provisions of both apply during the transition:
| Max size | 80 m² (≈860 sq ft) in urban/suburban Ottawa, 95 m² (≈1,025 sq ft) in rural zones — but the binding limit is usually the lesser of that, 40% of your home’s footprint, or 40% of the rear yard. |
|---|---|
| Max height | 3.6 m (≈12 ft) in most urban zones (3.2 m / ≈10.5 ft for a flat roof); 4.5 m (≈15 ft) in rural and village zones |
| Setbacks | Rear and side yards follow the underlying zone; a minimum 1.2 m (≈4 ft) separation from the main house |
| Parking | None required |
| Servicing | Municipal services in the urban area; private well/septic permitted in rural zones with approval |
| Conservation | Rideau Valley, Mississippi Valley, or South Nation Conservation Authority — depending on your watershed |
Getting your building permit in Ottawa
An eligible lot still needs a building permit before anything is delivered. Here's how Ottawa's process actually works — verified against the Ottawa building department's own pages.
How do you apply for an ADU building permit in Ottawa?
Through My ServiceOttawa (Building, Planning and Land Development portal) (application portal ↗). Applications are submitted digitally through a My ServiceOttawa account — upload plans, pay online, and book inspections in the same portal; in-person submission at a Client Service Centre remains an option, and a free pre-application consultation is available through 3-1-1. Ottawa's building-permit page ↗
- Take the free pre-application consultation with Building Code Services (call 3-1-1) to confirm zoning, servicing, and drawing requirements before you design
- If the coach house doesn't meet the Zoning By-law as-of-right, apply to the Committee of Adjustment for a minor variance first — a separate application, fee, and timeline
- Create a My ServiceOttawa account registered for the Building, Planning and Land Development service
- Prepare and submit the digital application package (application form, Schedule 1, site plan, floor plans, foundation plan, cross-sections)
- The City reviews the complete application (the legislated clock only runs once it's deemed complete)
- Pay the permit fee calculated by Building Code Services staff, and receive the issued permit
- Book inspections through My ServiceOttawa as construction proceeds
What does a Ottawa ADU permit application need?
- Signed digital building permit application + Schedule 1: Designer Information
- Fully dimensioned site plan — building location, distances to lot lines, zoning provisions, easements, and an unobstructed egress path to the street
- Grading plan — required on rural lots, when the building area exceeds 55 m², or when building within 1.2 m of a property line
- Foundation plan with footing details and frost protection
- Floor plans for each storey (room dimensions, ceiling heights, window-area calculations, fire separations, HVAC) plus cross-sections and assembly specifications
- On private-serviced lots: Ottawa Septic Office (OSSO) documentation confirming the septic system can absorb the added load
How much does an ADU building permit cost in Ottawa?
Ottawa charges permit fees per m² of new gross floor area by a published Service Index rate (minimum $117, 2026 schedule) rather than one flat coach-house number — confirm the current rate with Building Code Services and treat any total as an estimate, not a quote.
| Permit fee | Service Index rate per m² of gross floor area (City fee schedule); minimum $117 (2026) |
|---|---|
| Development charges | Coach houses are exempt from municipal development charges (since September 18, 2020) — but Education Development Charges still apply |
| Minor variance (only if needed) | A separate Committee of Adjustment application fee when the design doesn't meet the by-law as-of-right |
| Septic review (rural lots) | Separate Ottawa Septic Office fee for a new or shared septic approval |
A coach house is exempt from municipal development charges (in effect since September 18, 2020), but not from Education Development Charges, which still apply.
How long does an ADU building permit take in Ottawa?
Ontario's Building Code requires a decision on a complete house-class application within 10 business days. The 10-business-day window applies only once the application is deemed complete — and a design needing a Committee of Adjustment variance adds a separate, longer approval track before permit review even begins.
Worth knowing before you apply
- Ottawa is mid-transition between Zoning By-law 2008-250 and the new By-law 2026-50 — the MOST RESTRICTIVE provisions of the two apply to applications deemed complete on or after March 11, 2026, so a coach house that looks permitted under the new by-law can still be constrained by the old one
- Servicing caps the unit count: municipal water+sewer allows up to two additional units, but a private-serviced (well/septic) lot is capped at ONE additional unit — and OSSO must confirm septic capacity before a permit issues
- A rural coach house needs a lot of at least 0.8 ha on private services shared with the main house; a privately-serviced lot over 0.4 ha also triggers Site Plan Control
- Grading plans are needed more often than people expect — any coach house over 55 m² or within 1.2 m of a lot line, not just rural builds
- Lots near a watercourse, wetland, steep slope, or floodplain may also need a conservation-authority permit (RVCA/MVCA/SNC) on top of the building permit
- No new parking is required — but a voluntarily added space can't sit in the front yard
Fees and timelines are estimates from Ottawa's published schedules, verified July 4, 2026. Rates and processes change — always confirm current requirements with the building department before you apply.
Grants & financing in Ottawa
See every program → Ontario ADU Grants Directory
A modular or prefab home on a permanent foundation is financed like any house. CMHC Prefab Plus allows an insured mortgage with as little as 5% down on the first $500,000, with construction funds released in stages. How modular home financing works →
Thinking of the suite as a rental? Run the numbers →
Ottawa modular homes — FAQ
Can you put a coach house (ADU) in Ottawa?
Yes. Ottawa permits a detached “coach house” on most residential lots with a house, as-of-right — subject to the size, height, and setback rules and a building permit.
How big can a coach house be in Ottawa?
Up to 80 m² (≈860 sq ft) in urban/suburban zones (95 m² / ≈1,025 sq ft rural), but during the current by-law transition the binding limit is often 40% of your home’s footprint — so the real number depends on your house and lot. Check your address for the exact figure.
Can you put a modular home in Ottawa?
Yes. On land you own, a modular home on a permanent foundation is legal residential housing under the Ontario Building Code throughout Ottawa, subject to standard zoning and permits.
How much does a modular home or backyard suite cost in Ottawa?
Modular home models start at $175,696 and run to about $338,000 for the largest layouts; backyard ADU models start at $96,244. Site work, foundation, delivery, and permits are additional.
Can I get a mortgage on a modular home in Ottawa?
Yes — on a permanent foundation it is financed as real property, including via CMHC Prefab Plus (5% down on the first $500,000).
Local rules summarized from Ottawa Zoning By-law 2008-250 §133, plus the new By-law 2026-50 §701 — the most-restrictive provisions of both apply during the transition; verified by Modular Homes 400 and reviewed by James Clarke, REALTOR®. Always confirm current requirements with the City of Ottawa before you build.