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Field Test Best Practices: A Resource for Practical Residential Building Science

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Foundations

Buildings communicate with the ground by heat and mass transfer through foundations. Measurement of the hygric and thermal performance of foundations is important in some test homes. It should be coupled with modeling where possible. Typical building simulation programs (EnergyPlus and DOE2, for example) have limited capability at present to model residential foundations in a detailed way, so other tools may be appropriate.

Measuring heat transfer through different portions of a foundation (slab, basement wall, and similar) can be performed with a heat flux transducer. Installation of this sensor is not always easy and can be destructive to house finishings and flooring. Care should be taken to ensure this is minimized.

Moisture flow through foundations requires long-term monitoring, since the overall mass flow rate is typically small. No protocols are known for this measurement. To inspect for a moisture problem, some researchers place a clear plastic liner flat on the concrete or masonry face, and seal it at the edges. Water will become evident between the plastic and concrete since it is not able to evaporate into the air. The relative amount of water collected can be correlated, through experience and judgment, to a moisture problem. It is important to note that concrete is a porous material, so some moisture collection will occur even when it would not be enough create a moisture problem for the home.