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Radon Mitigation Overview. So, you tell the homeowner that they have elevated radon. Now what do you tell them?. Homes With Radon Concerns Can Be Fixed!. Techniques have been developed to reliably reduce radon to less than 4.0 pCi/L.
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Radon Mitigation Overview So, you tell the homeowner that they have elevated radon. Now what do you tell them? Illinois Department of Nuclear Safety
Homes With Radon Concerns Can Be Fixed! • Techniques have been developed to reliably reduce radon to less than 4.0 pCi/L. • Almost all systems can be installed in one day by a qualified contractor. • The repairs take 24 hours to take effect before retesting can occur • IDNS maintain lists of qualified contractors. Illinois Department of Nuclear Safety
Radon Mitigation • Active Soil Depressurization (ASD) is the most common approach. • Employs a method for creating a vacuum beneath the foundation greater in strength than the vacuum applied to the soil by the building. • Caulking and Sealing is not a stand-alone technique. • Ventilation approaches have proven more costly and less effective. Illinois Department of Nuclear Safety
Mitigation in Illinois • Must be effective at reducing radon • Must be unobtrusive and permanent • Must be quiet • Must be energy efficient • Must have a system function indicator • Primary suction point is independent of sump pit • Sump cover must have an observation port • Must exhaust above the highest eve of the roof. • Membrane must be adhered properly. Illinois Department of Nuclear Safety
Crawl Space System Sub-Membrane Depressurization (SMD) • Vacuum applied beneath plastic. • Radon and moisture collected and exhausted above the highest eave. Illinois Department of Nuclear Safety
Perforated Pipe on Soil • Perforated pipe used to collect gas • Laid on floor of crawl space Illinois Department of Nuclear Safety
Plastic Spread Out in Crawl Space • High density polyethylene laid on dirt. • Edges and seams sealed. Illinois Department of Nuclear Safety
Plastic Sealed to Wall with Caulk Illinois Department of Nuclear Safety
Riser From Plastic • Perforated pipe connected to solid PVC pipe. • Sealed with 2 roof jacks sandwiched together. • Riser routed to fan. Illinois Department of Nuclear Safety
Depressurization Fan • Installed in attic, garage, or outside the living envelope. • Quiet. • Less than 90 watts. • Expected life: 11 years. Illinois Department of Nuclear Safety
System Discharge/Sub-slab depressurization • Discharge should be above highest eave and as close to roof ridge line as possible. • No rain cap. • 1/4 inch screen. Illinois Department of Nuclear Safety
A System Performance Indicator Is Needed Illinois Department of Nuclear Safety
Basement/Slab SystemSub-Slab Depressurization (SSD) Illinois Department of Nuclear Safety
Pipe Connected to Riser • Hole cut through slab. • Pit dug out. • PVC pipe connected to hole. • Pipe routed to suction fan. • Sump pit used only as a secondary suction point. Illinois Department of Nuclear Safety
Caulking Improves Performance • Improves vacuum • Reduces loss of interior air • Polyurethane caulk • Not a stand-alone technique Illinois Department of Nuclear Safety
Fan Floor Use of Perimeter Drain Drain-Tile Depressurization (DTD) • Very cost-effective • System completely outside • Care taken to avoid impacting water collection capability Illinois Department of Nuclear Safety
Foundation Drain System Piping Can Be All Outside • Oversized downspout can be more attractive than pipe. • Outside. • Can be hidden. Illinois Department of Nuclear Safety
1995 CABO - Radon control methods Passive Skeletal Passive and skeletal are not acknowledged mitigation systems. IDNS encourages homeowners to test their home to determine actual radon levels. If homes are above 4pCi/l these systems should be converted to active soil depressurization by a IDNS mitigation professional. NEW CONSTRUCTION Illinois Department of Nuclear Safety
Illinois New ConstructionPassive • Passive new construction systems rely solely on the convective flow of air upward in the vent pipe for sub-slab depressurization. The system consists of a vertical vent pipe routed through conditioned space from the suction pit to 12 inches above the roof . Illinois Department of Nuclear Safety
Illinois New ConstructionSkeletal • A skeletal system is a system that is designed for the installation of a vent fan and may consist of multiple vent pipes. This includes vertical and angled runs that are not necessarily routed through living space that may be joined to a single termination above the roof or may terminated separately above the roof. EXHAUST Illinois Department of Nuclear Safety
Key Elements of ASD SystemsU.S. EPA Radon Mitigation Standards • Discharge points should be 10 feet above ground and 10 feet from any building opening that is on a plane 2 feet below exhaust. • Sealing concrete cracks, plastic in a sub-membrane, and open block tops; reduces operating costs, improves radon reduction, and minimizes potential for back draft of combustion appliances. • Proper system operation indicators and operation manual to be part of installation. Illinois Department of Nuclear Safety
For Sale SOLD Radon Does Not Have To Be A Problem Nor A Deal Breaker Illinois Department of Nuclear Safety