FOR 50 years resin flooring has been the flooring of choice for many applications due to its excellent performance characteristics which give the client seamless, hygienic, durable and slip-resistant floors.
Synthetic resin flooring systems range from coatings of less than 0.3mm to heavy duty industrial screed systems, which can be several millimetres thick. The many options range from smooth and high gloss systems all the way to surfaces with a pronounced profile and high slip resistance. The magic of chemistry and the skill of the formulator means that a resin floor can be produced that is rigid or flexible, electrically conductive, resistant to aggressive chemicals or has strong aesthetic appeal, depending on requirements.
A correctly specified resin floor, appropriate for the conditions under which it will be used can provide a seamless surface with greatly enhanced performance compared to the concrete base on which it is applied. Resin flooring systems will enhance the ability of the floor area (depending on the FeRFA type selected) to withstand foot and vehicular traffic over long time periods, also helping to prevent slips and trips, it will protect the substrate from the ingress of liquids, while remaining hygienic and easy to clean.
The main advantages of synthetic resin flooring can be summarised as follows:
- strong permanent bond to the concrete base, when prepared correctly
- resistance to a wide range of chemicals
- impermeable to liquids
- tough and durable, which increases the floor’s resistance to impact and abrasion
- hygienic and good cleanability
- rapid installation and curing with minimum disruption to normal operations
A variety of different types of synthetic resins are available to form the binder of a flooring system. These include epoxy, polyurethane, methacrylate and polyaspartic resins. Different resin types give different combinations of application characteristics and in-service performance and the considerations which affect the selection of a particular type should be discussed with the specifier.
Classification of synthetic resin flooring types
FeRFA, the Resin Flooring Association, represents the majority of companies in this sector and has developed a classification system for the different resin flooring types. This is the basis of the British Standard Code of Practice BS 8204-6. The resin types are defined from 1 to 8 based on the applied thickness and surface finish. The FeRFA classification system allows a cross-reference between products from different manufacturers, irrespective of brand names, and provides useful guidance when selecting a resin flooring system.
In general terms, flooring types are listed in ascending order of durability. However, the actual lifespan in a particular installation will depend on the product formulation used, the quality of the substrate and the degree of severity of the service conditions. Care must be taken to ensure that manufacturers’ data sheets and recommendations are fully considered before selecting products for a specific set of circumstances or conditions. Some of these types of flooring may be produced with special decorative effects by the incorporation of coloured particles or flakes in the surface.
Terrazzo-like finishes (ground exposed aggregate) may be produced from certain trowel-applied floorings and slip resistant or anti-static/conductive versions of all of these categories may be available.
The FeRFA Guidance Note ‘Guide to the Selection of Synthetic Resin Floors’ contains further information.
Training and quality assurance are important to ensure that new resin floors are correctly installed. FeRFA endorses and actively promotes “Qualifying the workforce” through the provision of NVQ Level 2 training schemes in resin flooring, screeding and surface preparation. Meanwhile FeRFA continues to take a leading role in developing national and international standards for resin flooring and screeds.
Synthetic resin flooring is extremely tough and durable and can have a life expectancy in excess of 20 years when specified and installed correctly. In such cases, the majority of the life cycle cost will be in regular cleaning and maintenance as is required for all flooring types. However, resin flooring is easier to clean than most types of flooring and a wide range of high-performance, specially formulated cleaning products is available to help with the job. The choice of good cleaning chemicals is key to success and skimping on this element can be false economy. Studies have shown that chemicals can represent only 6% of the total costs of an effective cleaning regime with labour and equipment forming the bulk of the cost. In addition, resin flooring can generally be refurbished by overcoating with a lower thickness than applied originally.
The most appropriate flooring for any situation will depend upon the conditions to which it will be subjected, and the choice should be made in discussions between all interested parties including client, designer, contractor and manufacturer. It is not possible to provide a simple guide to where to use different flooring types since so many parameters can affect the decision. Factors influencing the selection of a flooring system include:
- type and degree of traffic
- temperatures to which flooring will be exposed
- nature and duration of any chemical contact with the floor
- wet or dry service conditions
- slip resistance requirements aesthetics
- ease of cleaning and special hygiene requirements
- type and moisture content of the substrate
- time available for the application and cure of the flooring
- prevailing site conditions at the time of installation
The FeRFA Guidance Note ‘FeRFA Guide to the Specification & Application of Synthetic Resin Flooring’ contains further information on these topics.
In very general terms, the service life will be proportional to the applied thickness of the flooring. However, many operational factors will directly affect the performance including the severity and type of trafficking, the frequency and efficiency of cleaning, mechanical handling abuse and degree of impact damage. In most industrial facilities there will be a variety of areas in which different types of resin flooring will be the most appropriate. Conversely there will be areas where some types are completely inappropriate.
Surface smoothness and slip resistance
As a general rule, the smoother and less porous a floor surface is, the easier it is to keep clean.
However, whilst resin flooring can be formulated to produce smooth, non-porous surfaces with excellent slip resistance under dry conditions, the surface may have to be textured if it is to have adequate slip resistance under contaminated conditions. The heavier the likely build-up of contaminants, the coarser the surface texture must be to retain the required level of slip resistance.
However coarse textured surfaces are more difficult to clean, so where both slip resistance and ease of cleaning are important, a compromise must be made. Flooring should be selected with sufficient texture to suit specific working conditions and hygiene standards, and a programme of frequent effective cleaning must be set in place. Apart from the selection of the flooring, the use in particularly wet areas of special footwear with slip resistant soles can be beneficial in allowing a smoother floor finish to be adopted.
Slip resistance is covered in the FeRFA Guidance Note ‘Measuring and Managing
the Level of Slip Resistance Provided by Resin Floors’.
Well formulated and correctly applied resin flooring systems are an effective method of protecting concrete substrates, sensitive to attack, from aggressive chemical spills. Whilst no floor finish is completely resistant to prolonged contact with high concentrations of all possible chemical types and combinations, selected synthetic resin floorings are resistant to many of the chemicals and products found in normal industrial service situations.
By provision of adequate drainage and maintenance of good housekeeping standards, excellent service life can be achieved under conditions of highly aggressive chemical spillages. Because of the wide variety of chemical products used in industry and the diversity of synthetic resin floorings it is not practicable to provide a simple guide to chemical resistance. Advice should be sought from the manufacturer or contractor based on their experience in similar locations or on laboratory testing.
Resistance to particular chemicals does not exclude the possibility of surface staining. Some chemicals may cause discoloration of the flooring surface without affecting the service integrity and durability of the flooring material. If aesthetic appearance is a major requirement, it is essential that the user should establish whether the proposed flooring will be resistant to staining as well as chemical attack in the particular environment.
Further information is obtained in the FeRFA Guidance Note ‘Chemical Resistance of Resin Flooring’.
Synthetic resin flooring is generally selected for use because of specific performance requirements that other flooring types cannot achieve. Therefore, the importance of visual aesthetics (e.g, colour, UV stability, surface texture and consistency) can be overlooked, which may then result in post installation contractual complications and/or disappointment for the customer. If aesthetic appearance is a major requirement then the flooring system should be chosen accordingly.
Control of static electricity
Static controlled grades of resin flooring are available complying with various national and international standards. It is important for the specifier to understand that there is a wide range of products and properties available and to select the system that best meets the requirements for the working environment as a whole and to not treat the individual elements in isolation. Colour should be discussed with the flooring manufacture as there may be certain colour limitations on anti-static flooring due to the darkening effect of carbon.
This subject is covered by the FeRFA Guidance note ‘Static Controlled Flooring’.
Most synthetic resin types have relatively low Heat Distortion Temperatures (HDT), generally between 50 and 100deg C and much lower than ceramic tiles or concrete floors. In practice, certain synthetic resin flooring types have proved capable of withstanding considerably higher temperatures than their HDT through attention to formulation, application and floor design. Dry heat is normally only a problem in extreme conditions, e.g, close to oven doors. Liquids in contact with floors give a much higher heat transfer and therefore pose more of a risk. Wherever possible, discharges should be piped directly to the drains. Particular care should be taken in the design of the flooring where extreme temperature variations are likely, such as in cold stores and areas around ovens or furnaces. Prolonged exposure to high temperatures may lead to a degree of post cure resulting in the product becoming more brittle or less flexible, and in the worst cases inducing shrinkage stresses within the product leading to cracking or detachment. On the more heavily filled resin floorings of Type 8, when applied at a thickness of 9mm or more, steam cleaning can be satisfactorily carried out provided care is taken to ensure that the steam lance is not allowed to discharge on one place for too long. However, for thin layer flow applied flooring, modern cleaning and sterilising agents and machines are generally more cost effective than steam cleaning.
Taint and other contaminants
Specially formulated and fully cured synthetic resin flooring meets the hygiene requirements for areas where foodstuffs are prepared, treated and processed in terms of being easy to clean, impervious, non-absorbent and non-tainting. Manufacturers have several test methods at their disposal to demonstrate compliance with these requirements. The critical periods when tainting and/or contamination is likely to occur are during the surface preparation, application of the flooring system and the subsequent curing. During these periods, all foodstuffs should be removed or isolated from the work area and particular care taken to ensure extracted air from the work area is directed away from areas where foodstuffs are stored.
A minimum slope of 1 in 80 should be specified to produce a free draining floor. However, a textured surface may require a higher slope in order to allow free draining. Slopes greater than 1 in 60 may lead to problems of slumping if the final finish is to be flow-applied.
Surface preparation is a most vital aspect of synthetic resin flooring application. Inadequate preparation will lead to loss of adhesion and failure. All surface contamination such as oil, paint and adhesives on old concrete bases and the laitance and any surface sealer or curing membrane on new concrete bases should be entirely removed by suitable mechanised equipment, e.g. shot blasting, planing or grinding, to expose the coarse aggregate. For the thinner synthetic resin floorings of Types 1-5, grinding or light contained shot-blasting is preferred, so that the profile does not reflect in the finish. After surface preparation, all loose debris and dirt should be removed by vacuum equipment. Comparable procedures are available for other substrates such as timber and metal, but the flooring manufacturer’s instructions for surface preparation and priming should be strictly followed.
Refer to FeRFA Guidance Note ‘FeRFA Guide to Preparing Substrates to Receive Resin Flooring and Finishing of Terrazzo Systems’.
It is important that good housekeeping standards are established and maintained appropriate for the type of resin flooring installed. In order to ensure the flooring is kept in a hygienic condition, without long term damage being caused, close liaison is needed between the client, contractor and the flooring manufacturer to identify the most appropriate procedure for regular and thorough cleaning. Generally, a mechanical scrubber with wet vacuum is the most suitable. Washing with mop and bucket is not recommended. Where hygiene levels are required to be high, e.g. in food preparation areas, a special cleaning schedule should be developed.
Please refer to FeRFA Guidance Note ‘FeRFA Guide to Cleaning Resin Floors’.
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