BUILDING MATERIALSWATERPROOFING and DAMPROOFING

DEFINITIONWATERPROOFING A membrane or coating applied to render a surface impervious to water. is the combination of materials used to prevent water intrusion into the structural elements of a building or its finished spaces. Its main purpose is to resist hydrostatic pressure exerted by moisture in the liquid state.DAMPROOFING The treatment of a masonry or concrete surface to retard the absorption of water or penetration of water vaporThe term damproofingis often confused with waterproofing. However,damproofing is a system designed to resist the flow of moisture in a gaseous state i.e. water vapor.

In construction, a building or structure is waterproofed with the use of membranes and coatings to protect contents as well as protecting structural integrity.PURPOSEAREAS THAT NORMALLY REQUIRE WATERPROOFINGWATERPROOFING MATERIALS Waterproofing membranes are made from several one or more layer materials such as: The most important property of the waterproofing material is the material's water absorption rate. A satisfactory rate is below 4% (most materials are between 1-2%). Also important is the thickness of the material.

INTEGRAL SYSTEMWATERPROOFING SYSTEMS- Work within the matrix of a concrete structure, giving the concrete itself a waterproof quality- involves adding materials to the concrete mix to make the concrete itself impermeable-Capillary / Crystalline Waterproofing Can be used as a mortar, sprayed on, or injected. Upon contact, the active chemicals in a capillary coating are "pulled" into the pores of the concrete by capillary action caused by moisture. Once inside, the chemicals react with the free lime in the concrete forming crystals that fill the pores, permanently stopping the transmission of moisture. As long as there is water in the concrete, the active chemicals will continue to penetrate, filling the tiny channels, and sealing out water for good.

CEMENTITIOUS WATERPROOFING Comprise of a mix of dry cement, sand, and liquid latex. The materials are mixed on site resulting in a relatively thin, cementitious liquid that can be applied by brush or roller onto different substrates.

CEMENTITIOUS WATERPROOFING

-SELF ADHERING - MEMBRANEalso known as "peel and stick" membranes, have an integral layer of adhesives, so adhesives do not need to be applied to the surface of membrane at the work site.The release liner is peeled off the adhesive coating and the membrane stuck onto surface at the construction site.TYPES OF WATERPROOFING MEMBRANESFILM or SHEET MEMBRANESheet, self-adhering sheet, sheet metal membrane, and sheet metal waterproofing membranes fall into this category. Film or sheet membrane are attached to a surface using adhesives, mortar, tape, straps, anchors, plastic welding, or fasteners. -Membrane sheets can consists of bentonite clay, modified bitumen, rubber, polyethylene, polypropylene, ethylenepropylenediene monomer (EPDM), reinforced polymers, and other rubber and plastic sheet compositions.MEMBRANE Can be in the form of Sheet or Applied liquid that transforms into a film that is impervious to water when cured.-TORCH-APPLIED SHEET MEMBRANESSheet membrane is torched melting a thin portion of the membrane, thereby attaching it to the surface which is earlier prepared and applied with primer.

SHEET MEMBRANE WATERPROOFINGSELF-ADHERING SHEETNON-ADHESIVE SHEETTORCH - APPLIED

BUILT-UP or LAMINATE MEMBRANEBuilt-up waterproofing membranescan consist of thick viscosity tar, polymer mastics or cementious materials troweled or mopped onto a surface. Reinforcing layers of perforated felt, fiberglass, or fabrics are applied and then additional tar or mastics is layered onto the cloth reinforcement.APPLIED or LIQUID MEMBRANESpray applied membranes, cold-fluid-applied membranes, and hot-applied membranes are types of membranes applied by melting and then fusing a rubber, bitumen, or elastomer layer onto the surface to be waterproofed.Liquid membranes have grown in popularity for horizontal applications.COLD-FLUID-APPLIEDbrushed, rolled, or sprayed onto the surface to be protected. The liquid membrane dries or cures into a permanent waterproof membrane.Eg. Elastomeric Waterproofing, Tank Linings, Acrylic, Epoxy Paint and coatingsHOT-APPLIED SYSTEMSshould include a thermometer so the temperature can be monitored throughout the process.The temperature must be kept within 25 degrees of the required application temperature to ensure even application.

APPLIED or LIQUID MEMBRANEFLUID APPLIED ELASTOMERIC WATERPROOFING SYSTEM

APPLIED or LIQUID MEMBRANEHOT APPLIED WATERPROOFING SYSTEM

INJECTABLE WATERPROOFING- Injectablewaterproofing membranes are used in existing constructions requiring waterproofing improvements. Injectable waterproofing membranes are installed by drilling holesthrough a foundation's floors and walls and then pumping a liquid polyurethane, bentoniteclay, orepoxy waterproofing compound behind the foundation wall or floor to form a positive side waterproofing membrane.

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