Radon gas mitigation system and kit for a building with a crawlspace

A radon gas mitigation kit for use in a building, wherein the building has an in-ground foundation configured to be supported by ground material and defining a building footprint, wherein the building includes an enclosed structure supported on the foundation, wherein the foundation has a plurality of upstanding walls with bottom ends disposed below a below-grade surface of the ground material within the building footprint and top ends of the walls disposed above a grade-defining surface of the ground material outside the building footprint, wherein the building includes a substantially horizontal floor supported by the foundation adjacent to and at a spaced height above the below-grade surface, wherein the floor forms a crawlspace thereunder and between the foundation walls and the below-grade surface of the ground material, wherein the building further includes a vapor barrier in the crawlspace and arranged in contact with the ground material to form a subterranean environment under the vapor barrier and a substantially enclosed building envelope thereabove, the radon gas mitigation kit comprising:

• a plurality of radon gas intakes arranged to be disposed under the vapor barrier so as to be disposed in the subterranean environment, wherein each radon gas intake is in the form of a length of piping having a tubular peripheral wall and extending between first and second ends, wherein the first and second ends are closed, wherein the peripheral wall has a plurality of openings configured to permit passage of fluid into the piping;
• wherein the radon gas intakes are arranged to be respectively registered with one of the walls of the foundation and are collectively arranged to generally follow the building footprint, and wherein the radon gas intakes are arranged to be in spaced relation to the walls of the foundation;
• a manifold arranged to be disposed above the vapor barrier so as to be within the building envelope, wherein the manifold is arranged to be in fluidic communication with the radon gas intakes;
• a fan arranged to be within the building envelope and in fluidic communication with the manifold, wherein the fan is configured to generate an airflow to draw the radon gas from the subterranean environment and to the manifold;
• and
• an outlet arranged to be disposed in the building at a location thereon above the grade-defining surface of the ground material, wherein the outlet is arranged to be in fluidic communication with the fan and configured to release the radon gas to an outside environment of the building envelope.