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Glossary of Terms

  • ABRASION RESISTANCE.  Resistance to wear resulting from mechanical action on a surface.

  • ABOVE GRADE. The portion of a building that is above ground level.

  • ACCELERATED AGEING. A set of laboratory conditions designed to produce in a short time the results of normal aging. Usual factors included are temperature, light, oxygen and water.

  • ACCELERATED WEATHERING. A set of laboratory conditions to simulate in a short time the effects of natural weathering.

  • ACCELERATOR.  An ingredient used in small amounts to speed up the reaction time of a product.

  • ACETONE. Dimethyl Ketone. A very volatile solvent. Particularly useful for cleaning metal substrates.

  • ADHERED.  A body which is held to another body by an adhesive.

  • ADHESION. The clinging or sticking together of two surfaces. The state in which two surfaces are held together by forces at the interface.

  • ADHESION.  Mechanical. Adhesion due to the physical interlocking of the adhesive with the surface irregularities of the substrate.

  • ADHESIVE. A substance capable of holding materials together by surface attachment.

  • ADHESIVE FAILURE. Type of failure characterized by pulling the adhesive or sealant loose from the surface to which it is applied

  • ADHESIVE STRENGTH.  The ability of sealants to bond to a particular substrate, including adhesion during substrate movement.

  • ABSORPTION. The action of a body in condensing and holding gases and other materials at its surface.

  • AGEING. The progressive change in the chemical and physical properties of a sealant or adhesive.

  • AMBIENT TEMPERATURE. Temperature of the air surrounding the object under construction.

  • BACKING ROD. A compressible material used at the base of a joint opening to provide the proper shape factor in a sealant.

  • BEAD. An applied sealant in a joint irrespective of the method of application, such as caulking bead, glazing bead, etc.

  • BELOW GRADE. The portion of a building that is below ground level.

  • BILSTER. An enclosed raised spot evident on a membrane or other coating after it has been applied. They are mainly caused by the expansion of trapped air, water vapour, moisture or other gases.

  • BITUMINOUS EMULSION. (1) A suspension of minute globules of bituminous material in water or in an aqueous solution; (2) A suspension of minute globules of water or of an aqueous solution in a liquid bituminous material (invert emulsion).

  • BOND (noun). The attachment at an interface between substrate and adhesive, or sealant.

  • BOND (verb).  To join materials together using an adhesive.

  • BOND FACE. The part or surface of a building component which serves as a substrate for an adhesive or sealant.

  • BOND BREAKER.  A layer or coating that is applied to a specific area of a substrate, such that, when a subsequent layer or coating is applied over the bond breaker, it will not bond or adhere in that area.

  • BOND STRENGTH.  The force per unit area necessary to rupture a bond.

  • BUTT JOINT. A joint in which the structural units are joined to place the adhesive or sealant into tension or compression.

  • BUTYL RUBBER. A copolymer of isobutene and isoprene. As a sealant it has low recovery and slow cure, but good tensile strength and elongation.

  • CAP SHEET. A granule-surfaced, coated felt used as the top ply of a built-up roofing membrane.

  • CARBON BLACK.  Finely divided carbon formed by the incomplete combustion of natural gas.

  • CATALYST. Substance added in small quantities to promote a reaction, while remaining unchanged itself.

  • CAULK (noun). A sealant with a relatively low movement capability.

  • CAULK   (verb). To fill the joints in a building with a sealant.

  • CELLULAR MATERIAL.  A material containing many small cells dispersed throughout the material. The cells may be either open or closed.

  • COHESION. The molecular attraction which  holds the body of a sealant or adhesive together. The internal strength of an adhesive or sealant.

  • COHESIVE FAILURE. The failure characterized by pulling the body of the sealant or adhesive apart.

  • COLD JOINT.  A plane of weakness in concrete caused by an interruption or delay in the pouring operation, permitting the first batch to start setting before the next batch is added, with the result that the two batches have little or no bond.

  • COLLAR. Pre formed flange placed over a penetration or vent pipe to seal the area around the penetration.

  • COMPRESSION SEAL. A preformed seal which is installed by being compressed and inserted.

  • COMPRESSION SET. The amount of permanent set that remains in a specimen after removal of a compressive load.

  • COMPRESSIVE STRENGTH. The useful compressive strength of grout is proportional to the grout depth and the foundation strength (AS2073.4).

  • CONDENSATION. The change of water from vapour to liquid when warm, moisture-laden air comes in contact with a cold surface.

  • CONE PENETROMETER. An instrument for measuring the relative hardness of soft, deformable materials.

  • CONSTRUCTION JOINT.  A butted joint formed in a structural slab in order to end one pour and start another at a later time.

  • CRACK. A non- Linear separation or fracture occurring in a material. May be generally caused by induced stress, dimensional instability or substrate movement.

  • CRAZING. A series of fine cracks which may extend through the body of a layer of sealant or adhesive.

  • CREEP. The deformation of a body with time under constant load.

  • CROSS LINKED. Molecules that are joined side by side as well as end to end.

  • CURE. To set up or harden by means of a chemical reaction.

  • CURE TIME. Time required affecting a complete cure at a given temperature.

  • CURING AGENT. A chemical which is added to affect a cure in a polymer.

  • DELAMINATION. Separation of the laminated layers of a component or system.

  • DEPOLYMERISATION. Separation of a complex molecule into simpler molecules.

  • EFFECTIVE BEARING AREA (EBA). That area of grout in contact with the underside of base plate.

  • ELASTICITY. The ability of a material to return to its original shape after removal of a load.

  • ELASTOMER. A rubber material, which returns to approximately its original dimensions in a short time after a relatively large amount of deformations.

  • ELONGATION. The ability of a material to be stretched by the application of a force.

  • EPDM. Ethylene Propylene Diene Monomer. A single ply membrane consisting of synthetic rubber. Application can be ballasted, fully adhered or mechanically attached.

  • EPS Board. Expanded polystyrene. A very light-weight insulation roofing material with a foam structure.

  • EXOTHERMIC. A chemical reaction which gives off heat.

  • EXPANSION. Expansion (or shrinkage compensation) additives are used to overcome both plastic shrinkage and drying shrinkage. Expansion of the grout whilst it is in the plastic state before curing.

  • EXPANSION DUAL PHASE. Type C grouts have dual expansive systems, in that they expand in the plastic state and do not shrink in the hardened state.

  • EXPANSION - FREE. Grouts which are allowed to expand freely with no restraint.

  • EXPANSION - GASEOUS. Gaseous expansion of mortars can occur in the plastic state and increase the volume of the grout by up to 4%.

  • EXPANSION HARDENED STATE. In the hardened state it is the generation of some form of internal stressing to compensate for drying shrinkage stresses.

  • EXPANSION JOINT. A structural separation between two building elements that allows free movement between the elements without damage to the roofing or waterproofing system.

  • EXTENDER. An organic material used to increase the volume and lower the cost of a sealant, adhesive or grout.

  • EXTENSIBILITY. The ability of a sealant to stretch under tensile load.

  • EXTRUSION FAILURE. Failure of a material due to rapid cyclic deformation

  • FABRIC. A woven cloth or material of organic or inorganic filaments, threads or yarns used for reinforcement in certain applications.

  • FIELD MOULDED SEALANT. A mastic sealant which takes its shape by being placed into the joint.

  • FINAL SET. In accordance with AS1012.18, final set is reached when the grout attains a specified reading on the Vicat apparatus.

  • FLASH POINT. The critical temperature at which a material will ignite.

  • FLASHING. Strips, usually of sheet metal, to waterproof the junctions of building surfaces, such as roof peaks and valleys, and the junction of a roof and chimney. Also used to terminate waterproofing membranes.

  • FLUIDITY. Fluidity of grout is tested to CRD C611 (flow cone) or ASTM C230 (flow table), and relates to its flow characteristics.

  • GASKET. A deformable material placed between two surfaces to seal the union between the surfaces.

  • GRANULES. Ceramic coated coloured crushed rock that is applied to the exposed surface of asphalt based roofing products.

  • HARDENER. A substance added to control the reaction of a curing agent in a sealant or adhesive.

  • HARDNESS. The resistance of a material to indentation. On the shore A scale, hardness is measured in relative numbers from 0 to 100.

  • HEADER BOX. Part of the formwork located above the finished grout height to allow for a continuous pour of grout with no air pockets.

  • HEAD OF GROUT. It is the head pressure formed in the header box by the grout not yet under the base plate that ensures continuous flow.

  • HEAT OF HYDRATION. The exothermic (heating) reaction of the cement caused by the hydration process.

  • HYDROSTATIC PRESSURE. Pressure applied to envelope materials by various heights of water at rest.

  • HYPEALON. A registered trademark of E.I. DuPont inc. for a rubber roofing product, “chlorosulfonated polyethylene”

  • ISO Board. Polyisocyanurate polyurethane foam supplied in a board form primarily as an insulation material for the construction industry.

  • INTERFACE. The common boundary surface between two substances.

  • INITIAL SET. In accordance with AS1012.18, initial set is reached when the grout attains a specified reading on the Vicat apparatus.

  • JOINT (adhesive use). The point at which two substrates are joined by an adhesive.

  • JOINT (sealant use). The opening between component parts of a structure.

  • LAITANCE. A weak coating which commonly forms on the surface of concrete caused by bleeding water to the top of over wet concrete. Laitance may be detected by scraping the concrete surface with a putty knife, if a quantity of loose powdery material is observed or easily removed, excessive laitance may be considered to be present.

  • LAP JOINT. A joint in  which  the  component  parts overlap so that the sealant or adhesive is placed into shear action.

  • LEED. A green building rating system that stands for “Leadership in Energy and Environmental Design”. LEED is the nationally accepted standard in the UK for the design, construction and operation of high performance green buildings. LEED recognizes performance in five key areas: sustainable site development, energy efficiency, materials selection, indoor environmental quality and water savings.

  • LIQUID APPLIED MEMBANE. Generally applied to cast-in-place concrete surfaces in one or more coats to provide fully-adhered waterproof membranes which conform to all contours.

  • LOOSE-LAID MEMBRANES. Membranes that are not attached to the substrate except at the perimeter and at penetrations. Typically, loose-laid membranes are held in place with ballast, such as water worn stone, gravel pavers, etc.

  • MASTIC. A thick, pasty sealant or adhesive.

  • MECHANICALLY-FASTENED MEMBRANES. Generally   used to describe membranes that have been attached at defined intervals to the substrate mechanically.

  • MODIFIED BITUMEN. (1) a bitumen modified through the inclusion of one or more polymers (e.g. atactic polypropylene, styrene butadiene styrene); (2) composite sheets consisting of a polymer modified bitumen often reinforced as sometimes surfaced with various types of mats, films, foils and mineral granules.

  • MODULUS. The ratio of stress to strain.

  • MONOMER. A material composed of single molecules. A building block in the manufacture of polymers.

  • NECK DOWN. The change in the cross sectional area of a sealant as it is extended.

  • NEGATIVE SIDE WATERPROOFING. An application where in the waterproofing system and the source of hydrostatic pressure are on opposite sides of the structural element.

  • NON-FERROUS. A metal that does not contain, include or relate to iron.                                                                             

  • NON-POTABLE. Not fit or suitable for drinking

  • NON-SAG. A sealant formulation having a consistency that will permit application in vertical joints without appreciable sagging or slumping. A characteristic which allows the sealant to be installed in a sloped or vertical joint application without appreciable sagging or slumping

  • NON SHRINK. As defined by Australian standards and tested in accordance with SAA MP20.

  • NON SHRINK GROUT. A plastic/fluid material which is designed for filling a cavity for the purpose of providing the even transfer of loads to the foundation.

  • OPEN TIME. Time interval between when an adhesive is applied and when it becomes no longer workable.

  • OXIDATION. Formation of an oxide. Also the deterioration of rubbery or metallic materials due to the action of oxygen or ozone.

  • PARAPET. A low protective wall that extends above the roofline or balcony for support

  • PERCENT ELONGATION. In tensile testing, the increase in the gauge length of a specimen measured at or after fracture of the specimen within the gauge length. This is usually expressed as a percentage of the original gauge length

  • PERMEABILITY. The ability of a waterproofing material or substrate to allow the passage of water vapour through itself without blistering, permeance. The rate of water vapour transmission per unit area at a steady state through a membrane or assembly, expressed in grain/ft2 h in. Hg (ng/Pa s m2).

  • PEEL TEST. A test of an adhesive or sealant using one rigid and one flexible substrate. The flexible material is folded back (usually 180) and the substrates are peeled apart. Strength is measured in Nmm`.

  • PIGMENT. A colouring agent added to a sealant.

  • PLASTICISER. A material which is used to make a sealant or adhesive softer or more flexible.

  • POLYMER. A compound consisting of long chain-like molecules.

  • POLYSULFIDE RUBBER. Synthetic polymer usually obtained from sodium polysulfide.

  • PONDING. Water that remains on a roof 48 hours after a rain.

  • POROSITY. The density of substance and its capacity to pass liquids.

  • PORTLAND CEMENT. A mixture of certain minerals which when mixed with water forms a grey coloured paste and cures into a very hard mass.

  • POSITIVE SIDE WATERPROOFING. An application wherein the waterproofing system and the source of hydrostatic pressure are on the same side of the structural element.

  • POT LIFE. The time interval following the addition of an accelerator before chemically curing material will become too viscous to apply satisfactorily. (See Shelf Life)

  • POTABLE. Fit or suitable for drinking.

  • PREFORMED SEALANT. A sealant which is pre-shaped by the manufacturer before being shipped to the job site.

  • PRIMER. A preparatory material which is applied to joint faces in order to improve adhesion.

  • REFLECTION CRACKS. A crack through a bituminous overlay on a portland cement concrete pavement. The crack occurs above any working joint in the base pavement.

  • REINFORCEMENT. (In rubbers). Increase of modulus, toughness, tensile strength, and so forth, by the addition of selected fillers

  • STRESS. Force per unit area, usually expressed in kilopascals or kilograms per square centimetre.

  • STRESS RELAXATION. Reduction in stress in a material which is held at a constant deformation for an extended time.

  • SUBSTRATE. The surface to which a sealant or adhesive is bonded.

  • TACKINESS. The stickiness of the surface of a sealant or adhesive.

  • TEAR STRENGTH. The load required to tear apart a sealant specimen. ASTM test method D-624 expresses tear strength in pounds.

  • TENSILE STRENGTH. Resistance of a material to a tensile force (a stretch). The cohesive strength of a material, expressed in KPa at a specified elongation.

  • THERMAL MOVEMENT. The measured amount of dimensional change that a material exhibits as it is warmed or cooled.

  • THERMOPLASTIC. A material which can be repeatedly softened by heating. Thermoplastics generally have little or no chemical cross-linking.

  • THERMOSETTING. A material which hardens by chemical reaction. Not remeltable. But may be degraded by excess heat. The reaction usually gives off heat.

  • THIXOTROPIC NON -SAGGING. A material, which maintains its shape unless, agitated. A thixotropic sealant can be placed in a joint in a vertical wall and will maintain its shape without sagging during the curing process.

  • TOXIC. Poisonous or dangerous to humans by swallowing, inhalation, or contact resulting in eye or skin irritation.

  • TRAFFIC SURFACE. A surface exposed to traffic, either pedestrian or vehicular, also described as a “wear” surface.

  • TRANSVERSE JOINT. A joint perpendicular to the direction of traffic in a highway pavement.

  • UV RESISTANCE. The ability of a roof material to prevent degradation caused by exposure to Ultraviolet rays. Heat and UV are the two primary causes of premature roof failure. Oils in roofing membranes provide pliability. UV rays cause these oils dry out; this leads to the cracking of the roofing membrane. The addition of unique polymers maintains the membrane’s pliability which protects it from cracking and thus extends the waterproofing life of the membrane

  • ULTIMATE ELONGATION. Elongation at failure.

  • ULTRAVIOLET LIGHT. Part of the light spectrum. Ultraviolet rays can cause chemical changes in rubbery materials.

  • URETHANE. A family of polymers ranging from rubbery to brittle. Usually formed by the reaction of a disocyanate with a hydroxyl.

  • VAPOR BARRIER. Any material used to prevent the passage of water vapour.

  • VISCOSITY. A measure of the flow properties of a liquid or paste. Example: Honey is more viscous than water. Water (the standard of comparison) has a viscosity of 1/100 of a poise (or 1 centipoise).

  • VENT. Any outlet for air that protrudes through the roof deck such as a pipe or stack. Any device installed on the roof, gable or soffit for the purpose of ventilating the underside of the roof deck

  • VULCANISATION. Improving the elastic properties of a rubber by a chemical change.

  • WATERPROOFING. A term which refers to the process where a building component is made totally resistant to the passage of water and/or water vapour.

  • WATER VAPOR. Moisture existing as a gas in air.

  • WEATHEROMETER. An environmental chamber in which specimens are subjected to water spray and ultraviolet light.

  • WORKING LIFE. Period of time after mixing, during which a sealant or adhesive can be used.