Covers sheathing and underlayment techniques , as well as secrets for installing leakproof valleys .

盖罩和垫层的技术，以及安装防漏山谷秘密。

We want to buy acoustical systems , additives , anti-fracture membranes , sound abatement membranes , underlayment , waterproofing chemicals-additives .

我们要采购听觉的系统，添加剂，反破碎薄膜，声音缓和薄膜，地毯衬。