Home/Modular Homes by City/Cambridge
Serving Cambridge & Waterloo Region
Modular Homes & Garden Suites in Cambridge, Ontario
Factory-direct modular homes and backyard suites for Cambridge and Waterloo Region. Here's what Cambridge's new additional-residential-unit by-law allows in your backyard, what it costs, and the rules that apply.
What you can build in Cambridge
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 Cambridge'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 Cambridge 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? (Cambridge lots typically allow up to ~900 sq ft)
Cambridge caps a detached suite at the lesser of 100 m² (≈1,076 sq ft) or 15% lot coverage. Your exact lot may allow more or less — get the real number for your address in seconds.
Check your exact Cambridge address →Can you put a garden suite (ADU) in your Cambridge backyard?
Often, yes — Cambridge permits a detached Additional Residential Unit on most serviced residential lots. The specifics, from City of Cambridge Zoning By-law 26-007 §4.19 (Additional Residential Units), in force after February 3 2026:
| Max size | The lesser of 100 m² (≈1,076 sq ft) or 15% lot coverage |
|---|---|
| Max height | 4.5 m (≈15 ft) — up to 6.0 m (≈20 ft) where the lot has ≥21 m (≈69 ft) frontage or lane access |
| Setbacks | 1.2 m (≈4 ft) side · 1.2 m (≈4 ft) rear (0.6 m / ≈2 ft with lane access) · 4.5 m (≈15 ft) separation from the main house |
| Units per lot | Up to 2 ARUs — at most one detached — on single-detached, semi, or street-townhouse lots (RR/R1/R2/R3) |
| Parking | 1 space per ARU |
| Servicing | Connect to municipal water & sewer where available; private servicing only where municipal is genuinely unavailable and capacity is proven |
| Conservation | Grand River Conservation Authority (GRCA); not permitted in the Floodway or any Floodplain Overlay |
Check your specific Cambridge address →
Garden suite, laneway suite, in-law suite, ARU, ADU — different names for the same thing: a small, self-contained home in the backyard. New to the idea? Start with prefab garden suites for Ontario — what one costs in Cambridge, and the models that fit →
Cambridge's by-law is verified in our checker, so you can check if a garden suite is allowed at your Cambridge address in about a minute.
Getting your building permit in Cambridge
An eligible lot still needs a building permit before anything is delivered. Here's how Cambridge's process actually works — verified against the Cambridge building department's own pages.
How do you apply for an ADU building permit in Cambridge?
Through City of Cambridge Online Applications portal (Clariti) (application portal ↗). Run the project through the Cambridge Application Navigator first (app.oncamino.ca/cambridge) to compile the document checklist, then submit, track, and pay through the Online Applications portal at permits.cambridge.ca. Cambridge's building-permit page ↗
- Pre-check zoning with planning@cambridge.ca — a detached ARU is as-of-right only in the RR1/RR2/R1–R4 zones
- Run the project through the Application Navigator to confirm the permit type and required documents for your property
- Prepare the drawings and forms with a qualified designer (identified on Schedule 1)
- Register on the Online Applications portal and submit the complete package
- A Building Official invoices the permit fee after review — pay it for the application to be considered complete
- The permit issues listing all required inspections; book each with the assigned inspector at least 24 hours ahead
- Pass the final inspection and receive occupancy approval from Building Services before the unit is occupied
What does an ADU permit application in Cambridge need?
- Application for a Permit to Construct or Demolish (the provincial form)
- Schedule 1: Designer Information + the residential permit information form
- Complete drawing set showing compliance with Zoning By-law 26-007 §4.19 (setbacks, parking, unit size, entrance location)
- Heat-loss/heat-gain calculations and the Energy Efficiency Design Summary
- Sewage-system design + Schedule 2 (installer information) where the lot is on private septic
How much does an ADU building permit cost in Cambridge?
Cambridge calculates permit fees from a per-m² construction formula with a $143 minimum for Part-9 residential work (2026 schedule) — the exact per-m² rate wasn't published in a fetchable form, so get an estimate from the Building Division (519-623-1340 ext. 4070) before budgeting; the good news is the City and Region collect no development charges on ARUs.
| Permit fee | Per-m² residential construction formula; $143 minimum for a Part 9 residential structure (2026 schedule) — confirm the current rate with the Building Division |
|---|---|
| Re-inspection fee | $100 where a failed item needs another visit |
| ARU incentive grant | Up to $10,000 for service upgrades, permit drawings, and construction costs (launched Nov 2024) — confirm current intake before counting on it |
The City of Cambridge and Region of Waterloo collect no development charges on additional residential units — school-board charges can still apply in some cases, so confirm with Planning.
How long does an ADU building permit take in Cambridge?
Ontario's Building Code requires a decision on a complete house-class application within 10 business days. The clock starts only once the application is complete AND the invoiced fee is paid — and a GRCA-regulated lot adds the conservation authority's own 4–6-week review on top.
Registration: No separate ARU registration or renewal — occupancy approval at final inspection is the close-out step.
Worth knowing before you apply
- Lots near the Grand or Speed rivers, a watercourse, wetland, or the floodplain need a SEPARATE Grand River Conservation Authority permit — GRCA's review runs about 4–6 weeks outside the City's timeline; check GRCA's Map Your Property tool early
- The Application Navigator step is worth doing — it produces the property-specific document checklist that keeps the submission from bouncing
- The $10,000 ARU grant is applied for separately through the portal under "Financial Incentives" — verify the program is still taking applications first
- Small storage sheds are permit-exempt, but a habitable ARU always needs a full permit regardless of size
Fees and timelines are estimates from Cambridge's published schedules, verified July 4, 2026. Rates and processes change — always confirm current requirements with the building department before you apply.
A garden suite on a well and septic in Cambridge
Can I add a garden suite on a septic system in Cambridge?
Yes, if your septic system can carry the house and the suite together. A garden suite with a kitchen and bathroom adds a new source of sewage, so a qualified septic designer checks the combined load before you order. If the system has room, the suite can connect to it; if not, it may need to be altered, expanded or replaced.
In Cambridge: The septic check has to be in writing (a septic capacity letter) before the building permit is issued.
Who approves septic systems in Cambridge?
The City of Cambridge Building Services approves septic systems itself, so the septic review and the building permit both go through the municipality.
City of Cambridge Building Services: septic permits ↗ · 519-623-1340 · building@cambridge.ca
What to gather, and why even a small suite needs the check: our guide to garden suites on a septic system →
From City of Cambridge Building Services’s own page, checked October 24, 2026. Confirm with them before you apply.
Grants & financing in Cambridge
Region of Waterloo — Ontario Renovates — Secondary Suites (open) — An interest-free loan of up to $25,000, forgiven over 15 years, to create a secondary suite rented at average market rent to an income-qualified tenant. Details →
City of Cambridge — Additional Residential Unit Financial Assistance Program (open) — A one-time grant of up to $10,000 toward servicing upgrades, permit drawings and construction costs, claimed after the ARU is built and has its occupancy approval. Details →
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 →
Cambridge modular homes — FAQ
Can you put a garden suite in Cambridge?
Yes. Cambridge permits up to two additional residential units (at most one detached) on lots with a single-detached, semi, or street-townhouse home in the RR/R1/R2/R3 zones — subject to the size, height, and setback rules and a building permit.
How big can a garden suite be in Cambridge?
A detached ARU is capped at the lesser of 100 m² (≈1,076 sq ft) or 15% lot coverage. Check your address for the exact number.
Can you put a modular home in Cambridge?
Yes. On land you own, a modular home on a permanent foundation is legal residential housing under the Ontario Building Code throughout Cambridge, subject to standard zoning and permits.
How much does a modular home or backyard suite cost in Cambridge?
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 Cambridge?
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 City of Cambridge Zoning By-law 26-007 §4.19 (Additional Residential Units), in force after February 3 2026; verified by Modular Homes 400 and reviewed by James Clarke, REALTOR®. Always confirm current requirements with the municipality before you build.