位于洗澡间顶部的排气扇上部会连接一个Ø3”的铁皮管,将室内的湿气通过开在屋顶的通气口排出房子。问题之一排气管没有保温,冬季在管内可能形成冷凝水,从而损坏排气扇和屋顶的石膏板。如下图所示。
问题之二,也是更严重的问题,排气管出口没有对准屋顶的出气口,致使大部分湿气直接吹到了屋顶的木板上,水汽聚集在附近的木板,木粱,及下面的保温棉上。图示中部分木板由于受潮损坏已经更换,而木梁也已经受潮变色和开裂。
改进办法就是在Ø3”的铁皮管外面套上一个4“ 的保温软管,安装固定即可。
随附有关规定中的要求
Ontario Building Code 2012,
6.2.3.8. Exhaust Ducts and Outlets
where exhaust ducts containing air from conditioned spaces through or are adjacent to unconditioned spaces, the ducts shall be constructed to prevent condensation from forming inside or outside of the ducts.
9.32.3.10. Ducts
where an exhaust duct passes through or is adjacent to unheated space, the duct shall be insulated to not less than RSI 0.5.