43. Reduce Radon Levels |
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Most radon-reduction remedies require the skilled services of a
professional contractor who has experience, has completed the U.S.
EPA’s “radon contractor proficiency” course, and
has passed a comprehensive exam in radon mitigation. The following
procedures have been tested successfully on homes with high indoor
radon levels.
Sub-slab suction draws out radon, which accumulates under the concrete
slab, and vents it away from the house.
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Sub-slab
suction is most effective with foundations built on good aggregate
or highly permeable soil. Pumps can be inside the house... |
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...or outside the house. However, in some cases it may be difficult
to create enough suction to prevent radon from penetrating hollow-block
basement walls. |
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Some homeowners drain water away from the foundation of their house
by perforated pipes called footing tiles. If these drain tiles form
a continuous loop around the house and drain into a sump, you can
apply suction to the sump. Drain-tile suction pulls radon from the
surrounding soil and vents it away from the house. |
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A
heat recovery ventilation (HRV) system increases ventilation and uses
the heated or cooled air being exhausted to warm or cool the incoming
air. HRV systems are more effective in reducing radon levels when
used to ventilate only the basement. They are generally not used in
crawl spaces. With HRV, heating and cooling bills will increase. |
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By
covering exposed earth with high-density polyethylene plastic, you
reduce the flow of radon into the house. Exposed earth in basement
cold rooms, storage areas, drain areas, sumps, and crawl spaces is
often a major entry point for radon. But covering exposed earth may
not be enough to solve your radon problems. |
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Sealing
cracks reduces the flow of radon into your home and is often used
with other radon methods. However, by itself sealing has not been
shown to lower radon levels significantly or consistently. It is difficult
to find all of the cracks and gaps in your house. Also, settling and
stresses can create more cracks, so continuing maintenance is necessary. |
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Block-wall ventilation draws radon from the spaces within concrete
block before it can enter the home. It is used most often with sub-slab
suction. Block-wall suction may not work if you cannot seal the top
of the walls, the space between the walls and any exterior veneer,
and openings that could be concealed by masonry fireplaces or chimney. |
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