"Water resistant" and "waterproof" often refer to penetration of water in its liquid state and possibly under pressure, whereas damp proof refers to resistance to humidity or dampness. Permeation of water vapor through a material or structure is reported as a water vapor transmission rate.
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.
Other than burning down, probably the worst thing that can happen to a residential structure is a foundation problem. The foundation is literally what the house is built on, what keeps the building where it was built, transferring the dead loads and the live loads into the ground.
The source of the vast majority of foundation problems is water. Wet soil beneath a foundation can swell or lose strength.
And that's only the first reason to keep the foundation dry. Then there's the little problem of wet damp basements and crawl spaces that can breed mold and make below-ground interior spaces generally unpleasant. The problem is that typical concrete is not waterproof. Although uncracked (and what concrete is uncracked?) it will typically keep out liquid water, water vapor can still penetrate quite easily. Keeping water drained away from concrete foundations and preventing it from moving through the concrete are essential to a successful structure.
Kansas City Brick & Masonry Repair, In construction, a building or structure is waterproofed with the use of membranes and coatings to protect contents 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.
In building construction, waterproofing is a fundamental aspect of creating a building envelope, which is a controlled environment. The roof covering materials, siding, foundations, and all of the various penetrations through these surfaces need to be water-resistant and sometimes waterproof. Roofing materials are generally designed to be water-resistant and shed water from a sloping roof, but in some conditions, such as ice damming and on flat roofs, the roofing must be waterproof. Many types of waterproof membrane systems are available, including felt paper or tar paper with asphalt or tarto make a built-up roof, other bituminous waterproofing, EPDM rubber, hypalon, polyvinyl chloride, liquid roofing, and more.
Walls are not subjected to standing water, and the water-resistant membranes used as housewraps are designed to be breathable to let moisture escape. Walls also have vapor barriers or air barriers. Damp proofing is another aspect of waterproofing. Masonry walls are built with a damp-proof course to prevent rising damp, and the concrete in foundations needs to be damp-proofed or waterproofed with a liquid coating, basement waterproofing membrane (even under the concrete slab floor where polyethylene sheeting is commonly used), or an additive to the concrete. A potential problem inearth sheltered houses is too much humidity, so waterproofing is critical in these houses. Water seepage can lead to mold growth causing significant damage and air quality issues. Properly waterproofing foundation walls is required to prevent deterioration and seepage.
The penetrations through a building envelope need to be built in a way such that water does not enter the building, such as using flashing and special fittings for pipes, vents, wires, etc. Some caulkings are durable, but many are not a reliable method of waterproofing.
Also, many types of geomembranes are available to control water, gases, or pollution.
Over the past two decades, the construction industry has had technological advances in waterproofing materials, includingintegral waterproofing systems as well as more advanced membrane materials. Integral systems such as hycrete work within the matrix of a concrete structure, giving the concrete itself a waterproof quality. There are two main types of integral waterproofing systems: the hydrophilic and the hydrophobic systems. A hydrophilic system typically uses a crystallization technology that replaces the water in the concrete with insoluble crystals. Various brands available in the market claim similar properties, but not all can react with a wide range of cement hydration by-products and thus require caution. Hydrophobic systems use fatty acids to block pores within the concrete, preventing water passage.
Sometimes the same materials to keep water out of buildings are used to keep water in, such as pond or pool liners.
New membrane materials seek to overcome shortcomings in older methods like PVC and HDPE. Generally, new technology in waterproof membranes relies on polymer-based materials that are extremely adhesive to create a seamless barrier around the outside of a structure.
Waterproofing Kansas City should not be confused with roofing since roofing cannot necessarily withstand hydrostatic head while 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.