Weatherproofing stuff refers to materials used to protect a structure from the elements. SEALANT is one of the most common weatherproofing materials, and it is a substance used to block air, gas, moisture, dust, and dirt from entering or escaping a structure. SEALANT is typically applied in liquid form and then dries to form a solid barrier. It is often used to fill gaps and cracks in walls, roofs, and other surfaces to prevent water damage.