Radon for condo boards

What does a board have to settle before any unit is tested?

Who arranges the tests, who receives the reports and who pays. We cannot answer any of the three. Whether a foundation slab is common property, whether the corporation or the owner arranges a test, and how a cost is shared are questions for the corporation's lawyer or its manager.

A board is in a different position from a landlord. The people it decides for own their units and live in them, so a detector goes into an owner's home and the result describes that owner's air. What we can offer is a list of the questions that tend to come up, so a board can take them to the right adviser before the first detector is ordered:

• Does the corporation organize the round of tests, or does it encourage owners to test their own units?
• Who receives each laboratory report: the owner, the board, or both?
• If a unit is high, who approves a pipe that passes through common property?
• Who maintains a system once it is installed, and who retests?
• How are tenants in rented units told about the test and its result?

A board that settles these first knows what will happen to a number before the number exists.

Where should a first round of tests begin?

With the homes that sit on or in the ground. In a townhouse-style complex that is usually every unit, since each has its own basement or slab. In a low-rise building it is the ground-level and below-grade units.

Health Canada's guide places the detector in a regularly occupied room on the lowest lived-in levelsource, and in those units that level rests on the foundation. The reasoning behind the order is given in full on our page for managers of rental portfolios, and it holds for a complex of owners as it does for a list of rental addresses.

Boards sometimes ask whether location in the city changes the order. Nothing published gives a board a reason to change it. Results from the Cross-Canada Survey of Radon Exposure put about 1 in 6 houses in the Calgary area (15.5%) at or above 200 Bq/m³source. The University of Calgary-led study published in 2017 found about 1 in 8 homes tested in Calgary and area at or above Health Canada's guidelinesource. Neither figure is specific to condominiums, and neither singles out a quadrant a board could treat as exempt. What is published about geography is summarized on our Calgary radon map page.

Does a result from one unit describe the unit beside it?

No. Radon levels vary from one home to the next, even between similar houses next door to each other, and only a test makes anyone sure of a home's levelsource.

Townhouse rows invite the opposite assumption, because the units look identical and were built in one project. A low result at the end of a row does not clear the middle of it. A high result in one unit is not evidence about the rest, though it is a sensible prompt for the neighbours to test. We know of no sound way to test a few units and assign their numbers to the others, and we will not prepare a report that does so.

Do upper-floor units need a test?

Health Canada's recommendation does not leave them out, although a board working in stages would not begin with them. Health Canada recommends a radon test for every home, regardless of where it is located or what type of building it issource.

We have no sourced figure for how levels change with height in a building, so we state none. What can be said is narrower. The measurement guide looks to the lowest lived-in level, and that justifies an order of work. It does not justify telling an upper-floor owner that their unit has been cleared. An owner on any floor who wants a number can place a kit, and the page on radon test kits available in Calgary compares them.

What about hallways, parkades and other common areas?

The residential method measures where people live, so it does not transfer neatly to spaces people only pass through. We do not stretch it to fit, and we do not offer measurement of non-residential space at present.

A board may come across another federal document while reading. Health Canada publishes a separate measurement guide for public buildings, meaning schools, hospitals, care facilities and detention centressource. A residential condominium is not on that list. For a condo unit we work from the guide for homes, with its test in a room someone occupies for hours each day, and you can ask us why if your building is unusual. If your building includes shops or offices on the ground floor, that part is outside what we do, and it is better to hear that now.

How can a board organize a round of tests?

As one coordinated project over a single heating season. Health Canada recommends measuring for 3 to 12 months, with 91 days as the minimumsource. It asks that at least 91 days of the test fall within the heating season, the period when windows are closed and indoor radon tends to be highestsource. Its advice is to test for at least three months, ideally between October and Aprilsource.

However the round is organized, each result stands for its own unit only. The stages inside a single test are described on our long-term radon testing page, and the guide to testing a home for radon suits owners who place their own kit.

How should results be shared with owners?

By unit, in writing, under a rule the board has agreed on beforehand. A result describes one home, and the person living there has the most direct interest in it.

As general guidance, an owner should receive the full laboratory report for their own unit and not just a figure. A summary for the whole complex should count units and never blend them into one number, since a figure for the building tells an owner nothing about the air in their own home. Whether unit numbers appear in board minutes, and what a seller later has to disclose, are matters for the corporation's lawyer. Owners can place their number with the test result checker and read what Canadian radon guidelines say about each range.

What happens when a unit is above the guideline?

Mitigation is recommended for that unit. In a condominium the owner should check with the corporation before work starts; whether its consent is needed is a question for its lawyer or manager. Canada sets its radon guideline for indoor air at 200 Bq/m³, and Health Canada recommends corrective action for an annual average above itsource. Above 200 Bq/m³ it recommends mitigating within one year, and sooner the higher the level, reducing levels as low as reasonably achievablesource.

Health Canada recommends action above the guideline, not below it. Below the line the decision sits with whoever owns the unit, and the plain facts remain that lower is better and no level is risk-free.

Health Canada describes sub-slab depressurization as the most common and effective method, and says that increasing ventilation and sealing entry routes have limited effect on their ownsource. Health Canada says a radon reduction system can usually be installed in less than a day and, in most homes, reduces radon by more than 80%, at a cost comparable to other common home repairssource. For a townhouse-style unit the standard arrangement is a fan on the pipe inside the basement and an exhaust through the rim joist at the side wall. Some layouts take the pipe up an interior route to above the roof instead. Either way the pipe crosses an exterior wall or a roof. Whether that surface belongs to the unit or to the corporation is not ours to say, so it helps a board to decide in advance how it will handle a request of that kind.

Whether one system can serve more than one unit is a design question that depends on what lies under the slabs and how the foundations are divided. It cannot be answered from a drawing or promised ahead of a site assessment. The general method is described on the page about radon mitigation in Calgary.

Should radon appear in reserve fund planning?

That is the board's decision, taken with its reserve fund adviser, and we give no financial or legal opinion on it. What testing contributes is information a planner can use.

Three sourced points are relevant. A system has a moving part. According to Health Canada's Radon Reduction Guide for Canadians (2014), a radon fan's lifespan can vary between five and ten or more yearssource. A system also brings a recurring test. Health Canada recommends that a home with an active mitigation system be retested every 5 years, and tested again once a system is installed or after a renovation that affects structure or ventilationsource. And a system can be checked at a glance between tests. A U-tube manometer on the pipe indicates that the mitigation system is working, a higher liquid level on one side showing the pressure difference created by the fansource.

A board that knows how many units have systems, when each was installed and when each was last tested has what a planner needs. A board with no results has nothing to plan from. A short reading by the installer follows each installation and gives a first indication. The confirmation that counts is a long-term kit from an independent laboratory, set out and mailed by the unit owner, so that nobody is marking their own work.

What should a board ask before it hires anyone?

Who, by name, will do the measuring and the installing, and what their certification numbers are. Health Canada recommends that the professional hired be certified by the Canadian National Radon Proficiency Programsource. C-NRPP has a public search tool for finding certified professionals and a certification check that confirms an individual's certification from the certification numbersource.

At Calgary Radon Pro the work is done by Plinio Neto, who holds in his own name the C-NRPP Radon Measurement Professional certification (CRT-202965) and the C-NRPP Radon Mitigation Professional certification (CRMT-202966). Any director can look both up in the C-NRPP listing of certified professionals before a motion is put. Further questions for any contractor are collected in our guide to choosing a radon contractor.

Our scope is residential: the units people live in, and not shops, offices or other non-residential space. How a round for many units would be scheduled, what a report to a board would look like and what it would cost have not been published, and this page promises none of them. Describe the complex through the form on this page or on our contact page, and put those questions to us directly. Background on the people involved is on the about page.