Homeowners frequently ask us if we put a cover on the top of the radon mitigation piping, and it’s a good question. It does seem like it would be a good idea when you look and see a pipe open to the elements. However, as we will explain in this post, not only is it not necessary for the system to be effective and to protect the fan, pipe covers can actually reduce the effectiveness of the system itself and cause big issues in the winter time.
Lets first go over the main questions we hear from homeowners when they see the opening in the top of the pipe.
Won't rain get into the piping and negatively affect the system?
The radon mitigation fans that we use are designed to handle water coming through the piping, and if water does come down into the pipe when it rains, the water will simply drain back into your drain tile underneath your home to be pumped out again from your sump pump. In our 21 years of business we have never encountered a water issue from rain trickling into our systems piping.
Won’t leaves and other debris get into the piping and wreck the fan or clog the pipe?
The airflow moving through our piping is quite substantial, and it is very rare for debris to find its way into the pipe without getting blown right back out, or getting deterred before it can even get close to going in.
What about animals?
Due to the amount of air flow constantly running through the pipe and how quickly it is exhausting, most, if not all animals stay away from opening to the pipe. In extremely rare cases if an animal does get in, that would be covered under warranty.
Why a cover can be detrimental to your radon system:
Pipe covers can cause your system to freeze over in the winter: When your radon mitigation system is running, it is pulling air from beneath your homes foundation and safely venting it above your roofline. In the wintertime, the outside air is much cooler than the air from underneath your home and this causes condensation to form. With a cover, the condensation starts to build up and freeze over, eventually causing it to freeze over the top of the pipe completely. Once this happens, the radon fan can no longer pull and push any air through and the system becomes useless. This is especially bad because radon levels tend to be higher in the winter time due to closed house conditions, stack effect, and other temperature/pressure differentials. Therefore, with a frozen over system you will start to accumulate high levels of radon in the basement with nothing to extract it out.
Less Airflow: Nearly all covers will affect the amount of airflow running through your radon mitigation piping. To run at peak efficiency and keep your levels as low as possible, the top of the pipe should be left open to allow the most airflow possible.
In conclusion, putting a protective cap on the top of your radon system might sound like a good idea in theory. However, due to the factors discussed above and the fact that it is not necessary, it is something to avoid when installing a radon system in your home.
Brian S. Thompson