Radon Mitigation Paired with Radon Safe Waterproofing System in Manchester, NH

Tuesday, September 30th, 2025 by Marcus Girard

Challenge

Radon gas, often referred to as a “silent killer,” is an odorless, colorless radioactive gas that can pose serious long-term health risks, including lung cancer, when present at elevated levels over extended periods. In New Hampshire, elevated radon levels are especially common due to the region’s granite-rich geology—earning it the nickname “The Granite State.”

In this case, the homeowner’s radon level measured 2.0 pCi/L, which falls within the EPA’s recommended action threshold of 4.0 pCi/L and is considered safe. However, recognizing the potential health implications and seeking peace of mind, the homeowner chose to take a proactive approach by installing a radon mitigation system to further reduce exposure.

These radon concerns were compounded by previous basement water intrusion issues, which had threatened stored belongings and raised the risk of mold development. Seeking a comprehensive solution, the homeowner reached out to Erickson Foundation Solutions, trusted experts in basement waterproofing and indoor air quality—truly the masters of “All Things Basementy.”

Our Customer Care Team promptly scheduled a complimentary home inspection, which was carried out by Peter C., one of our experienced System Design Specialists. During his visit, Peter conducted a comprehensive assessment of the basement, identifying the source of water intrusion, performing radon testing, and taking precise measurements to inform a customized solution.

It was determined that the existing sump pump system was insufficient for managing groundwater seepage, and its design posed a potential risk of allowing radon-laden air to enter the basement from beneath the foundation. In addition to these findings, Peter thoroughly evaluated the space for any other structural or environmental concerns that could impact the homeowner’s safety or property value.

Following this in-depth inspection, Peter proposed a fully integrated solution designed to keep the basement dry, structurally sound, and protected from radon gas, ensuring long-term health and peace of mind for the homeowner. This solution included:

102 feet of WaterGuard with Radon Seal................Perimeter drainage system
16 feet of TrenchLock......................................................Surface drainage system
1 TripleSafe Sump Pump................................................Pumps water out of home
2 IceGuards..........................................................................Frozen discharge line failsafe
60 feet of Exterior Discharge Line...............................Channels water away from home
1 Radon Fan.........................................................................Draws radon gas

Solution

On installation day, our dedicated crew—led by foreman Tyler M.—initiated contact with the homeowner to provide an accurate estimated time of arrival. Upon arriving promptly, Tyler conducted a thorough walkthrough to review the scope of work and align expectations. Before beginning the project, the team took proactive measures to protect the homeowner’s stored belongings in the basement, carefully wrapping valued items in protective plastic to ensure their safety throughout the installation process.

WaterGuard® was strategically installed along the interior perimeter of the basement to effectively capture and redirect groundwater before it could impact the living space. The concrete floor perimeter was carefully excavated to position the drainage system directly atop the footing, optimizing its performance and stability. To enhance drainage and minimize the risk of clogging, the system was surrounded with clean, crushed stone. Prior to finalizing the installation, a flood test was conducted to confirm functionality, after which the system was permanently sealed with concrete for a clean, durable finish.

Our TrenchLock™ surface drainage system was expertly integrated to redirect water around fixed basement infrastructure, such as the oil tank. Engineered to work in tandem with the WaterGuard® perimeter drainage system, TrenchLock forms a continuous channel that efficiently guides water to the sump pump.

Unlike conventional surface drainage solutions—which can inadvertently elevate indoor radon levels by allowing sub-foundation air to enter the basement—TrenchLock is specifically designed to mitigate this risk. Its advanced design permits water entry while preventing air exchange between the foundation and the basement environment, helping preserve indoor air quality in homes where radon exposure is a concern.

TrenchLock™ was also strategically installed at the basement door entrance to intercept and manage potential surface water intrusion originating from the exterior stairwell. This specialized drainage solution is engineered to capture seepage at its point of entry, ensuring water is efficiently channeled into the WaterGuard® system and ultimately directed to the sump pump.

The TripleSafe™ Sump Pump System is engineered to ensure complete and reliable water evacuation from the home. This system features a three-pump configuration: a primary pump for routine water removal, a secondary pump that activates during high-volume water events, and a battery-powered backup pump that provides protection during power outages. This tiered design ensures uninterrupted performance under all conditions, delivering robust, fail-safe flood prevention. In addition to its pumping capabilities, the system includes an airtight sump liner that prevents moisture vapor from escaping into the basement and acts as a barrier against radon gas infiltration from beneath the foundation. By combining redundancy, reliability, and radon mitigation, TripleSafe™ offers superior protection and long-term peace of mind for homeowners.

Water is discharged from the home through a dedicated outlet line, precisely cored through the foundation wall to ensure a secure and efficient exit point. At the exterior, an IceGuard® discharge line protection system was installed to serve as a critical failsafe. In the event of freezing conditions or a blockage, IceGuard’s patented design allows water to escape through engineered openings, preventing pressure buildup and further reducing the risk of basement flooding.

From there, the discharge line is routed to a downward-sloping area away from the foundation, promoting proper drainage and minimizing the chance of water re-entering the structure. To preserve the property’s appearance and protect the line from environmental wear, the discharge pipe is buried underground ensuring both long-term functionality and curb appeal.

To address radon exposure within the home, a radon mitigation system was installed to actively extract radon gas from beneath the foundation. The process began with the creation of a sub-slab depressurization point in the basement floor, serving as the primary extraction site. A sealed PVC vent pipe was securely connected to this point and routed to the exterior of the home, establishing a continuous pathway for radon gas to be safely vented outside. This system effectively reduces indoor radon concentrations by preventing gas accumulation beneath the slab and promoting controlled ventilation—helping maintain healthier indoor air quality.

Once the PVC vent pipe was routed to the exterior of the home, a radon mitigation fan was installed to actively extract radon gas from beneath the foundation slab. This fan creates a continuous negative pressure zone beneath the home, effectively capturing radon and venting it before it can infiltrate the living space.

To ensure safe dispersion of the gas, additional PVC piping was connected to the top of the fan and extended vertically above the roofline, in full compliance with EPA and building code standards. This configuration prevents re-entry of radon into the home and supports proper ventilation.

With the system fully operational, we ensure compliance with EPA and WHO guidelines for indoor radon levels, striving to reduce concentrations to the lowest reasonably achievable levels—promoting a healthier and safer indoor environment for the homeowners.
Upon completion of the project, the installation crew conducted a meticulous cleanup followed by a comprehensive final walkthrough with the homeowner to verify that all work met—if not exceeded—expectations. The homeowner expressed high satisfaction with the results, now benefiting from a fully waterproofed basement and a home protected against radon gas intrusion. This project stands as another example of Erickson Foundation Solutions’ commitment to delivering superior customer service and long-lasting, reliable solutions.