How Much Does a Basement Suite Cost to Build in Alberta and BC?

This guide is written for Alberta and British Columbia, where the term is “basement suite.” (In Ontario and the GTA it’s a “basement apartment,” the code differs, and there’s a separate guide for it.)

What it costs in Calgary, Edmonton and BC

We could not source a defensible range for any of the three markets, so we’re not publishing one. The figures circulating are single-contractor, unsourced, or American, and the variance between a finished basement and a bare one is wider than any published range admits.

What we can give you precisely are the published municipal fees, because Calgary publishes them:

Two things follow. The permit is not the cost — a few hundred dollars against a project costing many multiples of it. And registration is free, which given what a registered suite unlocks is the best-value step in the process.

Edmonton and BC municipalities publish their own schedules; look yours up rather than assuming Calgary’s apply.

The cost drivers

1. Ceiling height — and it differs by province.

• Alberta: minimum 1.95 m within the suite and above stairs, reducible to 1.85 m below ductwork and beams
• British Columbia: minimum 2 m, including under beams in passageways

That 50 mm matters. A basement that would legalise in Calgary or Edmonton may fail in Vancouver or Surrey. If you’re reading Alberta guidance for a BC project, this is the first thing that will catch you out.

Where you’re short, the fix is underpinning or lowering the slab — structural work with engineering, and the single biggest cost risk in a basement conversion. Measure before anything else.

2. Egress windows. Both provinces require an unobstructed openable area of at least 0.35 m² with no dimension under 380 mm, openable from inside without keys or tools. BC additionally limits the sill to 1 m above the floor — stricter than Ontario’s 1.5 m. Where the window opens into a well, at least 760 mm of clearance in front.

Below grade this means cutting the concrete foundation and excavating a well. Real work, defined scope, far cheaper than underpinning.

3. Fire separation — and a BC saving worth knowing.

• Alberta: a smoke-tight separation between the main residence and the suite, and in common spaces and the furnace room. Doors in those locations must be solid core wood at least 45 mm thick with a self-closing device.
• British Columbia: 45 minutes — reduced to 30 minutes where additional photo-electric smoke alarms are installed in each unit and interconnected.

That BC trade-off is a genuine cost lever: adding interconnected photo-electric alarms is usually much cheaper than building to the higher rating.

4. Separate entrance — and a possible saving. Cutting a below-grade entrance means excavation, concrete, a stairwell and drainage. But Calgary accepts a shared stairwell where each unit has its own private entrance off a common landing — often far cheaper. Check your municipality before budgeting for excavation.

5. Alarms, plumbing and electrical. Hardwired interconnected smoke alarms across both units plus CO alarms. A second kitchen commonly triggers an electrical service review.

6. Zoning items that aren’t construction at all. In Calgary, a secondary suite requires one parking stall for the tenant in addition to the property’s own requirement — with published minimum dimensions, and street parking and tandem stalls behind other required stalls don’t count. Calgary also requires outdoor amenity space of at least 7.5 m² with no side under 1.5 m.

Neither is something a builder can solve. Both can stop a project. Resolve them on paper first — our Calgary building guide covers them.

The province gap

The same basement, the same work, priced differently — and it’s mostly not construction.

Being honest about the size of the PST effect: it applies to materials rather than to the whole project, so it isn’t 7% of your total build. On a suite where materials are a substantial share of cost, it’s a real number but a smaller one than “7% of the project” would suggest. We’re not going to quantify it further without a sourced materials-to-labour split.

BC’s DCC position is genuinely local. Statutory exemptions are narrow — units no larger than 29 m², or permits for work not exceeding $50,000 — but municipalities may waive or reduce charges, and many BC bylaws do exempt one secondary suite in a single-family dwelling. Check your bylaw; don’t assume either way.

And BC’s ongoing cost: in Surrey, once a suite is registered, secondary suite utility and service fees are applied to your annual property taxes, in addition to the single-family rate for water and sewer. That’s an operating cost, not a build cost, and it belongs in your rent calculation.

Net: Alberta is the lower-cost province for adding a suite, and the advantage is structural rather than programmatic. Our Edmonton and Vancouver building guides cover each market.

Legalising an existing suite

Usually far cheaper than building new — and Calgary’s published numbers make the point.

$205.92 for the building permit, with the City giving an approval timeline of approximately seven days for that review, and registration free.

The variable is the remedial work, which falls into three tiers:

• A weekend — interconnected smoke and CO alarms, a solid-core self-closing door on the furnace room
• A moderate project — enlarging an egress window (cutting concrete, excavating a well) plus fire separation
• A structural project — underpinning to gain ceiling height

Assess in that order — height, then egress, then separation — and you’ll know within an hour which tier you’re in.

Rent and payback

Get your market’s figure from CMHC’s Rental Market Report, then adjust downward for a below-grade unit. Subtract vacancy — rates across major Canadian centres rose through 2025 and into 2026 — plus maintenance, insurance, tax on the rental income, and any ongoing municipal fees.

On payback: net rent against your increased carrying cost, over the hold period you actually expect. A basement suite is the fastest-paying ADU because it’s the cheapest, but it’s still a multi-year proposition.

Incentives, stated accurately

Because this is routinely misreported:

Calgary’s Secondary Suite Incentive — up to $10,000 for qualifying safety elements, plus up to $7,500 for accessibility and $1,900 for ENERGY STAR equipment. Waitlisted as of 24 June 2026, applies only to suites within the main dwelling, requires you to apply before starting work, and carries a two-year short-term-rental restriction.

BC’s Secondary Suite Incentive Program — closed to new applications after 30 March 2025. Not reinstated.

The federal $80,000 loan — cancelled, never operational.

Alberta’s SHARP and RAMP — SHARP is a seniors’ home-equity loan for their own residence; RAMP is an accessibility grant with strict medical and income tests. Neither funds a rental suite, despite frequently appearing on “Alberta suite grant” lists.

What does apply: CMHC’s refinance product at up to 90% of as-improved value on properties with up to four units, and the MHRTC where the occupant is a qualifying relative.

Find out what your basement would need

Ceiling height, egress and — in Calgary — parking and amenity space decide this, and all four are checkable before you spend anything.

HouseLyft’s free property assessment establishes where your property stands. Request your free report.