<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Hi, Clark--<div><br></div><div>Radon gas cannot go through solid material, it must be transported in air, so whatever will form a tight air seal will block off radon.<br><div><br class="webkit-block-placeholder"></div><div>Mike O'Brien</div><div apple-content-edited="true"><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; font-size: medium; "><div><br></div></span><br class="Apple-interchange-newline">
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<br><div><div>On Apr 2, 2012, at 2:22 PM, Clarke Olsen wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div><br>A ground floor room tests positive for Radon - not high, but more then nothing.<br>The floor is 4+" of concrete on 2" ext. styrofoam, on 6 - 8" of gravel.<br>Big (1/2") joint between foundation and slab is the likely source.<br>Should I: <br> a) seal-up the joint with non-shrinking mortar?<br> b) seal it with expanding foam? With caulk?<br> c) arrange some form of fat baseboard vent?<br><br>Clarke Olsen<br>373 route 203<br>Spencertown, NY 12165 <br>USA<br>518-392-4640<br><a href="mailto:colsen@fairpoint.net">colsen@fairpoint.net</a><br><br><br><br><br><br>_______________________________________________<br>Greenbuilding mailing list<br>to Send a Message to the list, use the email address<br>Greenbuilding@bioenergylists.org<br><br>to UNSUBSCRIBE or Change your List Settings use the web page<br>http://lists.bioenergylists.org/mailman/listinfo/greenbuilding_lists.bioenergylists.org<br><br></div></blockquote></div><br></div></body></html>