Field Testing of an Unvented Roof with Fibrous Insulation, Tiles, and Vapor Diffusion Venting

Ueno, K.¹  Lstiburek, J. W.¹ 

[1] Building Science Corporation, Westford, MA (United States)

关键词: residential;    residential buildings;    BSC;    Building Science Corporation;    Building America;    unvented roof;    cathedralized roof;    hot-humid;    tile roof;    diffusion vent;    moisture risks;    moisture damage;   

DOI  :  10.2172/1239735
RP-ID  :  DOE/GO--102016-4764
PID  :  OSTI ID: 1239735
Others  :  Other: 7316

学科分类：能源（综合）

美国|英语

来源: SciTech Connect

【 摘 要 】

This research is a test implementation of an unvented tile roof assembly in a hot-humid climate (Orlando, FL; Zone 2A), insulated with air permeable insulation (netted and blown fiberglass). Given the localized moisture accumulation and failures seen in previous unvented roof field work, it was theorized that a 'diffusion vent' (water vapor open, but air barrier 'closed') at the highest points in the roof assembly might allow for the wintertime release of moisture, to safe levels. The 'diffusion vent' is an open slot at the ridge and hips, covered with a water-resistant but vapor open (500+ perm) air barrier membrane. As a control comparison, one portion of the roof was constructed as a typical unvented roof (self-adhered membrane at ridge). The data collected to date indicate that the diffusion vent roof shows greater moisture safety than the conventional, unvented roof design.