Can You Vent Radon out of a Building?

Venting RadonYes, you can vent radon out of a building. A well-built active radon mitigation system will do the trick – it can push dangerous radon gas out of a building and safely away from breathable air. But there are a few less-than-effective ventilation methods for radon gas that exist, and we’ll tell you why they won’t be saving your lungs any time soon.

Three Things To Know

  1. The Stack Effect: When air in a building heats up, even a little, it rises. That air wants to push out the tiny leaks at the top of the building. The exit of that air causes more air to be sucked into the lower part of the building. This is like putting a vacuum cleaner onto the whole floor of a building. This is called the stack effect, and is a major cause of radon entry. It is a complicated process, and some actions that would seem to be likely to dilute the radon gas (like “venting” radon) can actually increase the stack effect and bring in more radon.
  2. Radon is Heavier Than Air: It’s not a lot heavier, but it is heavy enough that it does not always go where the air is gently flowing.
  3. Concrete is Porous: With enough pressure, soil gasses, including radon, can push through concrete. It can also push through most paints, coatings, and floor coverings.

Radon Venting Approaches You Should NOT Take  

Some people aren’t ready to pay for a fully-functional radon mitigation system, so they seek cheaper alternatives. Radon reduction, however, is one of those fields in which you get what you pay for.

We recommend avoiding the following approaches to radon mitigation.

Installing Roof Vents

Roof vents definitely open buildings to outside air and can come with a number of benefits – but working as an exhaust for radon reduction isn’t one of them.

Stack EffectThe logic contends that because radon is a gas, it will escape to outside air if given the opportunity. But because it is heavier than air, it seldom can get up into the attic. More importantly, you very likely will increase the stack effect and pull in more radon with this type of radon ventilation.

The shelter of a building is an ideal place for a dense, colorless, odorless gas to hang out, and it doesn’t have a reason to pack its bags and leave just because there’s a new way to get out. Save money on installing roof vents for radon ventilation unless you have a different reason to open them up.

Opening Windows

Like roof vents, opening windows is an ill-advised method of radon ventilation.   One would think that if windows are opened, the outside air running through the house would dilute the radon and/or suck it out of one of the windows. Once again, the stack effect and the weight of the gas come into play, and can overpower any dilution effect.

The weight of the gas makes is such that it may not be pulled out of the appropriate windows, and you may mistakenly increase the stack effect, which would cause more suction on the lowest level.

Passive Radon Mitigation

A passive radon mitigation system involves sealing the openings in the lowest level floor and running a pipe from the gravel layer up and through the roof to the outside. It uses natural pressure and air current to vent radon. Mostly, this type of system is installed when a structure is first built, since its chief components run through the building.

However, because of the heavy weight of radon, these systems often do not have enough suction to counteract the pull of the stack effect. Studies have shown that over 70% of the time, a passive system will not be strong enough to bring high radon levels down to acceptable levels.

Sealing Basement Openings

Since most internet information stresses that radon comes into buildings through cracks in the floor and through the sump pit, sealing those would seem as if it would be effective to stop radon.

Most of the time, sealing alone does not work. This is because sealing often causes the soil gas pressure to build up under the floor until the gasses (and radon) actually shove right through the concrete floor.

The Radon Venting Approach You SHOULD Take

An active radon mitigation system is similar to a passive one, except that it uses a fan to actively pull radon from a building and from the ground. It’s the only way to be sure that you’re not only removing radon, but you’re also keeping it from coming back.

Don’t forget that typical ventilation systems (not those for radon) that help circulate other gases from buildings won’t necessarily work for radon. You need specialized care to reach safe levels of radon gas in your building – and you know where to get it. If you’re in Chicagoland and need to get rid of high radon levels, get in touch with the DuPage Radon Contractors team to learn more about your best options for radon removal.

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