Description
Grey Atlas Silicone Render 25 kg — Self-Cleaning Facade Finish (1.5 mm / 2.0 mm)
Product Overview
Grey Atlas Silicone Render is a ready-mixed, fibre-reinforced silicone finish coat in a 25 kg bucket that delivers up to 11.4 m² of coverage at 1.5 mm grain — the same high-yield formula as the white variant, built on a grey pigment base that reaches full colour depth faster on mid-tone and dark SAH shades. Part of the premium silicone render collection, this grey-base variant is formulated with silicone and siloxane resins, dolomite aggregates, and cellulose-fibre reinforcement, producing a hydrophobic, flexible coating classified A2-s1, d0 for reaction to fire under EN 15824:2017 (DoP 145/3/CPR, verified against the current 2017 edition). ETA references ETA-06/0081, ETA-06/0173, and ETA-16/0933 complete the certification chain for Building Control sign-off.
Available in two aggregate sizes — 1.5 mm (N-15) for a fine lambskin texture with peak coverage, and 2.0 mm (N-20) for a heavier texture that forgives minor basecoat imperfections — every tub is tinted to your chosen shade at our Southampton warehouse on a dedicated Atlas mixing machine. The full 480-shade SAH palette is available as standard, and bespoke colours matched to RAL, NCS, or other manufacturers' references are mixed to order for projects that need something outside the standard range. The grey base is the recommended starting point for any shade from warm sandstone through to deep charcoal, because the grey pigment builds richer colour saturation with less material than a white base.
Your chosen shade stays true for the life of the facade thanks to UV-stable hybrid pigments validated through Xenotest accelerated weathering trials, while the high silicone-resin content lowers surface tension enough for each rainfall to actively lift embedded dust and urban pollutants — so the facade cleans itself year after year.
Key Benefits
- Deeper, Richer Colour in Fewer Coats: The grey pigment base reaches full colour depth on mid-tone and dark SAH shades faster than a white base, meaning a single application delivers the uniform, saturated finish your facade needs — reducing both material consumption and on-site time compared with tinting over white.
- Self-Cleaning Facade That Stays Clean for Decades: The high silicone and siloxane resin content lowers surface tension so every rainfall event actively washes dirt, dust, and airborne pollutants from the finish — your grey or tinted facade maintains its clean appearance without manual washing or repainting.
- Crack-Free Flexibility Through Seasonal Movement: Cellulose-fibre reinforcement combined with dedicated polymer resins allows the coating to flex with thermal expansion and contraction rather than cracking. The elastomeric matrix absorbs building movement and minor site impacts up to 140 J in certified system assemblies, keeping the surface intact through UK temperature swings.
- Year-Round Application Down to 0 °C: A standard working range of +5 °C to +30 °C extends to 0 °C with the addition of Atlas Eskimo setting accelerator, so your project schedule runs through the colder months without compromising cure quality or finish durability.
- Walls That Breathe Freely: A vapour permeability rating of V2 — high (Sd 0.14–1.4 m) allows trapped moisture to escape outward through the render rather than building up inside the wall layers, protecting the building fabric from interstitial condensation and helping maintain a healthy indoor environment.
- Up to 11.4 m² Coverage per 25 kg Bucket: At 1.5 mm grain applied by hand, consumption starts from just 2.2 kg/m², meaning each tub covers a generous area and reduces the number of buckets you need on site. Machine application lowers consumption further to 1.9 kg/m² (approximately 13.2 m² per bucket), cutting material handling time on larger projects.
Technical Specifications
| Property | Value |
|---|---|
| Pack Size | 25 kg plastic bucket |
| Colour | Grey (Platinum) base — tintable to 480 SAH shades (mixed to order in-house); bespoke colours available |
| Grain Size Options | 1.5 mm (N-15) / 2.0 mm (N-20) |
| Density | ≈ 1.9 g/cm³ |
| Consumption — 1.5 mm Hand | From 2.2 kg/m² (≈ 11.4 m² per bucket) |
| Consumption — 1.5 mm Machine | From 1.9 kg/m² (≈ 13.2 m² per bucket) |
| Consumption — 2.0 mm Hand | From 2.8 kg/m² (≈ 8.9 m² per bucket) |
| Adhesion to Substrate | ≥ 0.35 MPa |
| Water Vapour Permeability | V2 — high (Sd 0.14–1.4 m) |
| Water Absorption | In2 — average |
| Reaction to Fire | A2-s1, d0 (EN 13501-1) |
| pH | 8 |
| Application Temperature | +5 °C to +30 °C (0 °C with Atlas Eskimo) |
| Relative Humidity at Application | < 80 % |
| Surface Dry Time | ≈ 15 minutes (at 20 °C, 60 % RH) |
| Full Cure Time | ≈ 24 hours (at 20 °C, 60 % RH) |
| Shelf Life | 12 months from date of manufacture |
| Standard Compliance | EN 15824:2017 (current edition) |
| DoP Number | 145/3/CPR |
| ETA References | ETA-06/0081, ETA-06/0173, ETA-16/0933 |
Application and Compatibility
Grey Atlas Silicone Render works as the finishing coat within a complete external wall insulation or prepared mineral-render system, giving you a durable self-cleaning surface over a properly cured reinforced basecoat. The product is compatible with graphite EPS, XPS, and mineral wool insulation within certified ETICS assemblies, and it performs equally well over sound concrete and traditional cement or cement-lime plasters on renovation work — one product that covers both new-build and retrofit projects.
- Mandatory Primer Coat: A quartz primer controls suction and ensures a uniform colour finish — use Atlas Cerplast or Ceresit CT 16 from the exterior render primer range to prepare the basecoat surface before the render goes on.
- Reinforced Basecoat Layer: Embed alkali-resistant Atlas 150 g/m² fibreglass mesh into a fibre-enhanced adhesive mortar (Atlas Hoter U Grey or Hoter U White) to create the crack-resistant reinforcement plane beneath the finish.
- Grain Size Selection: Choose 1.5 mm (N-15) for the finest lambskin texture and peak coverage on a well-prepared, even basecoat; choose 2.0 mm (N-20) for a heavier texture that is more forgiving visually on larger or less uniform elevations.
- Colour — Mixed to Your Specification: Every tub is tinted at our Southampton warehouse on a dedicated Atlas mixing machine. The full 480-shade SAH palette is available as standard, and bespoke colours — including shades matched to RAL, NCS, or another manufacturer's reference — are mixed to order. The grey base is the recommended starting point for mid-tone and dark tints; for the lightest shades and pure white, the white-base variant delivers a brighter result. Browse the colour charts and sample catalogues to confirm your shade on a physical chip before ordering.
- Plinth and Impact Zones: For ground-level areas exposed to splashback or minor impacts, pair this grey finish with a textured plinth treatment from the mosaic render collection to add durable protection below the DPC line.
Installation Notes
Faster, more consistent results start with correct preparation: allow the primed basecoat to cure for a minimum of three days at +20 °C before applying the render, ensuring the substrate is stable, dry, and free of dust. Stir the ready-mixed mass thoroughly with a low-speed paddle mixer — the product must not be combined with other materials, diluted, or thickened. Apply with a stainless-steel trowel at aggregate thickness, then texture immediately using a plastic float in a circular motion to achieve the lambskin effect.
- Wet-on-Wet Technique: Work across a full elevation without allowing one section to skin over before the next is applied — this eliminates visible lap marks and ensures a uniform tone across the entire facade plane, which is especially important with darker SAH tints where even minor differences become visible in raking light.
- Optimal Conditions: Choose a dry day between +5 °C and +30 °C with relative humidity below 80 %; these conditions let the silicone resins cross-link properly, locking in the self-cleaning surface and full colour depth within 24 hours.
- Batch Consistency: Apply render of the same manufacture date across one continuous surface to prevent batch-related shade variation, and plan technological breaks at building corners, colour junctions, or downpipe lines.
For temperatures between 0 °C and +5 °C, adding Atlas Eskimo setting accelerator (0.25 kg per bucket) protects the fresh render during the longer cold-weather drying window — the full seasonal protocol is covered in the cold-weather rendering guide.
Trade Insight: Installer's Note
Grey base is the go-to choice whenever I am tinting to anything from a warm sand to a charcoal — starting on a grey pigment means the colour builds up faster and with more consistent depth than working from white, and that translates directly into fewer coats and less material on site. I always run a straight edge across the cured basecoat before priming to catch any high spots, because the 1.5 mm aggregate telegraphs every imperfection — and on a dark shade in raking light, even a shallow ripple stands out. For machine application, the 1.5 mm version runs cleanly through a Wagner PC 830 or Graco RTX 5500 PX with a 6 mm round nozzle at moderate feed settings; flushing the hose with a small quantity of Cerplast or Silkon ANX before pumping the render ensures a smooth, uninterrupted feed from the first pull of the trigger. The full method from basecoat preparation through to final texturing is detailed in the thin-coat render application step-by-step guide.
Is This Product Right for Your Project?
- Choose This Render If: You want a contemporary grey facade or a rich mid-to-dark tinted finish for a residential or commercial project — the grey pigment base reaches full colour depth faster than a white base, the self-cleaning silicone surface keeps the finish looking sharp without repainting, and the 1.5 mm grain delivers up to 11.4 m² per bucket. Every tub is tinted to your chosen SAH shade at our warehouse, and bespoke colour matching is available for non-standard references.
- Need Lighter Shades or Pure White? The white-base 25 kg Atlas Silicone Render in the same range uses an identical silicone-siloxane formula with a white pigment base — it is the better starting point for the lightest shades and pure white facades, where its high solar reflectance also reduces thermal stress on the coating for extended service life.
- Consider an Alternative If: You are rendering an older heritage or lime-based wall that needs a more mineral, conservation-friendly specification — in that case, the silicone-silicate render is usually the better fit for historic substrates that require maximum vapour permeability and mineral compatibility.
Frequently Asked Questions
How much grey Atlas Silicone Render do I need per 100 m²?
At 1.5 mm grain applied by hand, consumption starts from 2.2 kg/m², so 100 m² requires a minimum of 220 kg — that is 9 buckets (25 kg each). Adding 5–10 % for site waste, corner detailing, and uneven substrates brings a practical order to 10–11 buckets. At 2.0 mm grain the consumption rises to 2.8 kg/m², requiring at least 12 buckets for the same area. The render coverage calculator confirms the exact quantity for your project dimensions.
Is this the same formula as the white variant?
The grey and white variants share an identical silicone-siloxane resin matrix, cellulose-fibre reinforcement, and performance ratings — only the base pigment differs. Both are classified A2-s1, d0 for fire reaction and carry the same DoP (145/3/CPR) under EN 15824:2017. The grey variant delivers deeper, richer colour saturation for mid-tone and dark tinted finishes, while the white variant is optimised for the lightest shades and pure white facades where high solar reflectance reduces thermal stress on the coating.
Will the grey finish yellow or discolour over time?
The grey pigment is integrated throughout the full depth of the render using a hybrid inorganic-organic pigment system validated by Xenotest accelerated weathering trials for long-term UV resistance — so the finish resists fading far better than a surface-applied masonry paint. The self-cleaning silicone surface also prevents airborne dirt from embedding into the texture, keeping your chosen shade visibly consistent between natural rain washes for the full service life of the facade.
Is grey Atlas Silicone Render environmentally responsible?
The render is a water-based formulation containing no solvents, and its environmental performance has been independently verified through a Type III Environmental Product Declaration (EPD) — a third-party lifecycle assessment that architects and developers can reference in BREEAM or sustainability submissions. The long service life and self-cleaning properties also reduce the need for maintenance chemicals and repainting over the building's lifetime, lowering the overall environmental footprint of your facade system.
Technical Documentation