如屋顶防水，直接做在屋顶表面，墙壁防水应直接做在外墙、水箱漏水直接做在水箱内层，水有压 力会往他处扩散，房子里死角的地方也不容易施工。这里所讲的“优于”是相对比较的，而非绝对性的 。因为随着科技的发达，市面上陆续有人推出背水面施工的防水材料以铜钟 一次性止血带 标志桩模具 钢丝轮 流水槽模具 防撞墙模具 检查井钢模具 不锈钢铸件 模锻件及高低压注入合成树脂产生膨胀 结晶体，亦可防水，但是并非所有的场合都可成功的施工，所以非不得已，应该采正面防水施工。
If roof waterproofing is done directly on the roof surface, wall waterproofing should be done directly on the outer wall, water tank leakage should be done directly on the inner layer of the water tank, water pressure will spread to other places, the dead corner of the house is not easy to construct. The "superiority" mentioned here is comparative rather than absolute. With the development of science and technology, water-proof materials for backwater construction and expansive crystals produced by high-pressure and low-pressure injection of synthetic resins are introduced in succession on the market, which can also be waterproof. But not all occasions can be successfully constructed. Therefore, frontal waterproof construction should be adopted