Glossary
Remedial Terms
A
Articulated Joints
Articulated Joints are gaps placed in masonry walls, they are mainly vertical to accommodate for differential movements and are tied and sealed with flexible sealant to prevent vermin, moisture and debris ingress. Movement in masonry is generated mostly from climatic and temperature changes, differential movement in structural frames, and also from movement in foundations.
Absorption
Soaking of one substance into another (c.f asorption)
Adhesion
Bond between the coating and underlying material
Adsorption
Process of attracting a substance to a surface of a solid.
Air Dried
Coatings that dry by oxidation or solvent evaporation rather than by a catalyst or external heat
Alkali
Term applied to caustic chemicals which contain hydroxyl groups. Turns red litmus paper blue.
Alligatoring
Pronounced wide surface cracking of a coating. Resembles alligator skin.
Anode
(1) Terminal of a galvanic cell where corrosion takes place and electrons are produced. (2) The electrode connected to structure to prevent corrosion as part of a cathodic protection system.
Anodising
Generally applied to an oxide deposited electrolytically on aluminium
B
Brick growth
The expansion in brickwork commonly known as “brick growth” occurs to susceptible clay bricks, in particular under-fired batches. The expansion of clay bricks is due to the reaction with moisture in the atmosphere during the life of the masonry structure and is irreversible.
Bituminous Paint
A black or dark coloured paint using coal tar or bitumen as the binder
Bleeding
The diffusion of coloured matter through a coating from the underlying surface; also the discolouration arising from such diffusion
Blistering
Regions of isolated detachment of one or more coats resulting in rounded protuberances on the surface
Blooming or Blushing
A milky colour which forms on finishes due to atmospheric moisture or one of the solid constituents of the finish or both
C
Concrete Cancer
Concrete cancer is better known as concrete spalling. Concrete spalling is segments of concrete delaminating around corroding steel reinforcement. There are many reasons associated with the corrosion of steel and one of them is the lack concrete cover to protect the steel from moisture and air.
Cathode
Terminal of a galvanic cell which takes up the electrons produced at the anode; hydroxyl ions usually produced here
Chalking
Form of paint degradation due to weathering which results in loose pigment on the surface
Corrosion
Deterioration of a material (usually a metal) because of reaction with the environment
Cracking
Breaks in the coating that penetrate to the underlying surface.
Crocodiling
See Alligatoring
Caulking
An alternate term for “sealant”. Caulking originates from shipbuilding industry. In buildings and structures, sealants are usually used to joint parts of structures while maintaining movement, weather-tightness, or fire rating.
D
Damp proof course
Damp proof course (DPC) is a barrier built into masonry walls to prevent moisture rising into other parts of the building.
Delamination
Separation between coats or from a substrate due to very poor adhesion
DFT
Dry film thickness. The thickness of the applied coating when dry
E
Efflorescence
Efflorescence is a deposit of crystalized salts found predominantly on tiled, concrete, masonry, and rendered surfaces. The salts may arise from free lime in cement-based materials (concrete, mortar, beddings and the like), or from environmental sources, or unwashed sands. Also require the migration of water, and evaporation at or near the surface. See also rising damp.
Electrochemical
Chemical changes produced by an electrical current or the production of electricity from a chemical reaction
Environment
External conditions in which an item exists or is exposed to
F
Flashing
A thin piece of impervious material installed to prevent the passage of water into a structure, usually at changes in structural direction and/or materials (such as around window and door openings, at changes in roof line, against parapets, or at the bottom of cavities)
Fire Order
An enforceable legal instruction from Local Council to upgrade / Install fire safety measures to your building
Film
Layer of coating or paint. A wet film is one that has just been applied
Flaking
Detachment of small pieces of coating
Flash Rusting
Rusting that occurs within minutes of exposure
Flat Finish
A term usually used for decorative paints descibing a dull, non-reflective finish
Flexible
Ability of a film to bend without breaking
G
General Defect
Defects which are considered minor in importance, which (subject to context) can be repaired as part of general maintenance
Galvanizing
Coating with molten metallic zinc by dipping
Home Owners Warranty Insurance Insurance obtained by the builder for works on new residential buildings under 4 storeys high or any repair/renovations over $20K in value on any resdiential building. The insurance is to protect teh home owner against defective or incomplete works subject to statutory time periods, in the event that the builder becomes bankrupt or dissapears. High Build Coating A paint which can be applied in one coat as a relatively thick film (more than 75-125 microns) without sagging or running High Solids Coating A coating with a volume solids greater than 60 per cent Hold Point Point at which the work must be stopped for inspection and work cannot proceed until quality has been inspected and documented to comply with the specification Humidity See Relative Humidity Hydrocarbon Chemical compound containing carbon and hydrogen atoms; commonly refers to extracts from petroleum Hydrophilic Having an affinity or attraction for water Hydrophobic Repelling water Hygroscopic A compound which readily absorbs moistureH
Investigate When a problem can’t be solved by simply looking at it, investigations are carried out. These may be in the form of either pulling something apart, water testing and so on, to try and determine what the cause of the problem is. Quite often an initial visual inspection is required to determine the type of investigation that is needed. Inhibitor Compound added in small concentrations to the environment to prevent corrosionI
Jamb A jamb is the side of a window or door frame, often refered to as either the door JAMB or Window JAMB. The Flashings (see flashing) that run along side these are called jamb flashings.J
Kilopascals (kPa) Metric unit of pressure. 1 psi = 6.895 kPa.K
Letter of Intent Letter from the Principal to a Contractor confirming intent to enter into a contract. The Contract formally comes into existence upon formal acceptance of the offer by the contractor, while the Letter of Intent obliges both parties to the commitment, including a payment to the Contractor in the event that the Principal withdraws prior to execution. Landing The level area used to provide access to a stairway or ladder, or located at an intermediate level in a system of stairways or ladders. Load bearing Load bearing means a part of the structure intended to carry load (typically vertical forces) additional to those due to its own weight.L
Movement joint Joint that is made between parts of a structure for the specific purpose of permitting relative movement between the parts of the structure on either side of the joint. Mezzanine An intermediate floor within a room Magnesite Lightweight floor levelling (primary purpose) and sound attenuation material (secondary benefit). Has a chloride binder which leaches out when wet, and leads to corrosion. Note: Because of the chloride component, does not always arise with expansion and spalling, so can be difficult to detect by laypeople until advanced. May also contain asbestos as part of binder. Megapascals (Mpa) Metric unit of pressure equal to a force of one Newton (9.8 kg weight) on one square millimetre. 1 MPa is approximately equal to 145 psi. MSDS Material Safety Data SheetM
Non-compliance Failure to achieve the performance or prescriptive criteria demanded by a regulation or other statutory requirement. A non-compliance may lead to remedial work, non-approval of project completion, or in extreme cases to demolition.N
Overflow spout A pipe projecting laterally from a roof, balcony or gutter to mitigate internal overflows by allowing the free discharge of rainwater in the event of excessive quantities of rain water or blocked downpipes. Overhang The projection of a roof or floor beyond the line of the wall which carries it, including any fascia but excluding any gutter. Orange Peel Dimpled appearance of a coated surface resembling the skin of an orange, due to lack of flow out of wet film. Oxidation Reaction which takes place at the anode. During corrosion, it is the reaction of the metal to form metal ions.O
Parapet Parapets in exterior walls are perpetual problems. The parapet is exposed to the environment on both its faces and at its top (coping). It is exposed to rain, wind and high/low temperatures without any help and protection from air conditioning and heating. The parapet is thus subjected to the greatest number of freeze-thaw cycles and therefore is typically the first element to show deterioration. Extracted from Kaminetzy (1991) Design and Construction Failures: Lessons from Forensic Investigations, p291. Polyurethane Membrane A liquid applied membrane that has a polyurethane base. Typically used in wet areas, balconies and planters. The polyurethane is not UV stable and needs protection in exposed applications. Ponding If falls on tiles are not consistent and uniform to the outlets water will not freely drain and surface water ponding occurs. pH Value indicating the acidity of a solution and is a measure of the concentration of hydrogen ions. Pure water has a pH value of 7 and is neutral. Acids range down to pH 0 becoming increasingly strongly acidic and alkalis range from pH 7 up to 14 becoming increasingly strongly alkaline. Pinholes Formation of tiny, circular holes in the dry film. Pitting Result of local corrosive attack forming deep or shallow holes in a metal surface. Porosity Small voids through which fluids may penetrate.P
Quantity Surveyor A building professional who is expert in building costs, both before and after construction.Q
Riser 1. In a staircase the part of the stair that is vertical or the difference in height between the treads. 2. A part of a building used to contain services shared between floors, typically in a fire rated compartment. Reglet A sawcut termination into the substrate used to secure waterproofing or flashing details. Usually over-flashed with supplementary details. Relative Humidity Measure of the moisture content of air. Ratio of the quantity of water vapour actually present in the air to the greatest amount possible at a given temperature. Expressed in percent. Rust The result of the corrosion of iron or steel to form visible iron oxide.R
Spalling Typically occurs on concrete elements with steel reinforcing, but can also arise on parts on a structure (including masonry elements) at points of high local pressure. For concrete spalling see also concrete cancer. As the concrete ages its natural protection against the corrosion of the embedded steel reinforcing is reduced and the steel close to the surface will corrode. As steel corrodes it expands and cracks the concrete, which ultimately detaches as a spall. Screed An alternate term for bedding or topping. Sometimes the straight-edge tool used to place the bedding is also called a screed. Structural damage We define structural damage as damage to any element of a structure load bearing or water proofing parts of the structure that reduces or can act to reduce the safe load carrying capacity of the element below the capacity for which it was designed, or which can reduce the normally expected level of habitability of a structure.S
Tender An offer from a contractor to undertake particular works for a nominated price. The tender should be included in the contract documents. Tender documents The documents provided to contractors (usually by a consultant) to detail the works required, specification, proposed contract terms and details or any other detail or constraint particular to the site. Topping Usually a sand and cement or concrete mix placed to create falls. Toppings can be placed under membranes, tiles or left exposed. Toppings under tiles must be carefully detailed to reduce the potential for efflorescence occurring.T
Underpinning Insertion of a new foundation under an existing foundation. Undercutting The spread of corrosion beneath a coating from a break in the firm or the edge.U
Void An open space (at large scale) or break in material consistency (within building components).V
Waterproofing system A combination of elements that is required to achieve a waterproof barrier to prevent water passing to parts of a structure that it is not desired. The entire Waterproofing System may include hobs, falls, membranes, outlets, flashings, waterstops and sealants. Wet Film Designates the coating after application but before the solvent evaporates. The solvent content in the wet film will constantly decrease due to evaporation. White Rust White corrosion products on a zinc surface.W
X
Y
Zed flashing See Also flashing. A zed flashing is a one-piece flashing shaped like a Z, used between stepped parts of buildings, like adjoining planter boxes.Z