Altro Flow 1mm, 2mm, 3mm standard

Altro Flow 1mm standard,
Altro Flow 2mm standard and
Altro Flow 3mm standard

Self-smoothing epoxy flooring
Technical and installation data sheet

January 2019

Product description
FeRFA type 5

Altro Flow 1mm standard, Altro Flow 2mm standard and Altro Flow 3mm standard are three-part solvent-free epoxy resin based self-smoothing floor topping, which produce a smooth, attractive and easily cleaned seamless floor. Altro Flow has a high gloss finish but can be sealed with Altro Seal water based matt for an aesthetically pleasing matt finish.

Standard colours

The Altro Flow variants are available in a range of 25 standard colours. Bespoke colours are available within constraints. In common with other epoxy products lighter colours will be prone to cosmetic yellowing on exposure to UV light. Single colour high gloss finishes may exhibit scratching and abrasion, this is particularly prominent in dark colours. A metallised maintenance coating, such as Altro Gloss 211 can offer ongoing protection, subject to customer requirements and environment.

Typical areas of use

  • Production halls (dry operations)
  • Clean rooms
  • Commercial corridors and offices
  • Laboratories
  • Dry storage areas
  • Packing areas


  • Ease of installation
  • Ease of cleaning
  • Good chemical and stain resistance
  • Fully bonded to the substrate
  • Excellent decontamination
  • Provides a seamless floor finish (substrate joints must be cut through)


Altro’s steps to sustainability program seeks to optimise our performance with respect to the planet’s resources. Please refer to for further information.

Chemical resistance

Altro Flow variants offer good resistance to a range of commonly used chemicals. However, premature contact with chemicals (including water) during the curing process may give rise to discolouration, staining and variation in gloss. In all cases of chemical spillage, it is essential that the spillage be immediately removed and the surface washed down with clean water, removing water by wet vacuum after operation. Although some chemicals may cause discolouration, this may not affect the durability and integrity of the resin screed. Please refer to Altro and FeRFA Guidance Note No.3 for further information.

Typical physical properties

Slip resistance We do not recommend Altro Flow where there is risk of a slip
Usable working life 30 minutes @ 20°C
Speed of cure Light foot traffic - 48 hours at 20°C
Full cure – 7 days at 20°C
Bond strength EN 4624 B3,5
Impact strength ISO 6272 (2mm and 3mm variants IR2
Reaction to fire EN 13501 CFL-s1


Altro Flow 1mm standard is available in a 16.6kg, three-part composite pack.

Altro Flow 2mm standard and Altro Flow 3mm standard are available in a 24kg, three-part composite pack.


Altro Proof standard
18m2 per 6kg unit

Altro Flow 1mm standard
10.7m2 per 16.6kg unit.

Altro Flow 2mm standard
6.7m2 per 24kg unit

Altro Flow 3mm standard
4.5m2 per 24kg unit

Altro Seal water-based matt (optional clear cosmetic matt finish)
Single coat 100m2 per 5kg unit

Material usage is dependent upon temperature, surface profile and porosity; stated coverage rates should be referred to for guidance only and cannot be relied upon to determine exact quantities.

Although stringent quality assurance processes are employed, when colour consistency is required a single batch should be used.


Ensure that the product is received in good order and store in a dry, frost-free environment, ideally between 15°C and 20°C for at least three days before laying.

It is important to maintain the aggregate temperature during storage. Low temperature in the aggregate will adversely affect the product application.

Excessively high and low storage temperatures will affect the laying performance of the product.

Suitable substrates

Altro Crete may be applied to a variety of substrates including, but not limited to, concrete, polymer-modified cementitious screeds, terrazzo, 25mm marine-grade plywood (consult Altro for further guidance). For all proprietary subfloor systems refer to the manufacturer for recommendations and seek further guidance from Altro.

FeRFA, The Resin Federation, does not recommend Calcium Sulphate, Anhydrite or Hemi-hydrite screeds for overlayment with synthetic resin surfaces.

Substrate requirements

Altro Flow may be applied to a variety of substrates including, but not limited to, concrete, polymer-modified cementitious screeds, terrazzo and 25mm marine grade plywood (consult Altro for further guidance). For all proprietary subfloor systems refer to the manufacturer for recommendations and seek further guidance from Altro. FeRFA, The Resin Federation, does not recommend Calcium Sulphate, Anhydrite or Hemi-hydrite screeds for overlayment.

Substrate preparation

Substrates should be dry, structurally sound and free from contamination, friable materials or laitance which may affect either the adhesion or penetration of the resin system. All residues of old paint coatings and dust must be removed. Substrates to achieve 26N/mm² compressive strength (BS EN 12504-2:2001) and surface tensile strength 1.5N/mm² (BS EN 13892-8). Substrates must include an effective damp-proof membrane and contain residual moisture not greater than 5% by weight (75% R.H.) to BS 8203.

On substrates liable to direct hydrostatic pressure such as some basements, low lying buildings, in the absence of an integral DPM, a more substantial installation may be required. Concrete floors must be constructed in accordance with the British Standards BS8204 Part 1, Code of Practice.

Thin-bed synthetic resin systems follow the surface of the substrate, so it is essential that the surface regularity of flatness conforms to or exceeds BS 8204.2 class SR2 (+/- 5mm under a 2 metre straight edge). Any deviation from this may require a surface improver to be applied which must be suitable to receive an epoxy resin overlay.

Please consult Altro or FeRFA’s Guide to the Specification and Application of Synthetic Resin Flooring for further guidance.


Surface preparation is the most vital aspect of resin flooring application. Inadequate preparation will lead to loss of adhesion and failure. The substrate in question will dictate the method of preparation. In the case of a concrete floor, preparation by dust enclosed diamond floor grinder may be appropriate, or if of a sufficient area for economic reasons, should be lightly shot blasted to leave a textured surface free from contamination.

If the floor has been treated with a cementitious surface improver, then the surface should be prepared in accordance with the manufacturer’s recommendations, or abraded with an STR machine followed by thorough vacuuming.

Treatment of local repairs such as cracks and holes, improvement or modification of levels and removal of high spots, should be undertaken prior to the flooring installation. Application onto cold substrates can give rise to pinholes in the finished system if the ambient temperature rises during application causing micro pockets of air in the concrete substrate to expand and be displaced through the resin. Ambient and substrate temperatures should be raised prior to installation, and kept constant during application.

Please consult Altro or FeRFA’s Guide to the Specification and Application of Synthetic Resin Flooring for further guidance.


The following application guide is based on laboratory and simulated site conditions. However, when installation conditions differ appreciably from those detailed by Altro, the performance characteristics of both mixing and laying may not be as expected. To achieve the best results at all times please endeavour to establish the correct conditions which in turn will allow the materials to be laid effectively and meet your customer’s expectations.

Installation conditions

Apply in well ventilated areas. Both the slab and air temperature should be between 10°C and 25°C. It is not advisable to mix and lay epoxy resin products outside of that range. Ambient conditions should be maintained at least 3°C above dew point or below 75% RH during the initial stages of cure. At site temperatures below 10°C cure times will be substantially increased unless some form of external heating is used. Avoid using heating sources that give rise to high levels of humidity, such as those burning fossil fuels. It must be recognised that the concrete slab temperature will generally be lower than the air temperature, often as much as 10°C, and this will govern the rate of cure. As the resin flooring cures, in condensing conditions moisture vapour may condense onto the surface and cause ‘blooming’, a permanent clouding of the surface.

Do not lay the Altro Flow product on a raising thermometer as this can give rise to pinholes. Raise the substrate temperature prior to application and maintain the temperature of the substrate during application.

The workability, open-time, cure development and return to traffic will be significantly affected by ambient conditions.

Mixing equipment

* All tool number references relate to Refina Ltd 01202 632 270

  • Slow speed drill (200-500rpm), such as MM17 *
  • Mixing paddle, such as MR3
  • Mega Mixer MM22 with MR3 Paddle
  • Stainless mixing vessel, such as RM65 drum *

Priming the substrate

In order to achieve a uniform finish, prevent bubbles and maximise substrate adhesion a primer should be used. An Altro primer should be selected which is suited to the installation, and appropriate for the nature and moisture content of the substrate (seek further guidance from Altro). For Altro Flow variants Altro Proof standard is recommended.

For substrates with greater than 75% RH BS 8203 an effective damp-proof membrane should be laid such as Altro Proof. Do NOT seed the primer with aggregate, experience shows that this can lead to pinholes from entrapped air. Ensure that the substrate is well sealed and that all hungry areas are addressed before proceeding to install the system. If the over-coating time period for the primer is exceeded, the surface should be lightly abraded and vacuumed before further coats are applied.

Product installation

Using a slow speed drill and whisk, thoroughly mix the base colour for 30 seconds until uniform. Pour all the hardener contents into the base bucket and mix thoroughly for a further 90 seconds. The aggregate should be added gradually into the pre-mixed binder, whilst continuing the mixing action, and mix for a further 2-3 minutes. Excessively vigorous mixing should be avoided as this can lead to undesirable air entrainment. Care should be taken to ensure that any material adhering to the sides, bottom and corners of the mixer is thoroughly blended in. If the mixing area is not adjacent to the laying area the time required to transfer the mixed material will reduce the open installation time. Remember to always use the correct PPE.

Decant all of the contents of the mixing vessel onto the floor and spread to the desired depth using a clean stainless steel trowel or a pin rake set at the desired depth. Spike roller the area immediately, NOT beyond 20 minutes @ 20°C. Do not exceed this time between gauges. Care should be taken to ensure the mixing vessel is kept free of any build-up of contaminants which could fall off and contaminate the floor.


In common with other single colour high gloss finishes, Altro Flow may exhibit scratching with traffic and abrasion, this is particularly prominent in darker colours. Any undulations and imperfections will stand out in specific lighting conditions. This effect can be minimised by finishing the floor with a matt seal which will diffuse the light and hide undulations.

To achieve a cosmetic matt finish, the application of a single coat of Altro Seal water-based matt can be applied not more than 24 hours at 20°C following the application of the Altro Flow. Additives at the surface of the Altro Flow will require removal prior to the application of the Altro Seal water-based matt seal coat. This is to ensure effective intercoat adhesion. Clean the surface of the Altro Flow with Altro Solve™ EP or Altro Siliclean without allowing ponding. Do not re-use paper towels as this will have the effect of spreading any contaminants across the surface of the floor causing orange peeling in any subsequent coating.

Pour the contents of the hardener into the base unit and thoroughly mix using a slow speed drill and paddle for two minutes. Apply a very thin coat using a short nap synthetic roller applying the product to the floor from a paint tray. Heavy application of this seal will result in an opaque appearance of the finished floor; therefore, care is required in its application.

It is important to note that enough time should be given to allow the Altro Seal water-based matt to reach its full chemical cure. Physical drying of the surface alone is not indicative of the full cure properties including wear and chemical resistance.


The spacing of movement joints must be determined by the design of the subfloor. All live movement joints in the subfloor must be continued through the resin flooring. In all instances the type and positioning of movement joints should be agreed at the design stage between all parties concerned. Please refer to Altro or FeRFA’s Guide to the Specification and Application of Synthetic Resin Systems for further guidance. All joints should be filled with Altro Expand flexible jointing compound. Please see Altro Expand data sheet for further information.


Whilst of an extremely durable nature these floor systems must by thoroughly protected from the rigours and abuse that exist during the ongoing contractual works. The resin floor should reach full chemical cure in 7 days at 20°C. Untreated felt paper will suffice as protection from light traffic, however if protection is required from other trades then the following protection option should be considered. Where heavier access is required then a more suitable medium to take the loadings, such as shuttering ply or Correx by Cordek, should be placed on top of the untreated felt paper. The resin system should have cured for 48 hours prior to placing the protection. No polyethylene sheets, linseed-treated hardboard, print or dyed card should be placed in contact with the resin surface. All joints in the protection medium should be taped, and all accidental spillages should be recovered immediately by removal and reinstatement of the protection. Damage will occur to the guidance is not followed.

Cleaning (during installation)

All tools and equipment should be regularly cleaned using Altro Solve EP to reduce build-up and maintain the quality of the installation. Ensure that the correct PPE is worn at all times.


Due diligence must be adopted if accidental spillages occur. Recover using absorbent granules, transferring into a suitably marked container. Disposal of all empty containers and accidental spillages should be in accordance with the local waste disposal authority.

Cleaning guidance

Optimum slip resistance and appearance can only be maintained with regular cleaning. Floors with slip resistance will require mechanical cleaning; wet loop mop cleaning will be less effective but may be sufficient for routine maintenance of floors with a smooth surface. Microfibre cleaning systems should be sufficient for routine maintenance of floors with a smooth surface provided that a suitable detergent / dosage is used and the microfibre pads are changed with sufficient frequency to ensure their effectiveness. Steam cleaners and / or hot pressure cleaners should not be used on the floor.

A cold / ambient pressure washer may be used if required, but the pressure should not exceed 1400psi. Warm water will offer improved cleaning, but the water temperature should not exceed 60°C.

Entrance matting will reduce cleaning requirements and should also enhance the longevity of the floor, when combined with correct maintenance.

  • Sweep or vacuum the floor to remove debris
  • For normal cleaning, dilute an alkaline detergent, such as Altro Clean 44 or similar, by 1:40 in clean water
  • Alternatively, dilute by 1:20 for infrequent heavy cleaning
  • Liberally apply the water and detergent solution to the floor, scrubbing with a deck scrubber or slow-speed (< 400rpm) scrubbing machine and Altro UniPad or similar
  • Pay particular attention to areas where residues may accumulate, such as internal corners of perimeter coves and around columns etc
  • If possible, allow the detergent solution to remain on the floor for several minutes to break down deposits, but not sufficiently long to allow the solution to evaporate
  • Remove the solution by wet vacuum recovery and follow this with a fresh water rinse, or rinse the solution into drains if permissible
  • It is important that all detergent residue is removed from the textured surface of the floor. Detergent may become slippery which affects safety, or sticky which attracts and holds more dirt

Please obtain the correct material safety data sheets from Altro prior to beginning your installation.

Always wear correct PPE whilst installing resin products.

For further information or technical advice
call our Customer Care Centre on 01426 489516
or email:

NOTE: “Altro Ltd” (“Altro”) endeavours to ensure that advice and information given in Product Data Sheets, Method Statements and Material Safety Data Sheets (all known as Product Literature) is accurate and correct. However, where Altro has no control over the selection of its products for particular applications, it is important that any prospective customer, user or specifier, satisfies him / herself that the product is suitable for the intended application. In this process, due regard should be taken of the nature and composition of the background / base and the ambient conditions both at the time of laying / applying / installing / curing of the material and when the completed work is to be brought into use.

However, as site conditions and the execution of the work are beyond our control, we accept no resultant liability.

Altro’s policy is one of continuous research and development and we reserve the right to update our products and information at any time without prior notice.