Reduce underfloor pressure;
Passive sump systems
Floor type: Solid Floor
To reduce radon with a radon sump, a passive sump system provides a simple means of allowing radon to escape from a cavity under a solid floor.
No fan is fitted in the system to extract radon. The difference in temperature between the bottom and top of the outlet pipe allows air movement out of the building. Passive sump systems can sometimes work, but generally have a limited impact on radon levels, in comparison to active systems (those that use a fan); so be prepared to fit a fan to the system if it does not work very well.