1.1 本指南介绍了现有砌块墙体的评估，以确定是否可能增加内部隔热层和连续空气屏障或蒸汽缓凝剂，或墙体热湿管理特性的其他变化。 1.2 本指南描述了评估大规模砌体墙渗水或其他与水分积聚相关问题的原因的方法。本指南不适用于包含通过内部排水、泛水或除墙体储水量以外的其他措施管理大量水的规定的墙体。 1.3 本指南描述了具有所需耐热性和耐蒸汽性的材料的分析、设计和规范，以提高现有大规模砌体墙的能量性能，但这不会给砌体单元或砌体墙内或建筑物内部造成问题。 1.4 本指南适用于实心墙或多层墙，其砌体结构符合本文定义的“大块砌体墙”的要求，且实心砌体的总厚度不小于8英寸。 本指南不适用于设计用于将水作为屏障墙系统或排水墙系统进行管理的砖墙。 1.5 以英寸-磅为单位的数值应视为标准值。括号中给出的值是到国际单位制的数学转换，仅供参考，不被视为标准值。 1.6 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全和健康实践，并确定监管限制的适用性。 ====意义和用途====== 4.1 在现有的和历史上具有重要意义的建筑上，节能问题越来越受到重视，这些建筑采用实心外部大块砌体墙建造。如果没有适当的评估，外墙的热湿特性的变化可能会产生严重的负面影响。 4.2 在添加内部隔热材料、空气屏障、蒸汽缓凝剂或对墙体的耐热性或耐蒸汽性进行其他改变之前，必须彻底了解现有结构、条件、特性、初始含水量以及漏水和漏气的可能性。 4.3 如果以不适当的方式对外墙组件进行改造，则可能会导致现有砌体的退化，以及与湿气相关的问题条件和室内空气质量问题。

1.1 This guide addresses the evaluation of existing mass masonry walls for the potential addition of interior insulation and continuous air barrier or vapor retarder or other changes to the thermal and moisture management properties of the wall. 1.2 This guide describes methods for evaluating causes of water infiltration or other moisture accumulation related problems specific to mass masonry walls. This guide does not apply to walls that include provisions to manage bulk water through internal drainage, flashings, or other measures other than the moisture storage capacity of the wall. 1.3 This guide describes analysis, design, and specification of materials with the required thermal and vapor resistance to improve the energy performance of an existing mass masonry wall, but that would not create problematic conditions to the masonry units or within the masonry wall or interior of the building. 1.4 This guide applies to walls of solid or multiwythe masonry construction meeting the requirements of a “mass masonry wall” as defined herein and having an overall thickness of solid masonry not less than 8 in. This guide does not apply to masonry walls that, by design, are intended to manage water as a barrier wall system or drainage wall system. 1.5 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. ====== Significance And Use ====== 4.1 Energy conservation is being addressed more often on existing and historically significant buildings constructed with solid exterior mass masonry walls. Without proper evaluation, changes to the thermal and moisture properties of the exterior walls could have serious negative impacts. 4.2 A thorough understanding of the existing construction, condition, properties, initial moisture content, and water and air leakage potential are necessary before undertaking the addition of interior insulation, air barrier, vapor retarder, or other changes to thermal or vapor resistance of the wall. 4.3 Degradation of the existing masonry along with moisture related problematic conditions and indoor air quality issues could develop if alterations are undertaken in an improper manner to the exterior wall assembly.