ABSTRACT It is estimated that around 80% of UK dwellings have uninsulated ground floors, representing a significant heat loss mechanism in these buildings. In this research, an aggregated assessment of dwelling heat loss was made using the electric coheating test before and after a ground floor retrofit took place. Heat loss was reduced by 24% (43 ± 18 W/K) indicating that suspended timber ground floor retrofits could improve thermal comfort for occupants and contribute to government domestic energy efficiency policy targets. The findings indicate that disaggregated evaluation methods, such as spot heat flux density measurements, may overestimate the benefits of fabric retrofits. Aggregate methods may therefore be more appropriate tools with which to evaluate retrofits. The U-value improvement resulting from the suspended timber ground floor insulation retrofit, derived via aggregate measurement, was 0.55 W/m²K. Disaggregated spot heat flux density measurements indicated the improvement was 0.89 W/m2K. This research also indicates that Energy Performance Certificates, are unlikely to provide a reliable estimate of energy savings, because they rely on default assumptions for fabric U-Values and ventilation rates. This has implications for policy evaluations as well as householders, who may be excluded from financial support for retrofits.

中文翻译：

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改造悬浮木材底层；比较汇总和分解的评价方法

摘要 据估计，大约 80% 的英国住宅具有未隔热的底层，这代表了这些建筑物中重要的热损失机制。在这项研究中，在底层改造之前和之后，使用电加热测试对住宅热损失进行了综合评估。热损失减少了 24% (43 ± 18 W/K)，这表明悬浮木材底层改造可以提高居住者的热舒适度，并有助于实现政府国内能效政策目标。研究结果表明，分散的评估方法，例如现场热通量密度测量，可能会高估织物改造的好处。因此，综合方法可能是更合适的评估改造的工具。通过骨料测量得出的悬浮木材底层绝缘改造导致的 U 值改进为 0.55 W/m²K。分解的现场热通量密度测量表明改进为 0.89 W/m2K。这项研究还表明，能源性能证书不太可能提供对节能的可靠估计，因为它们依赖于织物 U 值和通风率的默认假设。这对政策评估和住户都有影响，他们可能被排除在对改造的财政支持之外。不太可能提供节能的可靠估计，因为它们依赖于织物 U 值和通风率的默认假设。这对政策评估和住户都有影响，他们可能被排除在对改造的财政支持之外。不太可能提供节能的可靠估计，因为它们依赖于织物 U 值和通风率的默认假设。这对政策评估和住户都有影响，他们可能被排除在对改造的财政支持之外。