Does the vent pipe need to go all the way to the roof? Is it good enough to have it capped tightly and labeled?The project plans to use the following strategy for radon mitigation:The sub slab meets the requirements of radon resistant construction, including a 6mm plastic lining, a gas permeable layer and a sealed foundation. The vent pipe is capped tightly and labeled, but it does not go all the way through the roof. We could have taken the pipe through the roof if needed but didn\'t want to put more holes than needed in the roof, especially with a 10 kW solar up and under-roof solar thermal to deal with. I don\'t think a normal builder would want to do this until tests showed that radon was a problem either. We had Mid-Atlantic Associates, a third-party environmental consultant, perform indoor air quality samples to test for radon, among other pollutants. Tests showed that radon were well below levels of concern. These are attached.