What Happens During a Radon Mitigation Installation, Step by Step
By First Choice Radon · Updated September 2, 2026 · 9 min read
Knowing what happens on installation day makes the decision easier. This is the process we follow, from the first suction test to the retest that proves your radon level has dropped.
Typical time for a certified professional to install a system.
Radon reduction possible in most homes.
Bq/m³ is the guideline the retest checks against.
The installation, step by step
Most radon systems use sub-slab depressurization, also called active soil depressurization. A fan creates suction beneath the floor, pulls soil gas out before it can enter, and sends it outside through sealed pipe. Health Canada and Take Action on Radon both describe it as the most common method.
1. Communication test
We test how far suction spreads under the floor. The result tells us where the suction point should go and whether more than one is needed.
2. Core the floor
We core a hole through the floor at the chosen spot and hollow out a small pit beneath it, which helps suction spread.
3. Run the pipe
A vent pipe is fitted into the hole and run to the outside. All joints are sealed so the system does not connect to indoor air.
4. Mount the fan
The fan is mounted inside on the pipe, usually right above the core-drilled hole. It needs power, so the installation includes the electrical connection.
5. Exit and seal
The pipe exits through the side of the building, clear of windows, doors and air intakes. Openings around it and visible cracks in the floor are sealed.
6. Gauge and check
A manometer, a small gauge on the pipe, shows suction is active. We check the system is running before we leave.
What a radon system is made of
Suction point
The cored hole and pit under the floor where soil gas is collected.
Vent pipe
Sealed pipe that carries soil gas from beneath the floor to the outside.
Radon fan
A fan designed for radon use that runs continuously to keep suction active.
Manometer
A gauge that shows at a glance that suction is working.
Sealing
Caulk and sealant on cracks, gaps and the pipe penetration so suction reaches the whole area.
Extras when needed
A sealed membrane over exposed crawlspace soil, an airtight lid on a sump pit, or a second suction point where one cannot cover the floor.
After installation: the retest and what comes next
Installation is not finished until the result is proven. We retest afterward to confirm the radon level has dropped. In most homes a system can reduce radon by up to 95%.
- Retest. Health Canada advises retesting after installation and again every five years after that.
- Check the gauge. If the manometer reading changes noticeably, contact your installer, because it can mean the fan needs attention.
- Keep the records. Keep the quote, the before and after results and the fan details, which is useful if you sell.
Starting from $1,799, mitigation is quoted in writing before any work begins. The $99 test is reimbursed on a mitigation quote if you choose First Choice Radon.
Where the vent pipe is allowed to end
Where the pipe terminates matters, because it releases soil gas outdoors. An Alberta building interpretation on soil gas vents sets these limits for systems built on a rough-in:
- The vent must end in outside air.
- Not less than 300 mm above grade.
- Not within 300 mm of an openable window or door.
- Not within 1.8 m of a mechanical air-supply inlet.
- If vented above the roof, at least 150 mm above the roof or any ponding stormwater.
These points are why our pipe exits through the side of the building clear of windows, doors and air intakes. They are also why a C-NRPP certified installer is the safer choice.
What you need to do
Very little. You do not need to prepare the building. We need access to the area where the suction point will go and a path for the pipe. You can stay at home during the work, and we explain the system and the gauge before we leave.
Installation steps questions
How long does radon mitigation installation take?
A certified professional can typically install a system in about one day. That includes the suction point, pipe, fan, sealing and a check that the system is running. We retest afterward to confirm the level has dropped.
How does a radon mitigation system work?
A fan creates suction beneath the floor through a core-drilled hole and pit. Soil gas is pulled out before it can enter and vented outside through sealed pipe. The method is called sub-slab depressurization.
Where does the radon fan go?
At First Choice Radon the fan is mounted inside on the pipe, usually right above the core-drilled hole. The pipe exits through the side of the building, clear of windows, doors and air intakes.
What is a communication test?
It is a test of how far suction spreads under the floor. The result shows where to place the suction point and whether more than one is needed.
How do I know my radon system is working?
A manometer, a small gauge on the pipe, shows suction is active, and a retest after installation confirms your radon level has dropped. Health Canada advises retesting after installation and every five years after that.
How much does radon mitigation installation cost?
Mitigation with First Choice Radon starts from $1,799 and is quoted in writing before any work begins. The price depends on the building, including the floor, any crawlspace or sump pit and the pipe route.
Does the radon fan run all the time?
Yes. The fan runs continuously to keep suction active. The manometer on the pipe shows it is running.
Book a mitigation assessment
Get a written radon mitigation quote from C-NRPP certified professionals. Serving Cochrane, Calgary and surrounding Alberta communities. See our pages for Calgary, Cochrane, Okotoks, Airdrie.
Sources: Health Canada: Radon, it’s in your home; Take Action on Radon: reducing radon; Alberta Building Interpretation 19-BCI-013; Health Canada: Radon.
More radon guides
Radon in Cochrane, Alberta: What to Know and How to Test
What studies found in Cochrane, how a 91-day test works, and what to do about a high result.
October 28, 2026Radon Mitigation Cost in Alberta (2026 Guide)
What a radon system costs, what changes the price, and how to compare quotes.
October 14, 2026Radon Test Results Explained: Bq/m³ and pCi/L
What your radon number means, the 200 Bq/m³ guideline, and what to do next.