Thermal Performance: Part L1A 2013, SAP and Target Fabric Energy Efficiency (TFEE)

Thermal Performance: Part L1A

The 2013 edition of Part L1A (new dwellings) came into force in April 2014. Key changes include a 6% reduction in CO2整个构建组合中的排放,以及一种新的“元素食谱”方法,用于生成合规的住宅规格。亚博会员vip6这为房屋建设者提供了一种直接的,非处方的方式,以实现绩效目标,同时保持合理的设计灵活性。另一个重大的变化是引入织物能效目标,该目标解决了先前版本的L1A部分的限制,该版本允许通过使用可再生和/或低碳技术来抵消相对较低的织物性能标准。


Relatively minor changes have been made to the Standard Assessment Procedure (SAP) in the current 2012 edition. In contrast, there were more significant revisions to the previous version (2009), which were largely in response to the European Energy Performance of Buildings Directive. These revisions improved the tool’s ability to account for year-round fabric performance and included better account of a dwelling’s thermal mass. The changes have also facilitated the new Target Fabric Energy Efficiency standard (TFEE). The TFEE accounts for a dwelling’s combined, annual heating and cooling load measured in kWh/m2, for which a limit is set by SAP based on the performance of a notional dwelling of the same size and shape as that being assed, but with fixed values for the fabric performance e.g. U-values, thermal bridging, air leakage etc. A 15% margin is then added, giving the designer some additional design flexibility.

名义住宅的性能is also used to set the CO2排放目标(TER),但没有余地。下一版L1A的下一版可能会添加到TFEE的保证金,或者可以完全将其删除。总体而言,无需可再生能源即可实现L1A部分的依从性,但是如果使用,则可以稍微放松织物的性能,但仍然可以实现TFEE。

无论在满足L1A部分要求时采用哪种方法,随着我们朝着更高的织物能源效率迈进,混凝土和砖石建设的有益品质变得越来越重要。其中包括可以提供的耐用空气屏障,有助于确保良好的标准气密性is maintained over the building life. In addition, the concrete and masonry sector has developed a broad range of high-performance construction details that are freely available and provide a low-cost means of minimising heat loss from thermal bridging. The level of fabric performance now required by Part L1A makes thermal bridging a key consideration in the overall design; the difference between older construction details and newer, more efficient details can be quite significant in terms of dwelling performance.

Also of importance is the亚搏娱乐网站provided by concrete and masonry, which has a useful role to play as architects and designers tackle the growing problem of summertime overheating in dwellings. The SAP overheating check continues to be the official assessment tool, and remains largely unchanged following the 2010 and 2013 revisions to SAP/Part L1A. However, the Department for Communities and Local Government (DCLG) have indicated that overheating and space cooling are “anticipated for consideration” in the next SAP review. From a concrete and masonry perspective there has been one important revision since the tool was first introduced, which is recognition of night-time ventilation and the added effectiveness it brings to thermal mass as a means of helping to limit or prevent overheating.

More detail on changes to Part L1A, SAP and concrete/masonry homes are included in our publication entitledThermal Performance: Part L1A 2013.