X-Message-Number: 2061 Date: Mon, 5 Apr 93 00:50:44 CDT From: Brian Wowk <> Subject: CRYONICS Flooding Risk II I have been further considering the flooding risks associated with a below-ground storage room, and some disturbing thoughts occurred to me. The bottom of a light, foam-insulated room would make an excellent hydraulic piston. If even a small crack in the foundation allowed ground water to seep between the concrete and foam, the foam could be subjected to tons of pressure per square meter. The smallest trickle of water with a head of pressure could push the room right out of the ground! Protective measures: The outer layer of foam insulaton must be bonded to the concrete foundation by a waterproof sealant that adheres well to both concrete and foam. No air spaces must be allowed to exist between the foundation and the foam. Additionally no air spaces above 0'C must be allowed to exist between blocks or layers of foam. That way, if the foundation AND foam ever cracks, water must run into spaces where it will immediately freeze, thereby preventing transmission of hydrostatic pressure. --- Brian Wowk Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=2061