Radon In Air Mitigation
Here are some methods we use to reduce the level of radon in the air.
SUB-SLAB VENTILATION/ DEPRESSURIZATION SYSTEM
The installation of the sub-slab ventilation system should be in accordance with EPA guidelines. The system’s function is to vacuum up the radon gas and vent it to the outside at the roof level.
Listed below are the major components of the system:
We try to locate the suction point(s) near walls, plumbing stacks, furnace, closets, etc., to ensure unobtrusive installation. The suction point should be located either in the basement floor, crawl space or under slab-on-grade area(s). A 3 inch diameter hole is cut into the floor and a cavity is excavated to reduce the air resistance near the pipe.
- Inserted into the suction point(s) so that the radon and soil gases are drawn into the cavity from airflow channels in the porous soil or aggregate under the slab.
- The hole around the suction point should be sealed with caulk or concrete as necessary.
- The pipe is then neatly routed to the in-line vacuum fan through the unfinished areas of the basement minimizing encroachment into finished areas.
- The diameter of the pipe will be 2 to 4 inches.
- The slope of the pipe should be approximately 1/4 inch per foot to maintain proper drainage of condensate water.
- The radon pipes should be fastened to the structure of the building with hangers or strapping at least every 6 feet on horizontal runs and every 8 feet on vertical runs.
Installed on the exterior of the home should be above the highest eave of the roof, 10 feet or more above ground level, 2 feet above any window or door, and 10 feet from any adjacent building.
- A visual alarm will be installed and signage posted inside and out where the active mitigation system is located. The signage indicates the system function.
- A thermally protected in-line vacuum fan should be mounted vertically with rubber couplings in the attic of the house or garage or outside to assure quiet reliable operation.
- Electrical disconnects (on/off switch) shall be installed within 6’ of the fan.
- A typical sub-slab ventilation system will take 3 to 5 hours to install. Work is usually completed in a single day. However, schedules may require us to complete the job on a second day. Barlow Radon Services will leave the work area clean and dispose of installation debris (excavated aggregate).
SEAL RADON ENTRY ROUTES
- Exposed wall/floor joints and floor cracks that are larger than 1/8" may be caulked. The caulk stops radon gas but does not stop water.
- Diagnostic testing may be used to determine which possible radon entry routes should be caulked.
- Plumbing penetrations and structural columns in the crawl space may be sealed, if necessary.
- The gravel floor of the crawl space should be sealed with a plastic soil gas retarder membrane.
- The membrane should be attached to the inside of the exterior wall with furring strips and sealant.
- The wood furring strips should be attached using concrete nails.
- All seams should be overlapped at least 12 inches and sealed in a permanent air-tight manner.
Note: If the membrane gets torn or damaged, the homeowner is responsible for fixing it. The warranty would be void if these repairs are not made. The homeowner must relocate items stored in the crawl space prior to the start of the work.
- Sump pits that permit entry of radon gas or that would allow conditioned air to be drawn into a sub-slab depressurization system should be covered.
- The sump cover should support up to 155 pounds.
- The cover should be sealed with a latex-based caulk that should allow easy removal of the cover if necessary.
- A view port should be installed which should permit observation of the conditions in the sump pit.
Play it safe and call the experts of Radon in Air Mitigation, Barlow Pump. We're responsive and readily available for a phone call or feel free to submit an inquiry through our contact form.