Watertight

Watertight

Waterproof or water-resistant describes objects relatively unaffected by water or resisting the ingress of water under specified conditions. Such items may be used in wet environments or under water to specified depths. Waterproofing describes making an object waterproof or water-resistant (such as a camera, watch or mobile phone).

"Water resistant" and "waterproof" often refer to penetration of liquid water. Permeation of water vapor is reported as a water vapor transmission rate. Also, water from condensation is usually separate from "water resistant".

The hulls of boats and ships were once waterproofed by applying tar or pitch. Modern items may be waterproofed by applying water-repellent coatings or by sealing seams with gaskets or O-rings.

In construction, a building or structure is waterproofed with the use of membranes and coatings to protect contents underneath or within as well as protecting structural integrity. The waterproofing of the building envelope in construction specifications is listed under '07 - Thermal and Moisture Protection' within MasterFormat 2004, by the Construction Specifications Institute, and includes roofing material as well as waterproofing materials.

Waterproofing is used in reference to building structures (basements, decks, wet areas, etc.), watercraft, canvas, clothing (raincoat, waders) and paper (e.g., milk and juice cartons).

Waterproofing should not be confused with roofing, as roofing cannot necessarily withstand hydrostatic head, and waterproofing can.

The standards for waterproofing bathrooms in domestic construction have improved over the years, due in large part to the general tightening of building codes.