My new house has a capped radon pipe — is radon already handled?

No. The rough-in is preparation, not protection — a capped stub does not move soil gas. The code stops at the rough-in — a fan isn't required — and national guidance recommends sizing and installing the fan after occupancy, with proper diagnostics. Test first; activate if your long-term result is above 200 Bq/m³.

Do all new homes in Canada have a radon rough-in?

The national code has required it since 2010, and current provincial codes in BC (2024, province-wide), Alberta, Ontario (2024 code), Quebec (since 2020) and NBC-following provinces include it. Older homes, and homes permitted before each code took effect, may not have one.

Can I activate a radon rough-in myself?

The mechanical work — fan, couplings, cord, manometer, short discharge run — is within reach of a capable DIYer since the slab work is already done, and about $490 in core parts. Health Canada recommends C-NRPP certified professionals for mitigation, and a pro also brings diagnostic testing to size the fan correctly. Either way, verify with a retest.

How much does the fan raise my power bill?

Health Canada pegs radon fan electricity at roughly $50–$75 per year, depending on fan size and rates. The fan runs continuously and should never be switched off.

How to Activate a Radon Rough-In (Canada)

If your home was built in roughly the last decade, there's a good chance a capped PVC pipe is sticking out of your basement floor with a label saying it's for radon. That's your radon rough-in — required by Canada's National Building Code — and it's the cheapest head start on radon protection a homeowner can get. It is also doing nothing until it's activated. Here's what it is, when to activate it, and exactly what that takes.

What That Capped Pipe Actually Is

The National Building Code's soil gas control provisions (NBC 2020, s. 9.13.4) require new homes with conditioned space touching the ground to include an air barrier against the soil plus a rough-in for a radon extraction system: one of two compliance paths: a gas-permeable layer with an inlet and outlet, or — the common path — clean granular fill under the slab plus a pipe at least 100 mm (4") in diameter through the floor, bottom end open in the gravel near the centre of the slab, top end fitted with an airtight cap and labelled as intended only for removing radon from below the floor. The rough-in requirement entered the national code in 2010, per Health Canada, and has spread through provincial codes since:

BC: the Building Code 2024 requires the rough-in province-wide (permits from March 8, 2024), ending the old list of designated municipalities. BC's bulletin describes the rough-in as “a pipe that is ready for the installation of a fan.”
Alberta: included since the NBC – 2019 Alberta Edition; the current NBC – 2023 Alberta Edition (in force May 1, 2024) is based on NBC 2020.
Ontario: the 2024 Building Code (in effect January 1, 2025) adopts NBC 2020's soil-gas provisions — municipal building departments such as Ottawa's now require the soil gas barrier, rough-in, and whole-house ventilation on all new Part 9 homes.
Quebec: the Construction Code has required the rough-in since September 2020 — and goes further, requiring radon test results be submitted and sub-slab depressurization completed where results show the need.
Most other provinces and territories follow the National Building Code's rough-in provisions, per Health Canada's adoption table.

And the code is still tightening: the NBC 2025, published December 22, 2025, adds a requirement for a passive vertical radon stack in new dwellings — a full vent pipe run, not just a stub — applying as provinces adopt the new edition. A fan is still not required by the model code. The direction of travel is clear: Canadian codes are building homes radon-ready and leaving the last step — the fan — to you.

Step 1: Test First. Always.

A rough-in is not a mitigation system — the model code stops at the rough-in and does not require a fan. Take Action on Radon recommends the full system (with a properly sized fan) be installed once the home is occupied so proper diagnostics can be done. The decision to activate comes from a test: Health Canada specifies a long-term test of at least 91 days, with a minimum of 91 days during the heating season, placed in a normal occupancy area of the lowest lived-in level. If your average exceeds 200 Bq/m³, current guidance is to mitigate within 1 year — sooner for higher levels. Our $60 long-term alpha track kit is a C-NRPP-approved alpha track device and the way to get that number; newly built homes should be tested in the first heating season after occupancy per Health Canada's measurement guide. More on protocol in our test kit guide.

The Three Levels of Radon Control

CARST describes new-construction radon control in three levels: Level 1 is the rough-in you have; Level 2 adds a full passive vertical stack, which typically reduces radon by about 50%; and Level 3 — the rough-in plus stack plus a continuously running fan — is the most effective, often cutting high radon levels by 90% or more. Activating your rough-in gives you the equivalent of a Level 3 system — a full active sub-slab depressurization setup, the configuration CARST's 90%-plus figure describes — and Health Canada calls the resulting system (active sub-slab depressurization) the most effective and reliable radon reduction technique there is.

Step 2: What Activation Takes

Because the builder already did the slab work — the gravel layer, the sealed penetration, the pipe — activation is the light half of a mitigation job. The pieces (each requirement below is from Health Canada's Reduction Guide, the BC code bulletin, or RadonAway's installation instructions — assembled here as one list):

A radon fan sized to your house. Sub-slab conditions, not horsepower, pick the fan — see how to choose a radon fan. For typical homes the RP145 is the starting point; tight clay soils call for the GX series.
Flexible couplings (×2) — RadonAway's instructions call for completing the piping with flexible couplings for service disconnect and vibration isolation. The fan mounts vertically, outlet up.
A u-tube manometer or audible alarm — required per manufacturer instructions to tell occupants the fan has failed. Unequal fluid levels = working; equal = not. The RSA1 alarm does the watching for you.
A power cord kit — RadonAway fans ship without one. (BC's bulletin recommends builders rough in a receptacle within 1.8 m of the fan location — check yours.)
PVC cement and discharge parts for the vent run — in Canadian climates the smart discharge is short and near grade; see why Canadian systems are built to survive winter.
Labels and a baseline. Health Canada: label the system with the activation date and re-test intervals, and record the suction reading so future checks have a comparison point.

That's roughly $490 in core parts at our current prices — the full arithmetic is in our mitigation cost breakdown — or one pass through the kit builder, which assembles fan, couplings, manometer, and add-ons in one click.

Or have a pro do it. Health Canada recommends hiring a C-NRPP certified professional for mitigation work — activation included — and with the rough-in already in place, you're paying for the light end of the $2,000–$3,000 range Health Canada has published for a full sub-slab install (figures that predate current market pricing). Quebec homeowners should note their code expects it. Find a certified mitigator here.

Step 3: Prove It Worked

Health Canada's verification sequence: a short-term check by a certified professional starting at least 24 hours after the fan comes on; a re-test the next heating season; an initial long-term measurement within two years of activation; then every 5 years to confirm the system keeps performing. Keep the manometer's labelled baseline in view — any sustained change means the system needs attention.

Frequently Asked Questions

My new house has a capped radon pipe — is radon already handled?: No. The rough-in is preparation, not protection — a capped stub does not move soil gas. The code stops at the rough-in — a fan isn't required — and national guidance recommends sizing and installing the fan after occupancy, with proper diagnostics. Test first; activate if your long-term result is above 200 Bq/m³.
Do all new homes in Canada have a radon rough-in?: The national code has required it since 2010, and current provincial codes in BC (2024, province-wide), Alberta, Ontario (2024 code), Quebec (since 2020) and NBC-following provinces include it. Older homes, and homes permitted before each code took effect, may not have one.
Can I activate a radon rough-in myself?: The mechanical work — fan, couplings, cord, manometer, short discharge run — is within reach of a capable DIYer since the slab work is already done, and about $490 in core parts. Health Canada recommends C-NRPP certified professionals for mitigation, and a pro also brings diagnostic testing to size the fan correctly. Either way, verify with a retest.
How much does the fan raise my power bill?: Health Canada pegs radon fan electricity at roughly $50–$75 per year, depending on fan size and rates. The fan runs continuously and should never be switched off.