info on exterior insulation/filling material, etc.-1999

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Report A3132.1 Page 9 No diumal effects can be seen at the two lower depths. The temperatures at the lowest depth approximates a sine wave each year. It should be noted that in both winters, the frost penetrated approximately 150 mm. The frost depth temporarily reached 270 mm in the second winter (not shown in graph). Deep snow cover, and repeated thaws in both heating seasons may be the cause of shallow frost penetration. An independent temperature measurement in the second winter, 10 m from the house showed the same result. This indicates that there is an undetectable effect because of basement heat loss on the soil temperature at 2 m from the house. Soil Moisture Content A single TDR probe (time domain reflectometry) was deployed about 2 m from the east wall, and 1 m down into the ground, to monitor soil moisture content on an ongoing basis. Figure 8 presents the results of the soil moisture content monitoring over the period from October 1996 to June 1998. It shows that the soil was wet throughout the first heating season and dried substantially in the summer of 1997. Throughout most of the second heating season, the soil stayed dryer than the first, until the spring thaw in 1998. Temperature Profiles Through the Wall at Mid-Height Figure 9 shows the two-year temperature record at four locations through the wall at specimen W2: the interior surface, both sides of the concrete, and the exterior surface of the specimen in,contact with the soil. The inner surface of the wall is kept near 21°C, with small variations throughout the two years. Main control events such as power outages and changes from heating to air conditioning and back are evident from these temperature readings. The temperature at both sides of the concrete are quite close to one another (concrete being a poor thermal insulator), and these vary from 15°C to 20°C, from winter to summer. The lowest curve in the graph is the temperature record for the insulation/soil interface. These vary between about 5°C in winter up to a maximum of about 20°C in summer. The periodic 'spikes' in this curve correspondYorded events of heavy precipitation or winter thaws. The August 8, 1996 rain was a 1 in 75 year event for Ottawa, which caused local flooding around the test hut.. During this storm, the temperature at the insulation/soil interface deflected upwards, apparently due to warm rainwater moving down the wall. Such deflections were observed at the mid, low and bottom thermocouple positions during the same period, tracing the path of the water. These deflections were much less noticeable at the high position, where the soil temperature would be closer to the temperature of the moving water. L