Acrylic render
Acrylic render is an external wall covering made from acrylic or silicone-based materials, usually available in several different colours.
Adhesive mortar
Adhesive mortar is a low-slip mortar that bonds to a substrate or surface and can be used as a bed to mount a bead onto. Adhesive mortar can be applied to the surface in either a continuous line or in dabs and the bead pressed into place whilst the mortar is still wet.
Aggregate
Materials such as sand or crushed stone used in render and plaster.
Angle bead
Also known as a corner bead, this provides a straight finish to the render at an external corner whether within a window or door reveal, or at the extremities of a building. PVCu angle beads provide protection from impact and are shock resistant and reduce damage to the render, especially in high traffic areas.
APU bead
A time saving self-sealing bead for use around a reveal. APU beads have a mesh wing, a foot to receive render and on the underside of the foot a self-adhesive foam strip that is pushed up against the frame. APU beads will commonly have a self-adhesive tear off strip that allows protective sheets to temporarily cover the reveal while render is applied.
Arris
The sharp edge or ridge formed by two surfaces meeting at an angle.
Ashlar
Ashlar is a groove detail cut into a rendered surface to give the appearance of this traditional detail in stonework.
Backing
Backing is the substrate or surface that the first coat of render is applied to in timber frame and steel frame construction methods.
Base coat
The first layer of render or plaster applied to a surface.
Bead
A bead is a strip of material or trim made from PVCu, metal or wood and used in wall or surface finishing processes such as rendering and plastering to create an edge.
Beading
Strips of material or trims made from PVCu, metal or wood that are used in wall or surface finishing processes such as rendering and plastering are known as beading.
Bedding
Bedding describes the pressing a of bead into an adhesive mortar or plaster.
Bellcast
A bellcast is a thickening concave layer of render that is wider at the bottom than at the top like the profile found at the base of a bell. Usually created at the base of a wall above the damp-proof course or above windows to deflect water away from the surface it is applied to.
Bellcast bead
A bellcast bead helps form the bellcast in the render and provides a drip line for rainwater so that it does not return to the wall.
Bond
The joining of two or more surfaces or materials together.
Bonding material
Bonding material is used to join two or more surfaces or materials together when they do not bond well themselves, like mineral render on old brickwork.
Bridging
Bridging is the connection from one surface to another. An example of bridging is the insertion of a mechanical fixing through a bead and into a substrate. Although the substrate and any render placed over the bead are separated by the bead, the two items are connected by the bridging created by the mechanical fixing allowing heat transfer.
Build up
Build up describes the adding of one layer on top of another to create a consistent level surface.
Butt joints
A butt joint is where one bead is butted up against another. For example where a corner bead meets a bellcast bead at the base of an external wall. Note: Butt joints should always be sealed using something like PVC Pipe Weld.
Carbonation
Carbonation is the description of lime setting or going off where the chemical reaction completes its cycle of hardening.
Cavity
A cavity in the external curtain of a building is the gap between an inner and outer wall.
Cement
Cement is a mixture made of burnt limestone and clay that when mixed with water hardens and bonds aggregates together. It is the bonding agent in sand and cement render.
Cement plaster
Cement plaster is a mixture of sand and cement that is often used as a base coat for wall coatings like plaster.
Concrete
Concrete is material used in construction that is made from cement and aggregates such as gravel, sand, water and hardening compounds, usually cement.
Control joint
A control joint is a bead designed to cover two surfaces at a gap or joint and offers controlled expansion and contraction between the two surfaces in line with the expansion and contraction of the construction.
Corner bead
A corner bead is bead placed on a corner to give a reinforced straight finish.
Crazing
Crazing describes the narrow, fine cracks and lines that appear on a rendered surface or in plaster finishes. It is usually caused by poor surface preparation or using incorrect materials.
Curing
Curing is a term that describes a reaction, such as evaporation, taking place in a moist render that leaves it hard and permanent.
Damp proof course
A damp proof course is a waterproof layer in the construction of a floor extending into an exterior wall that prevents damp from within the ground, surface water or splashback from rain from entering into the structure. This should never be rendered over.
Dash
Dash is an aggregate such as crushed stone or pebbles that is embedded into a pre-hardened render to create a textured finish. Dry dash is added to the surface of the render.
DPC
A DPC or damp proof course is a waterproof layer in the construction of a floor extending into an exterior wall that prevents damp from within the ground, surface water or splashback from rain from entering into the structure. This should never be rendered over.
Drip bead
A drip bead is a bead with a sloping profile that assists the forming of concave bellcasts. Using a bellcast bead is a quick to apply process that gives uniformity and reinforcement to the bellcast and provides a drip line to prevent water returning to the wall.
Dry lining
Dry lining is both a description and a process where plasterboards or panels are fixed to frames to form internal walls. In the UK it is often finished with skim plaster.
Dry lining bead
A dry lining bead is a bead or trim that is used to finish or edge plasterboard or an internal panel and accepts a thin plaster coating.
Dubbing out
Where a substrate like a concrete block wall is irregular, it is dubbed out with cheaper mortar to make it level before the render is applied.
Edge beads
Edge beads are designed to finish edges on plasterboard and panels used internally. They butt up to the edge of the board or panel and provide a lip for skimming to give a sealed, clean, straight and finished edge.
EIFS
EIFS is short for Exterior Insulation and Finishing Systems. These are complete systems often comprising of several materials, layers or proprietary products that finish and insulate external walls.
Elastomeric coating
Elastomeric coating is usually an acrylic or pliolite based external wall covering such as a thin coat render or paint that makes a decorative, flexible and waterproof coating.
ETICS
ETICS is the abbreviation used for External Thermal Insulation Composite Systems. Multi-component insulation systems designed to improve the energy efficiency of new and existing buildings.
EWI
EWI is short for External Wall Insulation. A term usually given to complete insulation systems created by manufacturers of wall insulation products. But the term can also be applied to external wall coverings such as render.
Expansion bead
Also known as an expansion joint bead, this allows for the thermal expansion and contraction of the wall coating to help prevent cracking.
External curtain
The external curtain of a building refers to the external walls that form the perimeter of a building.
Facade
A facade is the exterior facing wall elements of a construction.
Fibreglass mesh
Fiberglass mesh is a woven fabric made from glass fibres covered in alkali resistant resin, used for reinforcement, crack prevention, and structural durability in render, especially over insulation boards.
Finish plaster
Finish plaster is a thin topcoat or skim of hard forming plaster that when gone off has a finish that is ready for decorating.
Finishing
Finishing is the name applied to the material used in the last treatment or coating of a surface. For example a finishing render is the top coat that may contain a colour or texture.
Float coat
A float coat is another term for a base coat. The first layer of material applied to a surface.
Friable
Friable is a term applied when a rendered surface becomes loose or flaky. This is often caused by poor preparation or using incorrectly mixed materials.
Grained render
Grained render is a silicone based top coat used externally to give a textured water-resistant finish.
Green
Green is a term often applied to render or plaster that is in the process of going off. It will have hardened but will not be fully dried.
Harling
Harling is a Scots term for a rough cast external render finish.
Heavy render
Heavy render is a term that can be applied to deep applications of sand and cement-based renders usually in excess of 20mm in depth.
Hexagonal holes
All genuine Renderplas beads have hexagonal holes stamped out of their wings. The hexagon is used as it is one of nature’s strongest engineering shapes and allows Renderplas beads to combine great strength with lightness and an unimpeded means by which the bead can be set into adhesive mortar or base coats.
HS codes for Renderplas beads
The HS code of Renderplas PVC beads is 39259010 (plastic profiles) or if they have glass fibre reinforcement mesh bonded to them 70195900 (plastic profiles with glass fibre mesh).
Insulated boards
Insulated boards can be applied to internal or external walls to add to the thermal performance of a building. Employed with PVCu beads and an insulating render or plaster, they can dramatically reduce the amount of energy used during the lifespan of a building.
Internal beads
Internal beads are sometimes referred to generally as plaster beads, but they can also include clip-on edge beads and shadow gap beads.
Ivory beads
Ivory beads are made by Renderplas from recycled PVCu and offer an excellent colour match to many natural shades of render and external paint.
J bead
J bead is a term sometimes used to describe a stop bead.
K Rend
K Rend is a manufacturer of prepared dry bagged exterior renders available in a range of colours. With 9 natural colours, Renderplas PVCu beads are an ideal partner to complement K Rend products perfectly.
Key
A key is a surface that has been prepared to accept render or plaster where the natural surface is unable or unlikely to form an effective bond with the render or plaster once applied.
Lath
Lath is the name given to thin narrow strips of material that form a lattice work. Used to provide a prepared uniform surface or key for render or plaster. Lath can be made from materials such as fibreglass or metal and in such forms is often referred to as mesh.
Masonry
Masonry is the name given to concrete, brick, concrete block, or stone substrates, or a combination of these materials.
Mesh
Wire mesh helps form smooth curved surfaces whilst glass fibre mesh reinforces render to prevent cracking, especially over insulation board.
Metal lath
Metal lath is thin lattice work made from metal. It is used as a keying surface for walls and ceilings where render or plaster is to be applied. Care should be taken when choosing metal lath over fibreglass lath as it can corrode and has the potential to degrade the surface applied on top of it over time.
Monocouche
Monocouche is a French brand of prepared and chemically constructed renders. Monocouche has also become a term in some areas to describe a pre-prepared render that is applied as a single coat. Monocouche renders are ideally paired with Renderplas PVCu beads as our colour combinations and thermal performance compliment them perfectly.
Movement joint
A movement joint is a bead designed to bridge two surfaces at a gap or joint that expands and contracts in line with the expansion and contraction of a construction preventing such movement from cracking any finish applied to the surfaces.
Nails
The BBA recommends that galvanised or stainless-steel fixings can be used to provide temporary support to assist in levelling the product but these should be removed before rendering. The PVC bead profile should be set on a bed of render instead.
Natural colours
There are many renders and paints for external wall application and Renderplas has created a range of 9 natural colours for its colour beads. All are designed to blend with the most popular and commonly used colours on the market.
One coat plaster
One coat plaster is a single coat plaster that can be used as an undercoat but goes off to form a finished surface that can be decorated without further preparation.
One coat render
One coat render is a pre-mixed render that can be applied directly to a solid substrate in a single coat up to 15mm.
Parex
Parex is a maker of prepared exterior renders that can be bought in a variety of colours. With 9 natural colours, Renderplas PVCu beads are an ideal partner to complement Parex render perfectly.
Parge coat
A parge coat is also known as a skim coat or decorative coat. A parge coat is a thin decorative application of render or plaster on a wall.
Pebble dash
Pebble dash is render finish where pebbles or aggregates with rounded edges are mixed into the render.
Pigments
Colour pigments are dry powdered materials that when mixed with render or plaster create a coloured finish.
Plaster
Plaster is material produced from gypsum that when applied to wall surfaces makes an ideal base for decorating and finishing.
Plaster bead
Plaster bead is the general term applied to beads used during the plastering process and are nearly always used for wall finishing interiors.
Plasterers bead
A plasterers bead is a traditional term for a plaster bead that is used to reinforce corners and edges when plastering.
Plasticity
Plasticity is a term that describes how easy a material is to shape and to mould.
PVA
PVA stands for polyvinyl acetate and is used as a multi-purpose bonding agent. It can sometimes be used for priming unsound surfaces prior to plastering or rendering.
PVC pipe weld
PVC pipe weld is an adhesive that can be used when joining more than one PVCu bead to another to form butt joints.
PVCu
PVCu is a is a thermoplastic polymer, unplasticised polyvinyl chloride and is commonly referred to as plastic or PVC. It is ideal as a material for render and plaster beads because it is durable, easily worked, does not allow thermal bridging and is sustainable. For example, the Renderplas range of white corner beads, stops and bellcasts are made from 100% recycled material.
Quirk
Usually found on a moulded corner, a quirk is an acute angled notch on either side of the moulding.
Quoin
A quoin is an external angle or corner of a building, or the stones that form them.
Render
Render is a material that is applied to an external wall. It is used to enhance the look of a building, how it weathers and it functions thermally. The materials used to make render can range from a simple sand and cement mixture to a chemically manufactured compound.
Render bead
Render bead is a general term applied to beads, whether these are PVCu or metal profiles, that are used to assist in the rendering process.
Rendering
Rendering is the process of applying render to an exterior wall.
Reveal
Where a wall meets a frame in the opening of a wall. Typically a window or door.
Rough cast
Rough cast is a technique for applying a top coat to a rendered surface to create a rough finish. A wetter slurry mix is added as a top coat to the base mortar and clean aggregate is thrown onto it.
Scat coat
A scat coat is a thin wetter slurry layer applied before the main layer of render to even out a rough surface and provide a better mechanical key for the scratch coat.
Scratch coat
A scratch coat is usually the first coat or render or plaster to be applied to a substrate and is scored to form a key or prepared bonding surface for a top coat or finish.
Scrim
Scrim is a mesh fabric made from materials such as fibreglass and is used between other materials to give reinforcement and stretch resistance. Scrim is often used in patches or repairs to rendered or plastered surfaces and used where non moving joints can be found.
Shadow gap
A vertical or horizontal linear recess feature on an internal wall. Often used around flush fitting doors and instead of skirting boards, a clean-cut linear recess is formed into the wall surface itself using a shadow gap bead clipped into plasterboard.
Skim bead
Skim bead is a general term for a bead with an arris of 2mm or less and used during the plastering process to help to strengthen and form regular edges and corners.
Skimming
Skimming describes the process of applying the top coat of plaster onto plasterboard and is done to create a smooth finished surface and cover the joints.
Spalling
Spalling describes render or plaster flaking or falling away in chips. It is usually caused by water ingress, where materials have been mixed incorrectly, poorly applied or the surface has not been properly prepared.
Spar dash
Spar dash is a render finish where aggregates with sharp edges are applied to the surface of the render when still wet and left to form a textured finish.
Stop bead
A Stop bead is a bead used to form a strong clean edge during rendering and plastering. Generally used around window and door openings, but is also used architecturally to help to form features in render and plaster or where render meets a brick finish.
Stucco
Stucco is a smooth render finish.
Tanking
Tanking is a coating that is applied to a wall to prevent moisture ingress.
Tape and joint
Tape and joint dry lining systems, or drywall in the USA, uses plasterboard that can be painted without the need for skim plaster, and only the joints are sealed with scrim tape and jointing compound.
Thermal bridge
A thermal bridge is created when a conductive material such as metal runs through insulating layers. An example of thermal bridging could be seen if you were to use a thermal imaging camera to view a rendered building where metal beads had been used. The image would highlight those areas where the heat is conducted from the inside to the outside via the thermal bridge created by the steel beads.
Thin coat bead
A thin coat bead is a bead with a small arris or shallow profile for use where a shallow render or plaster depth is required. Often used with acrylic or proprietary renders such as Weber, K-Rend or Monocouche.
Thin coat render
A thin coat render is a render that is often used as part of an external wall insulation system. Mainly made from silicone or acrylic materials, it is applied as a finishing render and is usually coloured, but some people refer to 10mm render coatings in this way.
Through colour render
A through colour render is an external wall coating that is ready prepared with a pigment that gives it a colour that does not need painting.
Top coat
A top coat is the final finishing layer of a multi layered wall coating.
Tyrolean
Tyrolean is a render finish that has a spattered appearance. The pattern is achieved by spraying the top coat onto the wall.
Undercoat plaster
Undercoat plaster is the first layer of plaster used to build up to the desired thickness of plaster before skimming.
Vermiculite
Vermiculite is a lightweight silicate aggregate used in insulating and acoustic render and plaster.
Voussoir
A voussoir is a wedge-shaped brick or stone. Several used together can form an arch under which you fix an arch bead to give a clean, strong and evenly curved edge to render or plaster up to.
Weber render
Weber is a maker of prepared exterior renders that can be bought in a variety of colours. With 9 natural colours, Renderplas PVCu beads are an ideal partner to complement Weber render perfectly.
Xella board
Xella board was associated with Fermacell gypsum fibreboard used in drylining wall systems to offer extra sound insulation and strength. They split from Fermacell which was bought by James Hardie and Xella is now part of Holcim.
Y-shape design
Corner beads with a Y-shape profile give an extremely narrow arris and maximise render thickness at the most vulnerable point, increasing strength. This was invented by Renderplas in 1991.
Zoophorus
A zoophorus is an architectural feature; usually a frieze between the architrave and cornice decorated with animal or human figures on a raised plaster area which can be formed using stop beads.