Every service we offer, in one place.
Detached, above or beside parking
Builds up over your garage instead of into the yard.
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Detached, lane access
Its own entrance and street presence off a rear lane.
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Zoning and Committee of Adjustment
Bring an existing unit up to code and on title.
Learn moreWe confirm what your lot's zoning actually permits before design work starts.
Architectural drawings, engineering where required, and the City of Ottawa building permit filing.
One team stays accountable from design through final inspection.
Most homeowners land on this page comparing two or three options rather than certain which one they want. That is exactly what a feasibility review is for: we look at your specific lot, tell you honestly which of these four types it actually supports, and give you a realistic sense of size, cost, and timeline for each of the realistic paths before you commit to a direction, in plain language rather than zoning jargon.
The City of Ottawa's zoning by-law recognizes four practical ways to add a second home to a residential property, and this page is the starting point for all of them. Which one makes sense for your lot depends on things a calculator or a general article cannot tell you: your property's specific zoning, how much of it is already built on, whether your basement clears the minimum ceiling height, and whether you have a garage or a rear lane to work with.
Both a garden suite and a coach house are fully detached structures, separate from the main house, which means real privacy for both households and no impact on the main house's existing living space. The difference is placement. A garden suite sits in open yard space. A coach house sits above or beside a garage, which matters on a lot where yard depth is tight but an existing or planned garage footprint has room to build up. A laneway suite is a close cousin of both, specifically oriented toward a rear service lane where one exists.
For a large share of Ottawa properties, especially older housing stock without much rear yard depth, a basement apartment conversion is the most realistic option. It uses a foundation that already exists, which generally makes it the fastest and lowest-cost-per-square-foot ADU type to build, provided the basement clears (or can be brought up to) the minimum ceiling height and can be given a proper second exit.
Every one of these paths goes through the same core steps: a feasibility review against your property's actual zoning, design and permit drawings prepared to Ontario Building Code requirements, a City of Ottawa building permit application, and construction carried out by a crew working from the approved drawings. We run all of it under one contract, so the same team that designs your unit and files the permit is the one building it.
On many Ottawa residential lots, up to three dwelling units total (the main house plus two ADUs) are permitted as-of-right, subject to lot size, parking, and servicing. Zoning varies by property – a feasibility check confirms your lot's limit.
A basement apartment conversion is usually the lowest cost per square foot because it reuses an existing foundation and walls. Detached units (garden suite, coach house, laneway suite) cost more per square foot but do not reduce the livable space in your main house.
Not every project starts from a blank slate. If your property already has a basement apartment, a garden suite, or a coach house that was never permitted, the process is a review of what exists against current code, followed by targeted upgrades and a retroactive permit application, not necessarily a full rebuild. Our legalization service covers that path specifically.