A coating’s ability to withstand rubbing, scuffing and mechanical wear without significant damage. It is especially important on high-traffic or frequently cleaned surfaces, where a suitably durable coating should be specified.
See also: Cleanability; Durability; Scrubbability; Washability
Paint using an acrylic resin as part of its binder system. Many modern water-based coatings use acrylic technology for adhesion, durability, colour retention and flexibility, although performance varies by product.
See also: Binder; Emulsion Paint; Water-Based Paint
How effectively a coating bonds to the surface beneath it. Poor adhesion can cause peeling, flaking or blistering and is often linked to contamination, moisture, inadequate preparation or incompatible coatings.
See also: Bonding Primer; Coating Failure; Primer; Surface Preparation
A coating’s ability to withstand alkaline substrates such as concrete, cement render and some plaster surfaces without deterioration. The substrate should be adequately cured and the coating suitable for its condition.
See also: Alkali-Resistant Primer; Cementitious Surface; Masonry Paint
A primer formulated for alkaline mineral surfaces such as cement render and concrete. It helps protect subsequent coatings from alkalinity but does not replace correct curing and surface preparation.
See also: Alkali Resistance; Cementitious Surface; Primer
Paint using an alkyd resin as its binder, traditionally associated with solvent-based gloss, satin and undercoat systems. Alkyd coatings are valued for flow, levelling and durability, particularly on wood and metal.
See also: Binder; Gloss Paint; Solvent-Based Paint; Undercoat
A protective coating designed to reduce carbon dioxide penetration into concrete. It is mainly used in building maintenance and concrete protection, where correct diagnosis and preparation are essential.
See also: Carbonation; Concrete; Protective Coating
A primer designed to help protect metal against corrosion while providing a base for subsequent coatings. Selection should reflect the metal, exposure conditions and intended finishing system.
See also: Corrosion; Metal Primer; Rust; Surface Preparation
A coating formulated to help resist mould growth on the finished surface, commonly used in areas prone to condensation or high humidity. It is not a substitute for correcting persistent moisture or ventilation problems.
See also: Condensation; Fungicidal Wash; Mould; Ventilation
A coating designed to increase surface grip and reduce slip risk, commonly used on floors, steps and walkways. Preparation, application rate and any required aggregate are important to performance.
See also: Floor Paint; Floor Preparation; Specialist Coating
The process by which liquid paint is broken into fine droplets during spray application. Pressure, tip selection, viscosity and equipment setup all affect atomisation and the resulting finish.
See also: Airless Spraying; Spray Application; Spray Tip
Working freshly applied paint into a surface with a brush, often after spraying or rolling. It can improve penetration and distribution on textured, porous or uneven surfaces.
See also: Back Rolling; Brush Application; Wet Edge
Applying primer or protective coating to the concealed face of timber before installation. It can help reduce uneven moisture movement, particularly on exterior joinery and cladding.
See also: End Grain; Exterior Woodcare; Primer; Timber Moisture
Passing a roller over freshly spray-applied paint while it remains wet. It can help work paint into porous or textured surfaces and produce a more consistent finish.
See also: Back Brushing; Roller Application; Spray Application; Wet Edge
A coating used to isolate a problematic substrate, contaminant or existing coating from the new decorative system. The source of staining or contamination should still be identified and corrected where possible.
See also: Primer; Sealer; Stain Blocking
A preparatory or intermediate coating applied before the final finish. It may improve adhesion, opacity, colour uniformity or protection and must be compatible with the full coating system.
See also: Primer; Topcoat; Undercoat
A code identifying a particular production batch of paint or coating. On large uninterrupted areas, checking batch numbers can help manage the risk of subtle colour variation.
See also: Colour Consistency; Opacity
The resin or polymer component of paint that holds pigment together and forms the continuous coating film. Binder technology strongly influences adhesion, flexibility, durability and washability.
See also: Acrylic Paint; Alkyd Paint; Pigment; Resin
A protective coating containing bituminous material, used for certain metal, masonry and waterproofing applications. Bituminous surfaces may require special preparation before conventional decoration.
See also: Barrier Coat; Protective Coating; Stain Blocking
Migration of material from the substrate or an existing coating into a new paint film, causing staining or discolouration. The source should be identified before applying a suitable isolating system.
See also: Barrier Coat; Stain Blocking; Tannin Staining
A coating defect where bubbles or raised areas develop within or beneath the paint film. Common causes include moisture, poor adhesion, excessive heat and incompatible systems.
See also: Adhesion; Coating Failure; Flaking; Peeling
Sticking between two painted surfaces after they are brought into contact, such as a door sticking to its frame. Adequate drying and curing time helps reduce the risk.
See also: Block Resistance; Curing; Drying Time
A dried coating’s ability to resist sticking when painted surfaces are pressed together. It is particularly relevant to doors, windows, cupboards and shelving.
See also: Blocking; Curing; Drying Time
A defect producing a dull, cloudy or milky appearance in a coating, often associated with moisture, condensation, low temperature or unsuitable drying conditions.
See also: Condensation; Curing; Humidity
A primer formulated to improve adhesion to difficult, smooth or low-porosity surfaces. Cleaning and preparation remain essential even when a specialist bonding primer is used.
See also: Adhesion; Primer; Surface Preparation
The ability of a coating system to allow water vapour to pass through it. This can be important on mineral masonry and older buildings where moisture needs to escape.
See also: Masonry Paint; Moisture; Permeability
Applying paint with a decorating brush, particularly useful for cutting in, trim and detailed surfaces. Brush selection, loading and maintaining a wet edge influence finish quality.
See also: Brush Loading; Cutting In; Wet Edge
Resistance felt as a brush moves through paint across a surface. Excessive drag can contribute to visible marks and may be influenced by coating, temperature, substrate and brush choice.
See also: Brushability; Brush Marks; Open Time
Taking the correct amount of paint onto a brush before application. Correct loading helps maintain application speed and an even film while reducing drips and drag.
See also: Brush Application; Brushability; Cutting In
Visible lines or ridges left after brush application. They can result from unsuitable tools, excessive brushing, incorrect film thickness or paint drying too quickly.
See also: Brushability; Brush Drag; Levelling
How easily a paint can be applied and distributed using a brush. Good brushability allows even spreading without excessive drag while maintaining control and film build.
See also: Brush Application; Brush Drag; Brush Loading
The appearance of bubbles in a wet or drying paint film. Causes can include trapped air, porous substrates, excessive agitation or unsuitable application conditions.
See also: Blistering; Coating Failure; Porosity
The thickness of a coating film produced by one or more coats. Correct build is important for opacity, durability and protection; excessive build can cause runs or curing problems.
See also: Coverage Rate; Film Thickness; Wet Film Thickness
An intermediate coating designed to increase overall film thickness, commonly used in protective systems where a defined film build is required.
See also: Build; Film Thickness; Protective Coating
The total thickness achieved by a coating system. Protective specifications may state required wet or dry film thicknesses to achieve intended performance.
See also: Build; Dry Film Thickness; Wet Film Thickness
Sanding through a coating and exposing the layer or substrate beneath, often on edges and raised details. Careful technique and suitable abrasives reduce the risk.
See also: Abrasives; Denibbing; Sanding; Surface Preparation
A change in sheen caused by rubbing or repeated cleaning, making part of a painted surface appear smoother or shinier. It is particularly noticeable on matt finishes.
See also: Abrasion Resistance; Cleanability; Durable Paint; Scrubbability
A joint where two materials meet edge-to-edge without overlapping. Decorators encounter butt joints in plasterboard, timber and wallcoverings, where correct preparation helps minimise visible lines or cracking.
See also: Filling; Jointing; Surface Preparation
The movement of liquid through small pores or spaces within a material. In buildings it can contribute to moisture movement through masonry and other porous substrates.
See also: Damp; Masonry; Moisture; Porosity
Filling small gaps and joints with a flexible, paintable sealant before decoration, commonly around skirting, architraves and frames.
See also: Flexible Filler; Filling; Sealant
A substrate containing cement, such as concrete, cement render or mortar. New cementitious materials may contain significant moisture and alkalinity and require suitable curing and preparation.
See also: Alkali Resistance; Concrete; Masonry Paint; Render
Formation of a loose powdery residue on a paint film, commonly as exterior coatings weather. Heavy chalking can prevent good adhesion and should be removed or stabilised as appropriate.
See also: Adhesion; Exterior Paint; Stabilising Solution; Surface Preparation
A coating’s ability to withstand specified chemicals without significant softening, staining, blistering or deterioration.
See also: Durable Coating; Epoxy Coating; Protective Coating
How easily dirt and marks can be removed without damaging the coating. It is important in schools, healthcare, hospitality and other frequently cleaned environments.
See also: Abrasion Resistance; Durability; Scrubbability; Washability
The process by which polymer particles in many water-based paints join during drying to form a continuous film. Low temperatures can interfere with correct film formation.
See also: Curing; Drying Time; Film Formation; Water-Based Paint
An individual layer of paint or coating within a decorating system. A system may include primer, undercoat, intermediate and finishing coats.
See also: Film Build; Primer; Topcoat; Undercoat
A material applied to a surface for decoration, protection or both. Paints, primers, stains, varnishes and specialist protective products are all coatings.
See also: Paint; Primer; Protective Coating; Topcoat
Premature deterioration of a coating system, seen as peeling, flaking, blistering, cracking or loss of adhesion. Moisture, contamination and poor preparation are common causes.
See also: Adhesion; Blistering; Flaking; Peeling; Surface Preparation
The complete combination of preparation treatments and coating layers used on a substrate. Each component must be compatible and applied to specification.
See also: Primer; Specification; Topcoat; Undercoat
An internal surface significantly colder than surrounding air, potentially causing condensation and mould. Persistent problems should be investigated rather than repeatedly painted over.
See also: Condensation; Mould; Surface Temperature; Ventilation
Uniformity of colour across a decorated surface and between containers. Batch control, consistent application and film thickness all influence the result.
See also: Batch Number; Colour Matching; Opacity
A colour’s ability to retain its appearance when exposed to light, weathering or cleaning.
See also: Colour Retention; Exterior Paint; UV Resistance
The process of reproducing a specified colour using formulations, standards, physical samples or electronic colour-reading equipment.
See also: Colour Consistency; Colour Sample; Metamerism; Sheen
A coating’s ability to maintain its original colour over time despite UV exposure, weathering, chemicals or cleaning.
See also: Colour Fastness; Exterior Paint; UV Resistance; Weathering
Whether a coating can be successfully used with a substrate, primer, existing coating or subsequent finish. Incompatibility can cause lifting, wrinkling or poor adhesion.
See also: Adhesion; Bonding Primer; Coating Failure; Primer
A construction material made principally from cement, aggregates and water. Before coating, consider age, moisture, contamination, condition and intended exposure.
See also: Anti-Carbonation Coating; Cementitious Surface; Floor Paint; Masonry Coating
Water forming when airborne moisture meets a colder surface. Persistent condensation can contribute to mould and coating deterioration and should be addressed before redecorating.
See also: Cold Wall; Mould; Ventilation
A water-based interior paint commonly used on walls and ceilings in new-build, refurbishment and commercial work. Check product-specific durability and substrate suitability.
See also: Emulsion Paint; Matt Paint; New Plaster; Mist Coat
Deterioration of metal through chemical or electrochemical reaction with its environment. Successful decoration requires removal of unstable material and an appropriate protective system.
See also: Anti-Corrosive Primer; Metal Preparation; Rust
The approximate area a quantity of paint should cover, commonly stated in square metres per litre. Actual coverage varies with porosity, texture, method and film thickness.
See also: Film Build; Opacity; Porosity; Spreading Rate
Splits developing through or across a paint film. Causes include excessive film build, substrate movement, ageing or incompatible systems.
See also: Coating Failure; Flaking; Peeling; Surface Preparation
Small circular depressions in a coating film, often caused by contamination, trapped air or surface-tension effects. Identify and remove the cause before recoating.
See also: Contamination; Fish Eyes; Surface Preparation
A network of fine cracks across a coating, sometimes resembling cracked glaze. It can result from ageing, excessive build or incompatible layers.
See also: Cracking; Coating Failure; Film Build
A chemical process in which polymer chains form links during curing, increasing properties such as hardness and chemical resistance in certain coatings.
See also: Curing; Two-Pack Coating
The process by which a coating develops its final film properties after application. A coating can be touch-dry well before it is fully cured.
See also: Drying Time; Hardness; Recoat Time
Controlled brush application around edges, corners, ceilings and trim before or alongside roller application. Maintaining a wet edge helps reduce visible differences.
See also: Brush Application; Roller Application; Wet Edge
A defect where excessive wet coating flows down a vertical surface in broad runs or folds. It is commonly linked to over-application or incorrect spray setup.
See also: Film Build; Runs; Sagging; Spray Application
Unwanted moisture within a building fabric or surface. Before decorating, identify and correct the source where possible and ensure the substrate is suitable for coating.
See also: Condensation; Moisture; Rising Damp
A specialist coating intended for defined moisture-control applications. It should only be used where appropriate to the diagnosed problem and manufacturer specification.
See also: Damp; Moisture; Specialist Coating
Removing grease, oil and similar contamination before painting. Residual contamination can seriously reduce adhesion.
See also: Contamination; Surface Preparation
Lightly abrading a dried coating between coats to remove small nibs, dust particles or raised fibres and improve smoothness.
See also: Abrasives; Sanding; Surface Preparation
The temperature at which airborne moisture begins to condense. It is important in exterior and protective coating work because condensation on a substrate can impair adhesion and curing.
See also: Condensation; Humidity; Surface Temperature
The thickness of a coating after it has dried or cured. Protective systems may require a specified dry film thickness to achieve intended performance.
See also: Film Build; Wet Film Thickness
The period required for a coating to reach a stated stage of dryness. Touch-dry, hard-dry, recoat and full cure are different stages and should not be confused.
See also: Curing; Recoat Time
A matt-finish wall paint formulated to provide greater resistance to cleaning, marking and wear than a standard matt emulsion.
See also: Cleanability; Matt Paint; Scrubbability
A protective sheet used to cover floors, furniture and fittings during decorating. Select a type appropriate to the surface and task.
See also: Surface Protection
White crystalline salts deposited on masonry or mineral surfaces as moisture moves through the substrate and evaporates. The moisture source should be addressed before decoration.
See also: Damp; Masonry; Moisture
A low- to mid-sheen finish commonly used on interior woodwork, metal and, in some formulations, walls. Performance and sheen vary by product.
See also: Gloss Paint; Satin Paint; Sheen
A broad term commonly used in the UK for water-based decorative wall and ceiling paints. Products range from contract matt to highly durable finishes.
See also: Contract Emulsion; Matt Paint; Water-Based Paint
The exposed ends of timber fibres, which can absorb moisture and coatings more readily than face grain. Exterior end grain often requires particular attention during preparation and coating.
See also: Back Priming; Exterior Woodcare; Timber Moisture
A high-performance coating based on epoxy resin, often supplied as a two-component system for floors, metal and demanding commercial or industrial environments.
See also: Chemical Resistance; Floor Coating; Two-Pack Coating
A primer designed to promote adhesion to certain metal surfaces through chemical action. Use only where suitable for the metal and coating system.
See also: Metal Primer; Surface Preparation
Paint formulated for outdoor exposure, where resistance to weathering, moisture and UV light is important. Select products specifically suited to the substrate.
See also: Masonry Paint; UV Resistance; Weathering
Loss or change of colour over time, commonly due to UV exposure, weathering or chemical effects.
See also: Colour Fastness; Colour Retention; UV Resistance
A smoothly tapered edge created when sanding or preparing a repair so the transition into the surrounding surface is less visible.
See also: Filling; Sanding; Surface Preparation
A material used to repair holes, cracks and surface imperfections before decoration. Select the filler according to substrate, depth, movement and interior or exterior exposure.
See also: Caulking; Filling; Surface Preparation
The thickness accumulated by one or more coating layers. Correct film build is important for opacity, protection and durability.
See also: Build; Dry Film Thickness; Wet Film Thickness
The process by which an applied coating develops into a continuous film as it dries or cures. Temperature, humidity and ventilation can affect the process.
See also: Coalescence; Curing; Drying Time
Small circular defects where wet paint pulls away from contaminated areas, often associated with oil, silicone or similar surface contamination.
See also: Contamination; Cratering; Degreasing
Loss of paint in flakes where the coating has lost adhesion or cohesion. The underlying cause must be corrected before repainting.
See also: Adhesion; Coating Failure; Peeling
Rapid light rust formation on ferrous metal after contact with moisture, sometimes occurring during preparation or with water-based coatings.
See also: Corrosion; Metal Primer; Rust
A very low-sheen finish that reflects little light and can help disguise minor surface imperfections.
See also: Matt Paint; Sheen
A coating formulated for floors and designed to withstand foot traffic or other specified service conditions. Preparation and substrate compatibility are critical.
See also: Anti-Slip Coating; Epoxy Coating; Floor Preparation
The ability of wet paint to spread and settle after application. Good flow can help reduce brush or roller texture.
See also: Levelling; Open Time
A treatment used to kill or remove fungal growth before decoration, according to the product instructions. The moisture conditions encouraging growth should also be addressed.
See also: Anti-Mould Paint; Mould; Surface Preparation
Steel protected by a zinc coating. It requires suitable cleaning, preparation and compatible primers or direct-to-metal coatings before decoration.
See also: Metal Primer; Zinc
A high-sheen decorative finish commonly used on wood and metal. Modern gloss products may be water-based, solvent-based or use hybrid technologies.
See also: Eggshell; Satin Paint; Sheen
A decorating term for the underlying colour or substrate showing through the finish because opacity or film build is insufficient.
See also: Coverage Rate; Opacity; Undercoat
A material used to fill joints between tiles or masonry units. When decorating adjacent areas, ensure grout is cured, clean and suitable for any intended coating.
See also: Cementitious Surface; Surface Preparation
A stage of drying at which a coating has developed substantial hardness, although full cure may still take longer.
See also: Curing; Drying Time
A coating’s resistance to indentation, scratching or deformation. Final hardness may not develop until the coating is fully cured.
See also: Curing; Durability
A wood finish combining oils and waxes to protect and enhance timber, commonly used on floors, furniture and interior wood. Product-specific preparation and maintenance instructions should be followed.
See also: Floor Finish; Wood Oil; Woodcare
The ability of a coating to obscure the colour or pattern beneath it. It is closely related to opacity and application thickness.
See also: Coverage Rate; Opacity
A coating designed to achieve a relatively thick film in one or more coats, often used for protective or specialist applications.
See also: Film Build; Protective Coating
The amount of water vapour in the air. High humidity can slow drying and increase condensation risk, while very low humidity can shorten open time.
See also: Condensation; Drying Time; Open Time
The waiting period required after mixing certain multi-component coatings before application. Where specified, it is essential to correct curing and performance.
See also: Pot Life; Two-Pack Coating
A specialist fire-protection coating designed to expand when exposed to heat and help insulate the substrate. It must be applied as part of a tested, specified system.
See also: Protective Coating; Specialist Coating
A group of compounds associated with rust and also used as pigments. On steel, unstable rust should be correctly prepared before coating.
See also: Corrosion; Rust
A primer used to separate a problematic substrate or stain from subsequent coatings. Product selection depends on the contaminant and finishing system.
See also: Barrier Coat; Stain Blocking
A material used to fill and finish plasterboard joints before decoration. It should be dry, sound and suitably prepared before painting.
See also: Filling; Plasterboard; Surface Preparation
The process of preparing and finishing joints between materials such as plasterboard sheets. Correct jointing helps minimise visible lines and cracking after decoration.
See also: Butt Joint; Joint Compound
A surface texture or condition that provides sufficient grip for a subsequent coating. Light abrasion is sometimes used to create a mechanical key on smooth surfaces.
See also: Adhesion; Sanding; Surface Preparation
A sealing treatment traditionally used on resinous knots in timber to reduce staining through subsequent paint coats. Modern stain-blocking primers may also be specified depending on the system.
See also: Stain Blocking; Tannin Staining; Timber
A weak, powdery layer that can form on the surface of concrete or cementitious materials. It should be removed before applying floor or protective coatings.
See also: Concrete; Floor Preparation; Surface Preparation
A visible difference in colour or sheen where one area of paint overlaps another after the first has begun to dry. Maintaining a wet edge helps reduce lap marks.
See also: Open Time; Wet Edge
The ability of wet paint to flow out after application and reduce brush marks, roller texture or other surface irregularities.
See also: Flow; Open Time
A wallcovering used to provide a more uniform surface before painting or hanging decorative wallpaper. Joints and edges should be correctly prepared to avoid showing through the finish.
See also: Wallcovering; Surface Preparation
A description used for coatings formulated with relatively low levels of volatile organic compounds. Always refer to the product’s stated VOC classification or technical information.
See also: VOC; Water-Based Paint
An exterior coating formulated for suitable masonry surfaces such as render, brick or concrete. Breathability, weather resistance and substrate condition should be considered when selecting a system.
See also: Breathability; Exterior Paint; Render
A low-sheen finish widely used on walls and ceilings. Different matt paints offer very different levels of durability, cleanability and suitability for new plaster.
See also: Contract Emulsion; Durable Matt; Sheen
Medium-density fibreboard, an engineered wood panel. Cut edges are highly absorbent and normally require appropriate sealing and preparation before finishing.
See also: Primer; Timber
A primer formulated for a specified metal substrate to promote adhesion and, where required, corrosion protection.
See also: Anti-Corrosive Primer; Corrosion; Surface Preparation
A colour-matching effect where two colours appear to match under one light source but differ under another.
See also: Colour Matching; Lighting
A coating designed to allow a degree of water-vapour transmission while protecting the substrate. The term is commonly encountered in exterior woodcare and masonry systems.
See also: Breathability; Permeability
A common term for superficial fungal growth associated with damp or humid conditions. Treat growth and address the moisture source before redecorating.
See also: Anti-Mould Paint; Fungicidal Wash; Mould
A first coat applied to suitable new or bare plaster to manage absorbency and provide a sound base for subsequent decoration. Follow the paint manufacturer’s instructions for product choice and dilution.
See also: Contract Emulsion; New Plaster; Porosity
The amount of moisture present in a material. Excess moisture in timber, plaster, masonry or concrete can contribute to coating failure.
See also: Damp; Timber Moisture
Fungal growth encouraged by persistent moisture, condensation and poor ventilation. Existing growth should be treated and underlying conditions addressed before repainting.
See also: Anti-Mould Paint; Condensation; Fungicidal Wash; Ventilation
The pile length of a roller sleeve. Shorter piles are generally suited to smoother surfaces, while longer piles can help work coatings into rougher textures.
See also: Roller Sleeve; Roller Application
Recently applied plaster that must be sufficiently dry and sound before decoration. Use a suitable first-coat system according to the paint manufacturer’s instructions.
See also: Contract Emulsion; Mist Coat; Porosity
A small raised particle or imperfection in a dried coating film, often caused by dust or debris. Light denibbing between coats can improve finish quality.
See also: Denibbing; Surface Preparation
A surface that absorbs little or no liquid, such as some plastics, tiles and dense existing coatings. Such surfaces may require cleaning, abrasion or a bonding primer.
See also: Bonding Primer; Surface Preparation
A coating’s ability to hide the colour or pattern beneath it. Opacity is affected by formulation, colour, film thickness and substrate.
See also: Coverage Rate; Hiding Power
The period during which freshly applied paint remains workable before it begins to set. Temperature, humidity, airflow and coating type all affect open time.
See also: Brush Marks; Levelling; Wet Edge
A textured paint-film defect resembling orange skin, commonly associated with spray application or poor levelling.
See also: Atomisation; Levelling; Spray Application
Applying one coating over another. The previous coat should be sufficiently dry and the new product compatible with the existing system.
See also: Compatibility; Recoat Time
Fine spray droplets that travel beyond the intended target area. Correct masking, extraction, equipment setup and spray technique help control it.
See also: Atomisation; Spray Application
A smaller container used to hold a manageable quantity of paint during brush work and cutting in.
See also: Brush Application; Cutting In
Loss of coating in strips or sheets due to poor adhesion or failure within the coating system. Identify and correct the cause before repainting.
See also: Adhesion; Coating Failure; Flaking
The ability of a material or coating to allow gases or vapour to pass through it. It is relevant to breathable masonry and some woodcare systems.
See also: Breathability; Microporous Coating
Fine particles used in paint to provide colour, opacity or other properties. Pigment selection can influence hiding power, colour retention and durability.
See also: Binder; Colour Retention; Opacity
Tiny holes appearing in a coating film, often linked to air release, porous substrates or application conditions.
See also: Porosity; Surface Preparation
A gypsum-based sheet material widely used for internal walls and ceilings. Joints, fixings and absorbency differences should be correctly prepared before decoration.
See also: Joint Compound; Jointing; Mist Coat
The degree to which a substrate absorbs liquid. Highly porous surfaces can affect coverage, drying and appearance and may require appropriate priming or sealing.
See also: Coverage Rate; Mist Coat; Sealer
The usable working time of a mixed multi-component coating before it becomes unsuitable for application.
See also: Induction Time; Two-Pack Coating
A preparatory coating applied directly to a substrate to promote adhesion, seal porosity, inhibit corrosion or perform another defined function.
See also: Basecoat; Bonding Primer; Undercoat
A coating primarily specified to protect a substrate against environmental, chemical or mechanical exposure.
See also: Anti-Corrosive Primer; Specialist Coating
Polyvinyl chloride, a plastic used in building products. Painting PVC requires correct cleaning and a coating system confirmed as suitable for the specific surface.
See also: Bonding Primer; Non-Porous Surface
A coating formulated to reach specified drying stages relatively quickly. Fast drying can improve productivity but may reduce open time during application.
See also: Drying Time; Open Time; Recoat Time
The minimum or recommended period before applying the next coat. Applying too soon or waiting beyond a specified recoat window can affect some systems.
See also: Curing; Drying Time
A cementitious or other protective finish applied to external or internal walls. Before painting, render should be sound, adequately cured and suitable for the coating system.
See also: Cementitious Surface; Masonry Paint
A key film-forming component of many paints and coatings. Resin type strongly influences adhesion, hardness, flexibility and chemical resistance.
See also: Binder; Curing
Applying paint using a roller. Sleeve pile, loading, pressure and working method should suit the coating and surface texture.
See also: Nap; Roller Sleeve; Wet Edge
The replaceable fabric or foam component of a paint roller. Material and pile length should be selected for the coating and substrate.
See also: Nap; Roller Application
Narrow downward flows of excess wet paint on a vertical surface, usually caused by over-application or poor technique.
See also: Curtaining; Sagging
The corrosion product formed on iron and steel in the presence of oxygen and moisture. Unstable rust should be removed and the metal correctly protected before finishing.
See also: Anti-Corrosive Primer; Corrosion; Metal Primer
Downward movement of wet paint that produces uneven film thickness, runs or curtains. It is commonly caused by excessive application.
See also: Curtaining; Runs
Abrading a surface to smooth defects, remove unstable material or create a key for subsequent coatings. Use the appropriate abrasive and control dust.
See also: Abrasives; Denibbing; Surface Preparation
A mid-sheen finish commonly used on wood and metal and, in some formulations, walls. It offers less shine than gloss while retaining a more reflective finish than matt.
See also: Eggshell; Gloss Paint; Sheen
A coating’s ability to withstand repeated cleaning or scrubbing without unacceptable damage. It is an important specification factor in high-traffic interiors.
See also: Abrasion Resistance; Cleanability; Durable Matt
A preparatory coating used to reduce absorbency, isolate a surface or provide a more uniform base for decoration.
See also: Porosity; Primer; Stain Blocking
The degree of light reflection from a coating surface. Common decorative descriptions include matt, eggshell, satin and gloss.
See also: Eggshell; Gloss Paint; Matt Paint; Satin Paint
A fast-drying specialist primer based on shellac, commonly used for difficult stain blocking and sealing applications. Check compatibility and product instructions.
See also: Barrier Coat; Stain Blocking
Silicone residue on a surface that can cause severe wetting and adhesion defects in subsequent coatings. It should be removed as thoroughly as possible before painting.
See also: Contamination; Fish Eyes
Paint in which organic solvent is a principal carrier. Traditional alkyd gloss and undercoat systems are common examples.
See also: Alkyd Paint; Water-Based Paint; VOC
Small droplets of paint thrown from a roller or brush during application. Correct loading, tool choice and technique help reduce it.
See also: Roller Application
Applying a coating as atomised droplets using spray equipment. Correct equipment setup, masking, ventilation and technique are essential.
See also: Airless Spraying; Atomisation; Overspray
The area a coating is intended to cover at a specified film thickness, usually expressed in square metres per litre.
See also: Coverage Rate; Film Build
Using a specialist primer or sealer to prevent stains or contaminants migrating into the finishing coat. The source should still be diagnosed and corrected where possible.
See also: Barrier Coat; Bleeding; Sealer
A treatment used on suitable friable or powdery mineral surfaces to bind loose material before decoration. It should not be used automatically on every masonry surface.
See also: Chalking; Masonry Paint; Surface Preparation
The underlying material or surface to which a coating is applied. Correct substrate identification is fundamental to preparation and product selection.
See also: Primer; Surface Preparation
The cleaning, repair and treatment required to make a substrate suitable for coating. Good preparation is fundamental to adhesion and finish quality.
See also: Adhesion; Degreasing; Sanding
The temperature of the surface being coated. It can differ from air temperature and affect condensation, drying and curing.
See also: Dew Point; Drying Time
Brown or yellow discolouration caused by natural extractives migrating from timber into a coating. Suitable sealing or stain-blocking systems may be required.
See also: Bleeding; Stain Blocking; Timber
Moisture contained within wood. Excessive or uneven moisture can contribute to movement, poor adhesion and premature coating failure.
See also: Back Priming; End Grain; Moisture Content
The final coat or coats in a coating system, providing the intended colour, sheen and surface performance.
See also: Basecoat; Primer; Undercoat
A drying stage at which a coating can be lightly touched without transferring paint. It does not mean the coating is fully cured or ready for service.
See also: Curing; Drying Time
A coating supplied as two components that are mixed before use to trigger a chemical cure, commonly used for demanding floor, metal and protective applications.
See also: Epoxy Coating; Pot Life; Curing
An intermediate coating applied between primer and topcoat in systems that require it. It can improve opacity, build and the uniformity of the final finish.
See also: Basecoat; Primer; Topcoat
A coating’s ability to resist deterioration caused by ultraviolet radiation. It is particularly important for exterior colour and clear wood finishes.
See also: Colour Retention; Exterior Paint; Weathering
The degree to which a coating allows water vapour to pass through it. It is relevant when specifying breathable systems for masonry and older buildings.
See also: Breathability; Permeability
A transparent or translucent protective finish used on timber and other suitable surfaces. Varnishes may be water-based, solvent-based or specialist formulations.
See also: Clear Coat; Woodcare
A liquid’s resistance to flow. Paint viscosity affects brush, roller and spray application and should only be adjusted in accordance with product instructions.
See also: Atomisation; Flow; Spray Application
Volatile organic compounds are organic chemicals that evaporate readily. Decorative coatings carry VOC information or classifications to help users understand solvent emissions.
See also: Low VOC; Solvent-Based Paint; Water-Based Paint
A decorative material applied to walls, including wallpaper, vinyl and specialist coverings. Substrate preparation, adhesive choice and joint treatment affect the final result.
See also: Lining Paper; Surface Preparation
A coating’s ability to withstand cleaning without unacceptable damage or colour loss. Product-specific performance should be considered for frequently cleaned spaces.
See also: Cleanability; Durable Matt; Scrubbability
Paint in which water is the principal carrier. Modern water-based coatings include emulsions, trim paints, primers and specialist products.
See also: Acrylic Paint; Emulsion Paint; Solvent-Based Paint
Gradual change to a coating caused by outdoor exposure, including sunlight, rain, temperature variation and pollution.
See also: Colour Retention; Exterior Paint; UV Resistance
The still-wet boundary of freshly applied paint. Maintaining a wet edge helps prevent lap marks and visible differences in texture or sheen.
See also: Cutting In; Lap Mark; Open Time
The thickness of a coating immediately after application. It can be measured on suitable coatings to help achieve the specified dry film thickness.
See also: Dry Film Thickness; Film Build
An oil-based or water-emulsified finish designed to penetrate and protect suitable timber while retaining a natural appearance.
See also: Hardwax Oil; Woodcare
A coating designed to colour timber while allowing the grain to remain visible. Exterior wood stains may also provide weather protection as part of a system.
See also: Exterior Woodcare; Woodcare
The preparation, protection and finishing of timber using products such as stains, oils, varnishes, preservatives and opaque coatings.
See also: Hardwax Oil; Varnish; Wood Oil; Wood Stain
An organic solvent found in some specialist coatings and cleaning products. Follow the product safety data and handling instructions where it is present.
See also: Solvent-Based Paint; VOC
A colour change in which a coating develops a yellow tone over time. It is particularly associated with some traditional alkyd coatings and can be influenced by light exposure and ageing.
See also: Alkyd Paint; Colour Retention
A protective primer containing zinc or zinc compounds, used in specified systems to help protect steel from corrosion.
See also: Anti-Corrosive Primer; Corrosion; Metal Primer
A specialist primer containing a high proportion of zinc in the dry film, used for corrosion protection of prepared steel in appropriate protective systems.
See also: Protective Coating; Zinc Primer
Deposits that can form on zinc or galvanised surfaces under certain exposure conditions. They should be correctly assessed and removed before coating.
See also: Galvanised Steel; Surface Preparation