TECHNICAL GLOSSARY & TERMS FOR PLASTERING, RENDERING & REPAIR TRADES
ACRYLIC FINISHES
Top coat and through colour renders are often thin acrylic or silicone based materials that can be trowel or
spray applied
AAC
Autoclaved Aerated Concrete is a lightweight, precast building material; it provides structure, insulation, fire
and mould resistance in a single material. AAC products include blocks, wall, floor and roof panels
ACCELERATOR
An admixture added to render, plaster or mortar which speeds up the natural set
ADHESION
The bond between two coats or to a backing or substrate
ADMIX
An additive substance added to a cement based mortar or concrete to improve or modify its performance. This
material make more flowable or pumpable, more flexible or hard, more waterproof or frostproof
AGGREGATE
Sand particles or crushed stone that form the bulk of a mortar or render mix
AIR ENTRAINMENT
The introduction of minute air particles that are introduced with the aid of an air entraining admix during mixing
ALPINE FINISH
Alpine finish is a white cement based mix containing aggregates that provides a decorative finish looking like
dragged travertine. It is traditionally seen in Alpine resorts and was common in the 1970’s and 80’s but seldom
used now on new build
ANGLE BEAD
A metal or plastic angled trim used to reinforce external corners
ARRIS
A sharp external angle, usually 90 degrees, where two faces meet; an arris may be bevelled, rounded,
chamfered, radiused or splayed
ARTEX
Gypsum based textured coating commonly used for a stipple finish on ceilings. Artex produced before 1985
contained a small percentage of asbestos. A risk assessment should be undertaken before removing textured
coatings from properties built before this time
ASBESTOS
A magnesium silicate mineral that was used extensively in construction up to the mid 1980s. It offered
resistance to heat, electricity and chemical damage, good sound absorption and tensile strength. Asbestos
materials in good condition are safe unless asbestos fibres become airborne through damage or repair work.
Inhaling asbestos fibres increases the chance of getting asbestos related disease including mesothelioma, lung
cancer or asbestosis
ASHLAR
Relief detail cut into render to give the appearance of masonry
BACKING
The material or substrate to which the first coat of rendering is applied
BARK TEXTURE COATING
A dragged vertical stipple used as an all purpose external coating to cover and renovate brick and masonry.
Still used for external renovation but this finish is now best kept for use on Portacabins
BEDDING
Setting a bead with wet mortar or plaster
BINDER
A component that hardens to bind aggregates together; normally lime or Portland cement
BOND
The interface strength resulting from adhesion or a mechanical key
BONDING
An undercoat plaster for low suction backgrounds including concrete and plasterboard; this material has a
sticky feel
BROWNING
Undercoat plaster made from gypsum plaster and sand; now increasingly replaced by pre-mixed lightweight
plasters including hardwall
BUCKET TROWEL
Square end gauging trowel for scooping material from the mix bucket and dabbing on the wall surface
BUILD UP
Several layers of products, from substrate to finish
BUTTER COAT
The soft final coat to which the aggregate is applied in dry dashing
CARBONATION
Carbonation refers to the process of a hydraulic lime setting or going off, completing the chemical return of the
hydroxide of lime hardening back to calcium carbonate
CAVITY
The space between the inner and outer leaf of your wall construction
CEMENT
This is now commonly understood to be Portland cement, so called because it resembles Portland stone when
set. It is produced from burnt limestone and clay and then crushed and fired at higher temperatures to produce
a very reactive material. When mixed with water it hardens in a process known as hydration to form a paste
binding the aggregate particles to form a mortar. Cement is the basis for concrete, a mixture usually comprised
of cement, water and the addition of gravel
CEMENT PLASTER
A cement and sand mix is traditionally used as a backing or float coat. The mix for a backing coat should be 4:1
sharp sand to cement; this can be varied depending on the background
CLOSE IN
The action of consolidating with a trowel or float the plaster or render surface
COMPRESSOR
Electric, petrol or diesel powered machine, providing compressed air to operate spray guns, pumps and air tools
CONCRETE
Concrete is a construction material composed of cement, aggregates including coarse gravel and fine sand,
water and admixtures. Concrete solidifies and hardens after mixing with water and placement due to a chemical
process known as hydration. The water reacts with the cement, which bonds the other components together,
eventually creating a stone like material. Concrete is used more than any other man-made material in the
world; about 7 cubic kilometres of concrete are made each year, more than one cubic metre for every person in
the world
CONTINUOUS MIXER
A hopper feed mixing machine that will consistently mix plaster and mortar with water to supply a spot board,
tub or pump. The bagged material is fed into the hopper and water is gauged and metered continuously
CORNER TROWEL
Angled stainless steel trowel used to form and finish corners or arrises; can be internal or external
CRAZING
The fine cracks that develop on a surface usually caused by using an incorrect mix or poor surface preparation
CURING
The process when a cementitious material goes off with evaporation; the process is called hydration
DAMP PROOFING
This is a protective measure applying a waterproof material to the exterior foundation wall to prevent damp
DARBY
Aluminium rule with handles for levelling plaster and render
DASH
Dry dash is an angular aggregate thrown, cast or harled onto a wet butter coat render, leaving an exposed
aggregate finish, which is then tamped in with a float
DAUB
This is traditional mixture of clay and chopped straw used in wattle and daub. Wattle is the strips of wood
formed as slatted panels. Daub is the roughly applied course material that makes a good first coat onto straw
bale before subsequent coats of lime plaster
DENSITY
Density is the relationship between a material weight (kg) and its volume (ltr). In metric terms it is measured
in kilogrammes per cubic metre (kg/m3). It is the mass of particulates, granular materials or powdered solids
divided by the volume they occupy including the voids between the particles. Water has a density of 1.0,
cement mortar 2.16 and plaster 0.85 kilogrammes per cubic metre (kg/m3).
DPC
A Damp Proof Course is a horizontal barrier in a wall designed to prevent moisture rising through the structure
by capillary action, a phenomenon known as rising damp. A damp proof course can be a strip of bitumen placed
in the masonry during building or an injected penetrating chemical
DPM
Damp Proof Membrane performs a similar function as a DPC for a solid floor
DRY LINING
Also termed as drywalling, it is application of fixing plasterboard on timber or metal frames to create internal
walls or adhering plasterboard to blockwork walls, with plaster adhesive dabs
DUBBING
To bring the surface, usually hollows, out to a desired level
EFFLORESCENCE
Salt residue migrating to the surface of a render finish, through evaporation or hydrostatic pressure
EIFS
Exterior Insulation and Finish Systems are a range of building products that provide exterior walls with an
insulated finished surface and waterproofing in an integrated composite material system
ELASTOMERIC COATING
High build, acrylic or pliolite based wall external paint, that provides a flexible, waterproofing, decorative and
protective coating. An elastomeric coating seals out external moisture, but water vapour from within a masonry
surface can escape through it without blistering
EML
Expanded Metal Lath is a metal mesh that provides a base or key for finishing materials including plaster and
render; it can be fixed to masonry, suspended ceilings and timber frames, and used to form a flat or curved
surfaces
EPS
Expanded Polystyrene is a foam material usually white and made by expanding polystyrene plastic beads. It is
used in construction, external wall insulation, for void formers and packaging. The material is produced in
various board and panel sizes and block shapes; it is lightweight, easily shaped, and offers good thermal
insulation
EWI
External Wall Insulation is a system that involves the fixing of insulation boards to the outside of a building,
which is then covered with a mesh reinforcement, a base coat and a final decorative render finish. This layered
method encases the property and helps prevent heat from escaping from the property
EXPANSION BEAD
A material bead used at as a joint to allow small movement between different sections of masonry, concrete or
slabs
FACADE
Frontage or exterior walls of a building; often the part of the building given the most attention architecturally
and cosmetically
FAT
Small grains that are brought to the surface when sponging plaster or floating render and concrete; these are
then trowelled back into the plaster to achieve a smooth surface
FEATHER EDGE
An aluminium straight edge used as a rule to level and smooth areas of plaster and render
FIBRES
Fibres are an alternative to animal hair and are used as a reinforcement in lime mortar and render mixes. The
man made fibres are easier to introduce into the material during the mixing stage requiring only a few minutes
mixing to be thoroughly distributed
FINISHING
The final stages of applying the plaster top coat. Once the skim plaster starts to harden, dampen the surface
using clean water and a waterbrush; go over the surface with a sponge float and close in with a stainless steel
spatula. Finally trowel and polish up for a smooth flat finish
FINISH PLASTER
A skim topcoat providing a hard trowelled surface that is ready for decorating. Finish plaster can be applied to a
range of internal backgrounds, including hardwall, plasterboard and sand and cement
FLOAT
Plastic or wooden faced hand trowel to rough finish plaster or render; leaves a floated, open finish
FLOAT COAT
Sand and cement mortar mix used as an internal backing coat or external render; usually has a sand finish
FORCED ACTION MIXER
Paddle mixer machine that generates a thorough and consistent mix action ensuring homogeneity of materials
particularly where the components are not readily miscible. These mixers include rotating paddles that turn and
fold the material
FREEFALL MIXER
A freefall mixer is a machine with a revolving and tipping drum for discharge into a barrow or tub. This mixer is
commonly called a cement or concrete mixer and will combine cement, aggregate such as sand or gravel, and
water to form concrete or mortar
FRIABLE
Soft, loose or flaky render or concrete, often caused by incorrect mixing or gauging
GRAINED RENDER
A silicone based top coat render designed for external use, with a 3mm grain size finished in a dragged texture,
offering a high level of water resistance and flexibility
GREEN
The application or material has set, but is still wet
GROUT
Grout is a construction material, a mixture of cement and other fine material such as fine sand used to embed
rebars in masonry walls, cement sections of concrete, fill voids, and seal joints. Grout is composed of a mixture
of water, cement, sand and is applied as a thick liquid which hardens
GYPSUM PLASTER
Gypsum is a solid white naturally occurring mineral, the main constituent of which is calcium sulphate. Modern
plaster is produced from gypsum with lightweight aggregates and a retarder. It is unsuitable for external work
or wet areas
HAIRED LIME MORTAR
Animal hair is added to the lime mortar mix to achieve greater tensile strength and to minimise shrinking and
cracking. It is also used when plastering or rendering onto laths and onto solid backgrounds including cob,
stone or brick. The hair has to be worked into the final mix
HARDWALL
Backing coat gypsum plaster used as a replacement for sand and cement float coat
HARLING TROWEL
A square slightly curved hand tool that is used for applying and flicking decorative aggregative, dash and
pebbles onto the final butter coat. Also used for throwing wet top coats with course aggregates
HELIX MIXER
A type of mixer paddle consisting of two or more narrow spiral ribbons, affixed to the mixer shaft. Helix or
spiral mixes are the best all round paddles for mixing plaster, render and mortar
HOMOGENOUS
Elements mixed evenly to make a single substance. Homogenization is a process for the intensive mixing of
materials to obtain a mixture that is the same throughout the entire substance
HYDRATED LIME
Hydrated lime, also know as slaked lime, is quicklime, slaked with water.
It may be in the form of a dry powder or if combined with a greater quantity of water during slaking, in the
form of putty. Commercial hydrated lime is available from merchants and used as a plasticiser in cement. Do
not confuse 'hydraulic' and 'hydrated' lime
HYDRATION
Hydration refers to the chemical process of Portland cement setting or going off when combined with water and
aggregate, hardening into concrete or mortar. The cement reacts with water to form a paste that coats and
binds the aggregate to form a solid mass
HYDRAULIC LIME
Hydraulic lime is made from limestone that contains such as clay and the set is caused by these impurities
within the original lime source, in effect a naturally occurring additive. Unlike non-hydraulic lime it can set in
the absence of air and also under water, hence the term hydraulic. The more hydraulic a lime is, the greater its
strength but it is less permeable and flexible. Hydraulic limes are sometimes referred to as "water limes".
Hydraulic lime is normally supplied as a pre-bagged powder and requires mixing with sand on site. It cures
much faster than non-hydraulic and is used in repair and new build projects
IMPELLOR
The portion of the agitator imparting force to the material being mixed
KEY
Prepare a surface to receive a of plaster or render. The roughness of the surface enables the next coat to make
a mechanical bond
KNOCKING UP
The process of re-working lime mortar, normally in a roller pan mixer, to a stage when it is suitable for use. It
is not always necessary to add water; when it is added, it should not affect the quality of the mix
LATH
Strips of wood that were often found in traditional buildings. They are pinned in place to form a slatted base
onto which a lime plaster can be applied
LIGHTWEIGHT PLASTER
Plaster with lightweight aggregates including expanded perlite combined with retarded hemihydrate plaster; it
has low shrinkage and is thermally insulating
LIME PUTTY
Also termed as fat lime, this traditional building material is quicklime slaked with water and left to mature for
three months to thicken and form a soft buttery mixture with the consistency of toothpaste, pure white in
colour. The resulting fat lime putty is also known as non-hydraulic lime because it requires exposure to air to
carbonate and does not set under water. This lime is often regarded as the best lime to use in the conservation
of old buildings where it is important to maximise softness, breathability and flexibility. Fat lime putty is
supplied to site covered by a thin film of water in air tight tubs and mixed with aggregate to produce plasters,
renders and mortars
LIMEWASH
Limewash is made by diluting lime putty with water and is used as an external paint or protective coating. It is
usually white, hence white wash; pigments can be added to form a colour wash. It sets when exposed to
carbon dioxide in the air. It is the ideal paint to use on lime render and plaster, softer masonry and brick as it is
a breathable paint. It has a matt finish and a depth which most modern paints lack as it reflects sunlight
MASONRY
A substrate consisting of concrete, brick, concrete block, or stone
MEGAMIXER
The best selling paddle mixer, made in Germany by Eibenstock Power Tools and marketed by Refina.
Megamixers sold in the mid 1980’s are still working on site and being serviced by Refina
METAL LATH
Sheets of metal mesh, used as a plaster base for walls and ceilings; they may also be used as a reinforcement
over other forms of plaster base
MIXER PUMP
A screw pump for mixing and spray applying plasters and renders than are suitable for mechanical application.
These machines are normally require a three phase electrical supply
MIXING
The mechanical process of stirring or blending two or more miscible components, to produce a homogeneous
material and a more uniform mass
MONOCOUCHE
Monocouche renders are a type of decorative finish applied to the outside of buildings and facades to provide
both decoration and weather protection. The French term monocouche is used to differentiate modern polymer,
silicone and acrylic based renders from traditional cement or lime renders. They are more advanced render
formulations that can be applied in one coat to form and cure as one monolithic layer on the elevation of a
building
MORTAR
Mortar is a mixture of sand, a binder such as cement or lime, and water and is applied as a paste which then
sets hard. It is used primarily for bedding, bonding and pointing stone, brick, blockwork, and laying floor tiles;
also used as undercoats for plaster and render. It was introduced in the nineteenth century to develop stronger
mortars and soon superceded lime mortar for new construction as it sets harder and quicker, allowing a faster
pace of construction
MORTAR GUN
Hand or air powered gun for applying repair and pointing mortars
MULTI FINISH
A skim coat finish plaster applied over a backing coat, hardwall, browning or plasterboard and normally about
2mm thick. It requires damping down, sponging and final trowelling up to get a smooth final finish
NHL
Natural Hydraulic Lime is produced from limestone containing clay or other silica impurities. There are three
grades NHL 2 (feebly hydraulic), NHL 3.5 (moderately hydraulic) and NHL 5 (eminently hydraulic). The more
hydraulic a lime, the greater its strength but it is less permeable and flexible
NON-HYDRAULIC LIME
Non-hydraulic limes are produced from pure limestone without clay or silica impurities. Non-hydraulic lime can
only achieve a set through carbonation, combining with the carbon dioxide in the atmosphere. They are
sometimes referred to as "air limes" or traditional lime and used mostly in the restoration of historic buildings
and conservation work. Non-hydraulic lime is slow setting and is good for internal plasterwork or for use on soft
backgrounds
ONE COAT PLASTER
A single coat universal undercoat and finish plaster that can be trowel or pump applied. It suitable for a range
of internal surfaces, including brick, blockwork, plasterboard and concrete
PADDLE MIXER
Mixer drill and paddle for whisking plaster, render, lime, mortar, screed and epoxy
PAINT
Paint is the general term for decorative and protective coatings used to coat and add colour to a surface by
covering it with a pigmented film. There are three primary components to a paint, a binder, dilutent, and
additives. Pigments are among the most common additives as they give a colour to a paint. Typical binders
include synthetic or natural resins, acrylics, polyurethanes, polyesters, melamines, epoxy or oils
PARGE COAT
A thin application of plaster for coating a wall
PARGETING
Pargeting is the application of a decorative pattern or relief to external render. On half-timbered houses, the
term is usually refers to the decoration of the render between the studwork. It can also refer to the indented
deep pattern created with a trowel onto the render
PEBBLE DASH
A dry dash finish in which pebbles or rounded aggregates are pushed into wet render and left exposed. Spar
dash is a similar but sharp or angular aggregate is used
PERIPHERAL SPEED
Shaft and spindle speed is measured in revolutions per minute (rpm). The main mixing action is generated at
the tip of the mixer paddle; the larger the mixer paddle the faster the peripheral speed of the impellor tip
PERLITE
Perlite is a natural siliceous volcanic rock and when heated it pops in a similar manner to popcorn. Expanded
perlite is lightweight and has outstanding insulating characteristics. It can be used as an aggregate in cement
renders and gypsum plasters, for the fire protection of beams and columns, under-floor insulation, as a loosefill
in masonry construction, paint texturing, gypsum boards, ceiling tiles and roof insulation boards
PICK UP
Point at which the product begins to set
PIGMENTS
A powdered solid for colouring other materials including paint, cement and mortar
PLASTER
Plaster is a building material produced from gypsum. When dry plaster powder is mixed with water it can be
trowel or spray applied to wall surfaces. Unlike cement, plaster remains quite soft after drying, making it
suitable for a finishing rather than as a load-bearing material. Smoother than render, usually termed for
internal work
PLASTERING
The trowel or spray application of a gypsum plaster for interior wall finishing and coating
PLASTIC TROWEL
Lightweight plastic trowel for finishing render top coats
PLASTICITY
Refers to the softness of plaster, render or mortar, and how easy it is to mould and shape. Plaster with a high
plasticity flows easily and is easy to work with. When a material is ‘plastic’ it can be moulded and formed;
when it loses its plasticity it becomes hard and can no longer be worked
POINTING
Fillets of mortar to fill the gaps between stone, block or brick in walls; also refers to the joints in floor slabs,
tiles and granite sets
POLISHED PLASTER
A decorative internal finish also known as Venetian, Marmorino or marbled plaster. It can be smooth, shiny and
marble like or textured to look like stone. Venetian plaster is made from lime putty and marble dust and applied
in thin coats up to an overall thickness of 1mm. Marmorino plaster uses a blend of coarser marble dusts and is
applied in thicker coats up to 2mm and can be trowel finished or textured
POOL TROWEL
Flexible steel trowel with rounded ends for finishing curved wall surfaces
POZZOLANO
A volcanic silica dust when mixed with lime, sets hard making Roman cement. The term pozzolanic additive
now includes other aggregates such as pulverized fuel ash and brick dust
POWER FLOAT
Hand held power tool for floating and sponging plaster and render; can be used for scratching a render before
the final set
PREPARATION
Plaster and render require a clean, dust free and keyed surface to ensure a good bond. Mechanically prep the
surface to remove any loose residues or contaminants. To ensure good adhesion, dampen the surface just
before plastering
PROJECTION
Spray pump application of plasters and renders that are produced for mechanical application; as a rule the
material should be formulated for the pump rather than the equipment engineered for the material
PROJECTION PLASTER
A one coat plaster for mechanical application by a spray pump
PVA
Polyvinyl Acetate is a multi-purpose bonding agent, primer, sealer, cement and plaster admixture that adheres
to most building materials. Ideal for priming unsound surfaces prior to plastering or painting, also applications
where one surface is porous
QUICK LIME
Quick lime, also known as lump lime, is produced from heating calcium carbonate limestone or chalk. This is
the raw material before it has been slaked with water to make hydrated lime
QUOIN
An external corner of a building or a cornerstone
RENDER
A wall coating of lime, cement or polymer mortar. Render is a material made of an aggregate, binder (cement
or lime) and water which is applied wet, and hardens to finish the exterior, often the façade or front of
buildings. In Europe the term stucco is commonly used. Render may be used to weatherproof and finish
external structures or cover visually unappealing construction materials such as concrete, block or damaged
brick or masonry. It is also used to finish external insulation
RENDER SPRAY GUN
Air powered hopper spray gun used to apply renders, lime mortars and fine roughcast
RENDERING
The application of cement or lime based mortar undercoats and finishing coats for external walls
ROUGH CAST
Rough cast or scat coat, describes a manual technique of applying a render top coat by harling, casting or a
runny cement mix with spar dash, medium or coarse aggregates, onto an external wall. It creates a rough,
spattered textured finish. The rough cast finish increases the surface area of the building wall and improves its
weatherproofing qualities helping avoid water penetration problems
RENOVATING PLASTER
Material used to recoat a range of internal wall surfaces
RETARDER
Added to cement, plaster or mortar to slow down the initial rate of setting by inhibiting hydration
ROLLER PAN MIXER
Forced action mixer that uses two rotating roller or milling drums to squeeze, work and mix the material; for
mixing lime mortars, putties, hair filled plasters and reworking old mortars and cements
SAND
Coarse sand, also known as sharp sand, is an angular grain aggregate; it crunches in the hand if compressed.
In use it should be should be a washed and free of vegetable matter, clay and salts. Soft sand has finer grains
and is used in mortar mixes for pointing and filling cracks. Silver sand makes for a lighter coloured mortar
SBR
Styro Butane Rubber is a liquid used as a primer and admix
SCABBLER
Power tool using rotating cutters to key, prep and key a wall or floor surface. The tool is recommended for
cleaning paint off render and concrete, and keying the surface before recoating
SCAT COAT
Another term for rough cast, a manual technique of applying a render top coat by harling, casting or a runny
cement mix with spar dash, medium or coarse aggregates, onto an external wall
SCRATCH COAT
The first backing coat of plaster or render, which is scratched or scored to form a bond for the second coat
SCRATCH FINISH
A render that is finished with a nail float to achieve an open grain texture
SCRATCHER
Comb or scraper used to key the base coat of plaster or render
SCREED
Floor screeds are an in-situ flooring of cement mortar laid to an accurate flat surface by screeding, or by selflevelling,
usually as the base for a separate floor finish or topping
SCREW PUMP
A pump using a metal pig tail type rotor and rubber stator; the screw pump is the most efficient for applying a
wide range of plasters and renders
SCRIM
A mesh fabric that is used as a membrane sandwich between other material to provide reinforcement and
stretch resistance; primarily used in plasterboard joints and patch repair
SKIMMING
Final coat of smooth plaster; also known as setting
SLAKED LIME
Also known as hydrated lime, it is quicklime, slaked with water. It may be in the form of a dry powder or if
combined with a greater quantity of water during slaking, in the form of putty. Commercial hydrated lime is
available from merchants and used as a plasticiser in cement. Do not confuse 'hydraulic' and 'hydrated' lime
SOLIDS WETTING
Dispersing solid particles so that a liquid film coats each particle. A solid suspension or slurry is a thick
suspension of solids in a liquid
SOUND
Free from damage and injury
SPALLING
The chipping or flaking of concrete, render or masonry caused by improper water ingress and drainage, poor
material production or application
SPATTER DASH
A wet sand and cement mix, flicked or sprayed onto the wall surface
SPATULA
Long stainless steel hand tool similar to a wide blade taping knife; it is used to skim over the finish plaster just
before the final set
SPIRAL PADDLE
A helix type of mixer paddle consisting of two or more narrow ribbons which spiral around the paddle shaft.
Used for mixing plasters, renders and mortars
SPIRIT LEVEL
A spirit level or bubble level is an instrument designed to indicate whether a surface is level (horizontally) or
plumb (vertically)
SPONGE FLOAT
A plastic float with a sponge face. It is used to smooth imperfections from the finish plaster prior to settings.
After skimming, use the sponge float with a light application of water to raise the fat. The surface can then be
closed using a spatula or trowel
STRAIGHT EDGE
Aluminium box section rule, used for levelling plaster and render and tamping in drywall boards
STUCCO
Smooth rendering, originally lime and sand but now more commonly a cement mortar
SURFACE PREPARATION
In the construction trade this process involves the mechanical cleaning, stripping and cleaning of surfaces,
masonry and structures that are to be plastered, rendered, repaired or painted. The prep method required
varies according to the surface to be finished but good preparation is the key to a successful outcome of any
coating or refurbishment
TANKING
A coating applied to a wall surface to prevent penetrating moisture entering. Can be cementitious or proprietary
plastic membrane
TEXTURED COATING
Thick paint which may be applied by brush or spray and manipulated by brush or trowel to give various
patterns. The coatings are often elastomeric providing a flexible and weatherproof that will cover and renovate
older building exteriors. Finishes range from sand and fine texture, dragged bark, orange peel, stipple,
simulated acoustic and splatter
THISTLE
Range of finish and undercoat plasters produced by British Gypsum
THROUGH COLOUR RENDER
External render that is pre-coloured with no need to paint
TOP COAT
This is the final application of a two or three coat external rendering system. A thin coat is a silicone resin
material designed for a final render finish, with a 1.5mm grain size finished in a uniform texture, offering a high
level of water resistance and flexibility
TROWEL
Steel hand float for laying on and finishing plaster and render; most tradesmen these days will use a stainless
steel trowel that is rust free
TWIN PADDLE MIXER
Mixer drill with twin contra rotating paddles; ideal for mixing heavy mortars, lime putties and fibre filled
materials
TYROLEAN
A spattered textured top coat render being sprayed onto a wall with hand operated applicator gun or spray gun
UNDERCOAT PLASTER
A base coat used to build up a suitable thickness of plaster before skim finishing. Suitable for use on a wide
range of internal backgrounds, including brick, blockwork and most smooth or low-suction backgrounds
VERMICULITE
It is an hydrated magnesium aluminium silicate similar in its original state to mica. It is a lightweight aggregate
and used in insulating and acoustic plaster and render, fire protection construction materials, texturizers in
coatings, acoustic and intumescent paints, lightweight insulating concrete, floor and roof screeds
VIBRATION LEVELS
Hand-arm vibration is vibration transmitted during work processes into workers’ hands and arms. Vibration
levels are measured in metres per second and govern how long a hand held power mixer can be used.
Generally most mixers will have a vibration level under 2.5m/s which is the point where vibration levels need
monitoring
VISCOSITY
The measure of resistance of a fluid material to flow when a force is applied to it. A low viscosity material would
be like milk, a higher viscosity like double cream
VOLUME
Volume and capacity are sometimes distinguished, with capacity being used for how much a container can hold
(with contents measured commonly in litres), and volume being how much space an object displaces
(commonly measured in cubic metres). One litre is also slightly less than one imperial quart
WALL SANDER
Large disc sander for smoothing and prepping plaster walls and ceilings, drywall joints, paints and coatings
WATER TO CEMENT RATIO
The strength of a concrete mixture depends on the water cement ratio. Mixes have been identified in terms of
the ratio of cement to fine aggregate to coarse aggregate. For example, the ratio 1:2:4 refers to a mix which
consists of 1 part cement, 2 parts of sand and 4 parts gravel. Cement and water are the two chemically active
elements in concrete and when combined, form a paste or glue which coats and surrounds the particles of
aggregate and upon hardening binds the entire mass together; the more water added, the weaker the paste
WATERPROOFING
The process where a building component is made resistant to the passage of water or water vapour. Left
unchecked, water can seep into cracks in stucco, plaster, and masonry surfaces causing the understructure of a
building to deteriorate. Moisture in any form can find its way into cracks and openings, but wind driven rain is
able to penetrate even the finest cracks
WORKABLE
Refers to the plasticity of a plaster or render and affects the ease of working or applying the material