Research on Advanced Technologies for Housing: Eave Icing of Residential Buildings

拟开展的工作是针对全国低层住宅存量屋檐结冰的多学科研究项目。具体地说，该项目的目标是对屋檐结冰有一个基本的了解，而目标是开发一个分析模型，预测一个和两个家庭住宅单元屋檐上的冰坝的大小。不幸的是，屋檐冰坝的形成在较冷的气候中很常见。当冰坝变得很大时，内表面(墙壁和天花板)被弄湿是典型的结果。屋檐结冰可以说是美国一户和两户家庭中与冰雪相关的最常见和最昂贵的损失。从本质上讲，将要开发的模型将研究屋檐上坡融水的产生以及屋檐区域融水的凝固。这种分析模型的发展将使工程师和建筑商能够有知识地和定量地处理问题。也就是说，对于给定的屋顶(即固定的屋脊到屋檐的距离、屋顶坡度、屋顶R值等)，分析模型将允许计算导致冰坝形成的冰冻天数和屋顶积雪深度的组合。相反，对于给定的冬季环境和屋顶，该模型允许计算避免室内潮湿所需的最小屋檐悬挑距离或连续金属闪光的宽度。该模型将通过在全尺寸建筑物上进行简单的现场实验观察来验证和确定基准，并尽可能通过比较和分析以前冬天的保险公司损失信息来进行验证和确定基准。该项目的目标与推进住房技术伙伴关系(PATH)的目标是一致的。也就是说，如果使用得当，这些成果将减少财产破坏的风险，提高耐用性，降低维护成本，从长远来看，还将降低住房的每月成本。多学科项目团队由伦斯勒大学的迈克尔·奥鲁尔克教授领导，他是积雪对建筑结构影响领域的专家。合作者是伦斯勒机械工程系的理查德·史密斯教授，他是传热学和凝固方面的专家。为了确保这项新技术的适当转让和使用，成立了一个由全国住宅建筑商协会和州立农场建筑技术研究实验室代表组成的项目咨询小组。

The proposed work is a multi-disciplinary research project on eave icing of the nation's low-rise residential building stock. Specifically the goal of the project is to develop a fundamental understanding of eave icing while the objective is development of an analytical model which predicts the size of a ice dam at the eave of one and two family dwelling units. The formation of eave ice dams is, unfortunately, a common occurrence in colder climates. When ice dams become large, wetting of interior surfaces (walls and ceilings) is the typical result. Eave icing is arguably the most common and costly ice and snow related loss for one and two family dwelling units in the United States. By its nature, the model to be developed will address both the generation of meltwater upslope of the eave, as well as solidification of the meltwater at the eave area. This development of an analytical model will allow engineers and builders to deal knowledgeably and quantitatively with the problem. That is, for a given roof (i.e., fixed ridge to eave distance, roof slop, roof R-value, etc) the analytical model would allow one to calculate the combination of below freezing days and roof snow deph which result in ice dam formation. Conversely, for a given winter environment and roof, the model allows one to calculate the minimum eave overhang distance or width of continuous metal flashing required to avoid interior wetting. The model will be verified and benchmarked through simple in-situ experimental observations on full scale buildings and to the extent possible by comparison to and analysis of insurance company loss information from prior winters. The project's objectives are compatible with those of the Partnership for Advancing Technology in Housing (PATH). That is, the results, when properly used, will lead to a reduced risk of property destruction, improved durability, reduced maintenance costs and in the long run reduced monthly cost of housing.The multi-disciplinary project team is lead by a civil engineer, Professor Michael O'Rourke of Rensselaer, who is an expert in the area of snow effects on building structures. The Co-PI is Professor Richard Smith, of Rensselaer's Mechancial Engineering Department, who is an expert on heat transfer and solidification. In order to ensure appropriate transfer and use of this new technology, a project advisory group consisting of representation from the National Association of Home Builders and State Farm's Building Technology Research Lab has been established.