8 DIY Radon Mitigation Mistakes

Radon mitigation is an important part of the many steps to protect against this silent killer. The EPA recommends solving the problem before it reaches a level where it’s too dangerous to ignore or repair. However, people still make mistakes when deciding how to fix radon issues in their homes.

Many people choose to install the radon mitigation system on their own. This can save over $1000 in installation costs. While it is entirely possible to install a system oneself, many common mistakes can happen.

If you are considering installing a radon mitigation system by yourself, then this article is for you. We will look at some of the common mistakes that DIYers often make, so be aware of them before you start.

Here are those DIY mitigation mistakes you should be aware of;

Installing the fan in the basement or crawl space

As per the EPA guidelines, one should not install a radon mitigation fan in or below living spaces. It should not be installed in a conditioned space either. However, many DIY installers are unaware of this. They install the fan in their basement, which in their opinion, is away from corroding elements like water and sunlight and away from sight. While this logic is correct, one should not ignore the EPA guideline. (Source, page 12)

The reason for this guideline is that any leaks or cracks in the vent pipes can leak high concentrations of radon into your home. Radon fans typically pull 100 to 250 CFM of air from the soil underneath the basement. Because of this high suction force, any cracks in the pipes can let a lot of radon pass through. In addition, the radon concentration of the air in the radon system is hundreds of picocuries per liter. Leaking this air into the house’s living areas poses a much higher risk than it did before installing the mitigation system.

A radon mitigation system with the fan installed in the basement will also fail home inspection when selling the home, as this is a clear violation of the EPA code.

Therefore, the radon fan must be installed outside or in the attic or garage. This allows the highly concentrated radon air to mitigate outside if any cracks or leaks occur. Besides, radon fans are better at pulling the air than pushing it, so it is recommended to install them as far away from the basement as possible.

Using thin, low-quality pipes

Radon pipes are made of PVC or ABS. EPA mandates that the pipes used should be schedule 40. But many people try to cut corners by using Schedule 20 PVC pipes. These pipes are thinner, and they cost only half as much. I wonder where they find this pipe because if you ever went to a local store or searched online, you won’t find it. They won’t pass any code, and if you ask a plumber, they will say ‘don’t buy that junk’.

But unfortunately, many DIYers and some mitigation contractors use these thin pipes for the radon mitigation system. While this may save you some money, it can cause some serious problems down the road. These thin pipes crack easily, and they deteriorate when exposed to sunlight. They are also hard to be sealed. All these can cause the radon gas to seep back into your home. So avoid doing this at all costs.

This shortcut to cost reduction usually happens when houses are sold. When the seller finds out that his house has high radon levels, he tries to install a cheap mitigation system. This will save him some money, but it is unfortunate for the buyer. So if you are buying a house with a newly installed mitigation system, make sure that the system is of high quality.

Incorrectly sizing the system

To be honest, it is difficult for even a mitigation contractor to size a radon fan correctly, so I will be amazed if a DIYer does it any better. The size required for the radon fan depends on the size of the house, the radon levels, and the soil conditions. Usually, a 3 inch or a 4-inch pipe is used to vent the gas. However, the size of the radon fan varies from 100 to 450 CFMs. So, for a DIYer, it is hard to estimate the fan size correctly.

It is alright to have a fan that is more powerful than that is needed. However, many DIYers also install smaller fans than necessary, which fail to reduce radon levels to safe values. It is easy to replace one fan with another, but the problem here is that most companies do not accept returns if you DIY. So, in the end, you will have to buy another fan.

Inadequate sealing

The radon mitigation system needs to be sealed properly to prevent any leaks and such. The radon fan is powerful enough to cause the seals to break off if they are not done properly. The fan is attached to the pipes using heavy-duty rubber couplings. Some DIYers attempt to glue them together, which is a terrible idea. The glue will not last for more than a few days, and after that, the pipe will begin to leak. So, when installing the radon fan, be extra careful.

Many also forget to seal the suction pit of the radon system properly. A suction pit is a hole in the basement of your home where the inlet of the radon pipe goes into. One should seal the space between the radon pipe and the pit properly to prevent radon from leaking into the basement. If you have a sump pump, it should be sealed too.

Adding a rain cap on the vent pipe

One shouldn’t add a rain cap on the exhaust pipe of the radon mitigation system. A rain cap will hinder the free flow of air, and they also direct the gases downwards, which is against EPA guidelines. In fact, the airflow in a radon pipe is so strong that it will prevent any water from entering it. This also deters any rodents and insects.

If you are afraid that rainwater may enter the vent pipe, you can install it horizontally but away from the house. This will keep the water away, and it is not against the code either (Source).

A rain cap is advised only if you are using a passive mitigation system. This system doesn’t use a radon fan but instead uses the air pressure differences and currents to drive radon out of the house. However, this system is installed during the construction of the house, so there is no scope for DIYers here.

It is also important to seal the floor using a vapor barrier if you have an unfinished basement or a crawl space. The vapor barrier prevents any radon from entering the house, and it acts as a wall to create the negative pressure zone needed for the mitigation system to work.

Inadequate height of the vent pipe

EPA mandates that the vent pipe should be at least 1 foot above the roof ridge. It should also be at least 10 feet away from windows and other openings with access to the home’s living areas (Source, Page 35). This is to ensure that radon doesn’t re-enter your home.

However, these guidelines are difficult to be put into practice. So most DIYers end up having the exhaust close to a window. This can cause the radon gas to re-enter the house and increase the levels to more than before.

Improper installation of the vent pipes

The vent pipes of a radon system should be pitched to the ground. This is because the air in the soil and the basement is usually humid. And condensation can occur in the radon pipes when this humid air passes through them. When the condensation occurs, the water should drain back into the ground.

It is also important to avoid any bends in the pipings. But more often than not, there will be bends, and the pitch of the horizontal parts of the piping goes wrong. This will cause the condensed water to get trapped in the pipes creating a loud gurgling noise when the fan runs.

Some DIYers also install traps in the piping, which can flood the fan. So if you are installing mitigation by yourself, make sure the pipes are installed correctly. If you live in cold climate areas, wrapping the ducting with thermal insulation will help to reduce condensation. The insulations will keep the ducts warm, and so the water content in them will be vented along with the radon air.

Installing the fan horizontally or at an angle

Another common mistake DIYers do is installing the radon fan horizontally or at an angle. This will cause water to be trapped in the fan. Also, the bearings of the fan are not designed to work at an angle or horizontally. So installations like this will lead to the premature death of the fan in addition to making the system less efficient.

So, DIYers should install the radon fan vertically. Avoid bends in the pipes as much as possible. Install the fan outside, away from living areas. Also, vent the pipes correctly.

Charles John

A novice DIYer who learns about home ventilation. I am a mechanical engineer and have a basic knowledge of HVAC systems but I learn continuously to make myself the best blogger in that space.

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