Resin Bound Knowledge Base
Resin Bound Knowledge Base
Additive – The resin component of a bound resin system can contain additives such as UV Stabilisers, thixotropes, adhesion promoters, surfactants and moisture scavengers.
Aggregate – Only specially washed, dried, dust-free decorative aggregates should be used with bound surfacing resins.
Alcor – A StarScape aggregate blend consisting of 75% Goodrich Quartz 2-5mm and 25% Upnor Pink 3-6mm.
Aliphatic - The word aliphatic refers to a type of isocyanate (the ‘B’ component) which is completely stable under UV light (sunlight) and will not discolour or degrade. StarScape ULTRA only uses 100% aliphatic isocyanate.
Alnwick Gold – A StarScape aggregate available in a 1-4mm size.
Ambient Temperature - The ambient temperature is the temperature of the air which can be vastly different from surface temperature. When the ambient temperature is below 5°C or exceeds 30°C it is often better to delay a resin bound surfacing installation and focus on preparation work.
Anti-slip – The friction of a resin bound surface can be increased with a scatter layer of crushed glass, fine sand or Aluminium Oxide (alumina).
Aquila - A StarScape aggregate blend consisting of 75% Corfe Quartz 2-5mm and 25% Alnwick Gold 1-4mm.
Aromatic - The word aromatic refers to a type of isocyanate (the ‘B’ component) which is not UV stable and as such will discolour and degrade in UV light. StarScape ULTRA does NOT contain any aromatic isocyanates.
Asphalt – Sometimes referred to as ‘blacktop’, asphalt is the term for what we (the British) often call bitumen or tarmacadam (trade name).
Auriga – A StarScape aggregate blend consisting of 75% Kendal Gold 2-5mm and 25% Elsdon Bronze 1-3mm.
Aurora – A StarScape aggregate blend consisting of 75% Norham Red 2-5mm & 25% Goodrich Quartz 1-3mm.
BALI – A trade association for landscape professionals (www.bali.org.uk).
Bamburgh gold – A StarScape aggregate available in 1-2mm and 2-5mm sizes.
Baron – Manufacturer and supplier of high-quality forced action mixers (www.baron-mixer.com/en/).
Base – Refers to the surfaces under a resin bound installation which are called the base-course, sub-base, and sub-grade.
Bitmac – The trade name for bitumen macadam which is usually referred to as tarmacadam although natural tar is rarely used and has been replaced with bitumen.
Blend – A combination of decorative aggregates which are combined to improve surface performance and provide varied colours and aesthetics.
Blooming – A whitening of a resin bound surface typically caused by excess water entering the uncured product which results in a urea reaction (iso and water) rather than a urethane reaction (iso and resin).
Bonded – A ‘coat and scatter’ resin surfacing system in which a thin layer of resin is applied to the pre-existing surface and covered with aggregate. Once cured the excess aggregate is removed resulting in an attractive, natural looking surface without the problems associated with a loose gravel surface.
Bound – A ‘trowel applied’ resin surfacing system in which aggregate is mixed with a clear resin and then applied as a screed to produce a glossy, highly decorative stone surface.
Capella – A StarScape aggregate blend consisting of 75% Odell Gold 2-5mm and 25% Yielden White 1-3mm.
Carina – A StarScape aggregate blend consisting of 75% Kendal Gold 2-5mm and 25% Yielden White 1-3mm.
Catalyst – A typically metal based compound that is incorporated into the resin component in order to make the system cure. The reaction caused by the catalyst is usually referred to as the ‘Front end’ cure.
Celeste – A StarScape aggregate blend consisting of 75% Yielden White 2-5mm and 25% Elsdon Bronze 1-3mm.
Chemical resistance – The ability of the completed resin surface to withstand contact with aggressive or corrosive substances such as oil, fuel, solvents and pesticides.
Concrete – A common base course material made from a mixture of stone or gravel, sand, cement, and water.
Corfe quartz – A StarScape aggregate available in 1-3mm and 2-5mm sizes.
Corvus – A StarScape aggregate blend consisting of 75% Lindisfarne Quartz 2-5mm & 25% Norham Red 1-3mm.
Coverage rate – The volume of material required to cover a specified area at a specified depth.
Cure – A series of chemical reactions which result in the system increasing in viscosity and ultimately hardening by the cross-linking of polymer chains.
Cut-out – A process in which an existing driveway has large slots cut through the surface in order to provide drainage.
Cygnus – A StarScape aggregate blend consisting of 75% Odell Gold 2-5mm and 25% Pendragon Blue 2-5mm.
Day joint – Positions where the resin bound surface has been finished on one day and will be carried on the next day. To avoid cracking day joints are often fitted with an expansion joint or incorporated into a design element.
Deflection – The deflection is the number of millimetres the cured system will bend before breaking. A hard base such as concrete will not require a high deflection however a softer bitumen base will require a higher deflection.
Dig out – A trade term used to describe a full installation in which the existing surface is removed and a new sub-base and base are installed.
Discolouration – A problem caused by using a non-UV stable resin system. UV stable products (such as StarScape ULTRA) use an aliphatic isocyanate whilst lower quality, non-UV stable systems use an aromatic isocyanate.
DOT – A sub-base material named after the Department of Transport (DOT) specification for granular sub-base materials. Also referred to as DTp or MOT (Ministry of Transport).
Draco – A StarScape aggregate blend consisting of 75% Norham Red 2-5mm and 25% Wark Gravel 3-6mm.
Dunster black – A StarScape aggregate available in 1-3mm and 2-5mm sizes.
Dural – Manufacturer and supplier of aluminium trims and expansion joints for resin surfacing applications (www.dural.co.uk).
Edging – A trade term used to describe decorative brick/stones and trim used to form a solid, decorative edge to a resin bound surface.
Elsdon bronze – A StarScape aggregate available in 1-3mm and 2-5mm sizes.
Expansion joint – Expansion joints are dividers that provide room for movement (expansion/contraction) in the resin bound surface. They are not typically used on a tarmacadam base but must always be used to mirror any expansion joints in a pre-existing sub-base.
Farnham flint – A StarScape aggregate available in a 2-5mm size.
Feathering – This is a trade term for keeping a rough working edge whilst installing the resin bound surface. Each mix should be ‘feathered’ into any adjoining mixes to avoid visible joint lines. This is particularly important when using a sledge or resin box to lay the resin screed.
FeRFA – FeRFA, the Resin Flooring Association, represents the leading manufacturers, contractors and associated companies involved in industrial and commercial resin flooring, screeding and surface preparation. (www.ferfa.org.uk)
Ferrous – This describes aggregate particles that have an iron content and may be susceptible to rusting. As the aggregate used is a natural product it is always a potential issue however some aggregates are far more susceptible than others. The StarScape Approved Aggregates document grades the iron content of each aggregate and blend.
Flint – Flint is a hard, sedimentary form of the mineral quartz and often used as a resin bound surfacing aggregate.
Forced action mixer – A forced action mixer is a pan mixer in which the paddles (blades) are driven through the mixture. Specifically developed for mixing dense materials they are more efficient and effective at mixing bound surfacing materials than a standard cement (drum) mixer.
Full install – A trade term used to describe a resin bound installation in which the existing surface is removed and a new sub-base and base are installed.
Geotextile – Often used to describe a membrane which can be installed between the sub-base and sub-grade (natural) in order to create a reinforcing/filtering layer.
Glass – Glass spheres, beads or crushed glass can be scattered onto the uncured surface of a resin bound installation to increase its anti-slip properties.
Goodrich quartz – A StarScape aggregate available in 1-3mm and 2-5mm sizes.
Granite – Granite is a common type of stone used in resin bound surfacing. Granites are predominantly white, pink, or grey in colour, depending on their mineralogy.
Grid – Gravel grids are a form of aggregate retention matting which consists of an interconnected lattice structure allowing aggregate to fill the voids. Any grid systems used with a resin bound surface should have a wall thickness greater than 3.5mm and a minimum height of 40mm.
Halcyon – A StarScape aggregate blend consisting of 75% Kendal Gold 2-5mm and 25% Norham Red 1-3mm.
Heaving – A type of base fault common on low quality tarmacadam bases in which expansion or tree roots cause the surface to raise or tear in isolated areas.
Helmsley – A StarScape aggregate available in a 3-6mm size.
High friction surfacing – Also known as anti-skid, these are resin bonded surface treatment systems that are composed of tough, abrasion-resistant aggregates bonded to the surface using a resin. The term is also used to describe the slip resistance of a resin bound surface.
Incline course – An incline course is a slope that directs water away from drains and watercourses to a natural soakaway such as a garden or lawn.
Indus – A StarScape aggregate blend consisting of 75% Pendragon Blue 2-5mm and 25% Lindisfarne Quartz 2-5mm.
Iron spotting – Decorative aggregates can contain trace amounts of iron which can result in iron spotting or ‘Rust Spotting’. Rust spotting is a small area (usually the size of a pound coin) on the surface of the cured resin which discolours to an orange/brown. Due to the natural properties of aggregate it is not possible to guarantee against oxidation.
Isocyanate – The isocyanate is an Organic compound which contains functional groups and is used as a component of a bound resin kit. Typically, the ‘B’ component, it can be supplied in three different forms. 100% Aliphatic (UVS) which is UV stable and used in StarScape ULTRA, Aromatic (NON-UV) which is not UV stable, discolours and can become brittle over time or an isocyanate blend (UVR) which uses stabilisers to delay the damage caused by UV light.
Izar – A StarScape aggregate blend consisting of 75% Helmsley 3-6mm and 25% Kendal Gold 1-2mm.
Jerry can – A flat-sided bottle/container for storing or transporting liquids, typically the ‘A’ or ‘Resin’ component of a bound surfacing kit.
Kinley – Supplier of trims and edging for resin surfacing applications (www.kinley.co.uk).
Kit – The kit consists of two parts referred to as components. The ‘A’ component (Part 1) is the resin supplied in a jerry can and the ‘B’ component is the isocyanate supplied in a white, plastic bucket.
Kendal gold – A StarScape aggregate available in 1-2mm and 2-5mm sizes.
Levelling – This term describes the process of using a spazzle or rake to spread the mixed resin bound material over the desired surface before it is compacted using a trowel.
Lindisfarne quartz – A StarScape aggregate available in 1-2mm and 2-5mm sizes.
Lyra – A StarScape aggregate blend consisting of 50% Wark Gravel 3-6mm and 50% Lindisfarne Quartz 1-2mm.
Macadam – A trade name for bitumen macadam which is usually referred to as tarmacadam although natural tar is rarely used and has been replaced with asphalt / bitumen.
Membrane – Often used to describe a geotextile material which can be installed between the sub-base and sub-grade (natural) in order to create a reinforcing/filtering layer.
Middleham silver – A StarScape aggregate available in 1-3mm and 2-5mm sizes.
Mimosa – A StarScape aggregate blend consisting of 50% Corfe Quartz 2-5mm & 50% Bamburgh Gold 1-2mm.
Minimum depth – This refers to the minimum depth of any given material or surface. The minimum depth must always be greater than the average depth and this should be taken into consideration when pricing or ordering materials.
Mixer – This refers to the specialised Forced Action Mixer used to mix the bound surfacing resin with the aggregates or the operator who has the task of ensuring each mix is timed and consistent.
Mixing area – A area in which the mixing of the resin and aggregates is completed. The mixing area should be covered with plastic sheeting, safely positioned away from non-trained staff and ideally covered with a temporary gazebo to protect the mixing from both direct sunlight and moisture contamination.
Mix ratio – This term is used to describe the quantities of both the resin components and the aggregate in a mix. The mix ratio for StarScape ULTRA is 3.15% of resin (‘A’ component) to 2.96% of isocyanate (‘B’ component) to 93.9% of aggregate.
Moisture – The term is used to describe small quantities of water which are present in the air (ambient) or the aggregates.
Morpeth green – A StarScape aggregate available in 1-3mm and 2-5mm sizes.
MOT – A sub-base material named after the Ministry of Transport (MOT) specification for granular sub-base materials. Also referred to as DTp or DOT (Department of Transport).
Natural – This term refers to the natural ground material on which a sub-base, base course and the surface course are installed.
Nebula – A StarScape aggregate blend consisting of 75% Goodrich Quartz 2-5mm and 25% Morpeth Green 1-3mm.
Norham red – A StarScape aggregate available in 1-3mm and 2-5mm sizes.
Nova – A StarScape aggregate blend consisting of 50% Norham Red 2-5mm, 25% Pendragon Blue 2-5mm and 25% Pendragon Blue 1-3mm.
Odell gold – A StarScape aggregate available in a 2-5mm size.
Open-graded – A term used to describe the matrix structure of a tarmacadam sub-base. An open graded sub-base allows water to pass through it and as such is porous.
Orion – A StarScape aggregate blend consisting of 75% Upnor Pink 3-6mm and 25% Middleham Silver 1-3mm.
Overlay – An Overlay describes an installation in which the resin bound surface is applied directly over a pre-existing base such as tarmacadam or concrete.
Oxidization – Trace amounts of iron can be found in some of the aggregate types used with a resin bound system and when these come in to contact with air and water, the iron can oxidise forming hydrated iron oxide particles which can manifest as dark brown patches known as rust spotting.
Pendragon blue – A StarScape aggregate available in 1-3mm and 2-5mm sizes.
Pen value – The Pen value refers to the penetration value of tarmacadam. This is the measured penetration depth of a 100g needle dropped onto the tarmacadam for 5 seconds at 25°C (tenths of a mm). Tarmacadam surfaces with a lower Pen value are harder and soften less when exposed to heat. The ideal Pen value for a tarmacadam base which is to receive a resin bound surface is between 70 to 100.
Permeable – The permeability refers to the capacity of a porous surface to allow water to pass through it. One of the key benefits to using StarScape ULTRA over other traditional paving options is that it is highly porous and allows for the free draining of rain water and incorporation into a SUDs compliant installation.
Perseus – A StarScape aggregate blend consisting of 75% Farnham Flint 2-5mm & 25% Morpeth Green 1-3mm.
Planning permission – It is possible to create a SuDS compliant surface using any type of paving however a resin bound surface offers a very simple, cost effective, decorative option. Regardless of SuDS compliance, replacing or covering an existing driveway or pathway with either a permeable surface or non-permeable surface which directs water away from drainage networks, will not typically require planning permission. More information regarding SuDS regulation and planning permission can be found on the government website: ●
Polished stone value – The Polished Stone Value (PSV) is typically a value used to describe slip resistance and is a measure of an aggregate’s resistance to the polishing action of vehicle tyres under conditions similar to those occurring on a road surface. The test is conducted using a portable skid resistance tester and measured using the standardised test (BS EN 13043).
Polyaspartic – The word polyaspartic refers to a type of resin (the ‘A’ component) which is used in conjunction with aliphatic isocyanates. Star Uretech have patented the use of this technology in resin bound surfacing and despite its very high-performance characteristics, the high costs currently prevent it from being a suitable replacement for polyurethane systems.
Polyurethane – When the two components of a bound surfacing kit are mixed together the resin component reacts with the isocyanate component to form a ‘polyurethane’ which is clear and has very strong, slightly flexible properties.
Polyurea – If the isocyanate component of a resin bound kit is allowed to react with water instead of the resin component this reaction will create a polyurea which is white and brittle.
Polaris – A StarScape aggregate blend consisting of 50% Goodrich Quartz 2-5mm & 50% Yielden White 1-3mm.
Porous – Porosity is the property of the resin surface that is an indication of the ability for water to flow through it. High porosity will allow water to pass rapidly through the surface and prevent the build-up of surface water whilst a low porosity will result in pooling and the potential for flooding.
Primer – A primer is a single component, low viscosity liquid product which is used to strengthen a sub-base and aid the adhesion between the bound surface and the sub-base. StarScape ULTRA has been specifically formulated to be self-priming and remove the need for a primer however, on concrete sub-bases which show signs of dusting (the surface continues to produce dust whilst sweeping) StarScape PRIMER can be used to resolve this.
Quartz – Quartz (SiO₂) is a very hard type of aggregate consisting of silica and oxygen. It is typically colourless or white hexagonal prisms or can be coloured by impurities.
Reflective Cracking – Reflective cracking is a result of differential movement between the resin bound surface and the sub-base. A low quality, damaged or expanding sub-base will often crack and as the resin bound surface is adhered to the base these cracks can be reflected in the resin bound surface.
Refusal – The term ‘Refusal’ is used to describe a level of compaction in which a material cannot be more compacted. A resin bound surface is hand trowelled and sufficient downwards force should be applied to the trowel so the aggregate is compacted to refusal.
Resin – The word ‘Resin’ is often used to describe the chemical components of a bound surface or the application as a whole ‘Resin Bound Surfacing’. The resin is actually one of the two chemical components (typically the ‘A’ component) that forms a resin bound surfacing kit and is a combination of polyols, additives and catalysts.
Rigel – A StarScape aggregate blend consisting of 75% Pendragon Blue 2-5mm & 25% Middleham Silver 1-3mm
RSMA – The Road Safety Markings Association is a trade association for companies involved with road safety markings and surfaces in the UK (www.rsma.co.uk).
Rust spotting – Rust spotting occurs when trace amounts of iron found in natural aggregates comes into contact with air and water. The iron can oxidise forming hydrated iron oxide particles which can manifest as dark brown patches known as rust spotting.
Scorpii – A StarScape aggregate blend consisting of 50% Norham Red 2-5mm & 50% Norham Red 1-3mm.
Screed – The term ‘screed’ is used to describe a levelled layer of material (e.g. a resin bound surface) applied to a sub-base or other surface.
Sirius – A StarScape aggregate blend consisting of 75% Yielden White 2-5mm & 25% Kendal Gold 1-2mm.
Skipsea slate – A StarScape aggregate available in a 1-3mm size.
Slope – Slopes are typically referred to as inclines. A resin bound surface is not suitable for inclines exceeding 30% (16.7⁰) and an incline greater than 10% (5.71⁰) must feature a Silex anti-slip finish to the resin bound surface.
Soak away – A soak-away is the term used for an area in which water can sufficiently drain naturally as opposed to being directed into the local watercourse through drains.
Sol – A StarScape aggregate blend consisting of 75% Corfe Quartz 2-5mm & 25% Yielden White 1-3mm.
Solvent – Solvents are used to clean tools, equipment or as a trowel lubricant. The types of solvents used in the resin bound surfacing industry are typically aromatic solvents which contain an aromatic hydrocarbon such as naphtha, toluene or xylene. Due to the nature and potential moisture content of some aromatic solvents they should never be used as diluents or left in contact with a cured resin surface.
Soroto – Manufacturer and supplier of forced action mixers (www.soroto.com).
Spazzle – A spazzle is an industrial rake designed for moving and levelling large amounts of aggregates, concrete, tarmac, and other loose materials. A spazzle will usually have rake like teeth whilst a lute will typically have a flat edge.
Specific gravity – The SG (specific gravity/relative density) is the ratio of the aggregate density (ρ) to the density of a reference substance and is required to calculate the coverage rates.
Stone carpet – Stone carpet is a generic term used to describe a resin bound surface however it is now commonly used to describe a low strength resin bound surface which is installed in areas that will receive no vehicular traffic such as showrooms, pool surrounds or internal flooring.
Sub-base – The sub-base is the MOT1/DTp1 surface installed above the natural ground (Sub-Grade) and below the tarmacadam/concrete (Base course).
Sub-grade – The sub-grade refers to the natural ground (soil/clays) on which the additional layers of a resin bound surface are installed.
SuDS – SuDS is an acronym for Sustainable Urban Drainage Systems. In urban areas many of the surfaces are sealed by paving and buildings which means that rain water has to be diverted to drainage networks. In heavy rainfall the drainage systems may be overwhelmed by the surface water and this can result in localised flooding. Sustainable urban Drainage Systems are designed to alleviate the problems by decreasing flow rates to watercourses and by improving water quality. Provision for SuDS and the national standards required for their design, construction, maintenance and operation is included in the Flood and Water Management Act 2010.
Surface course – The surface course is the layer of resin and aggregate applied over the base course.
Tarmacadam – Tarmacadam is a trade name (general term) used to describe bitumen macadam although natural tar is rarely used and has been replaced with asphalt or bitumen (bitmac).
Tintagel slate – A StarScape aggregate available in a 1-3mm size.
Tree pit – Tree pits are the areas directly around the base of a tree which is otherwise surrounded by hard landscaping such as paving. The systems are designed to provide an attractive porous resin bound surface which allows tree roots access to both air and water penetration.
Trim – The word ‘Trim’ is used to describe the metal (typically aluminium) strips used to incorporate design features into a resin bound surface.
Trowel – Whilst they can be used, a standard rectangular trowel is not ideal for installing a resin bound surface. A long, rounded edge, steel pool trowel helps prevent the corners from digging into the surface and enables the trowel to glide over the compacted aggregate without leaving trowel burn marks. In our own tests we found that the OX and KRAFT Blue Steel Pool Trowels (18”) are robust and perform exceptionally well.
Trowel burn – Unlike concrete trowel burns which are the result of differing compaction levels, resin bound trowel burn refers to the downwards force scraping resin from the surface of the aggregate and allowing the aggregate to scratch small particles from the trowel which discolour the resin. The use of a stainless (blue/tempered) steel trowel will greatly reduce that possibility of trowel burn or surface blemishing.
Upnor pink – A StarScape aggregate available in a 3-6mm size.
Urea – If the isocyanate component of a resin bound kit is allowed to react with water instead of the resin component this reaction will create a polyurea which is white and brittle.
Urethane – When the two components of a bound surfacing kit are mixed together the resin component reacts with the isocyanate component to form a ‘polyurethane’ which is clear and has very strong, flexible properties.
UV stable – The UV stability refers to the cured surfaces ability to withstand damage from UV radiation (sunlight). StarScape ULTRA is formulated using a 100% UV resistant, aliphatic (UVR) isocyanate and will not discolour or reduce in performance due to damage from UV light. Some manufacturers and distributors have products which are formulated using a non-UV resistant, aromatic isocyanate and these systems will discolour (turn a dirty brown) and become brittle overtime. Other systems available include products that are UV Stable (UVS) in which either an aromatic/aliphatic isocyanate blend is used or a UV stabiliser is incorporated to delay the UV discolouration/damage. This is done in an effort to reduce the formulation cost (not improve quality) and these systems will ultimately still discolour and become brittle over a period of time.
Vela – A StarScape aggregate blend consisting of 75% Upnor Pink 3-6mm and 25% Kendal Gold 1-2mm.
Viscosity – The word ‘Viscosity’ is used to describe a liquids thickness (resistance to deformation). A liquid with a high viscosity (such as honey) is thicker and a liquid with a low viscosity (such as water) flows more freely. The viscosity of a bound surfacing resin can affect the ability of its components to mix together, the amount of resin that covers the aggregate particles, the amount of resin which runs through the aggregate matrix to bond the aggregate to the base and the ease in which the material can be trowelled level.
Volume – The volume (V ) of the aggregate is the space that 1kg occupies and is shown in cm³. This number is important as it directly relates to each aggregates coverage rate which can be far more significant than most users may realise.
Wark gravel – A StarScape aggregate available in a 3-6mm size.
Whitening – Whitening refers to the resin bound surface turning white, typically caused by excess water entering the uncured product which results in a urea reaction (iso and water) rather than a urethane reaction (iso and resin).
White Spirit – A petroleum-derived clear liquid used as a common organic solvent. Unlike the aromatic solvents supplied by Star Uretech which have a specified moisture and hydrocarbon content, generic white spirit varies in quality (and moisture content) and should not be used as a trowel lubricant as this can result in delayed whitening or blooming.
Xylene – An aromatic solvent which can be used to remove spilled, cured resin from brick or other solvent resistant surfaces. Xylene is often used as a trowel lubricant or with a wire brush to remove small stains/spills from the cured surface.
Yellowing – Unlike StarScape ULTRA, some systems are not UV resistant or are only stabilised to UV light. Unlike UV resistant, aliphatic isocyanates, aromatic isocyanates will form an amine which will oxidized to a quinone if subjected to UV radiation. Quinones are yellow and their formation will make the resin surface appear increasingly yellow as the oxidation proceeds over time. Since the quinone structure is part of the backbone of the polymer, the resin surface will appear discoloured before there is any degradation however once the oxidation starts breaking chemical bonds, the degraded polyurethane will lose strength.
Yielden white – A StarScape aggregate available in 1-3mm and 2-5mm sizes.
Zinc oxide – Small amounts of micronized zinc oxide and titanium dioxide can be incorporated into a Non-UV resistant system to temporarily delay the damage and colour change caused by UV light however the surface will eventually degrade.