Description
For premium, high-exposure facades that need certified ETICS performance and lifetime self-cleaning, Atlas Gemini RS Grey 25 kg delivers 10.9 m² hand coverage at 1.5 mm grain (≥ 2.3 kg/m²) under BBA Agrément 13/5018, with 3D-Flex elasticity, Mirror Effect UV reflectance, and Biosec capsule biocide built into every tub.
Where Atlas Gemini RS Grey Performs Best on UK Facades
At ≥ 2.3 kg/m² hand coverage with a 4K mineral-aggregate matrix and siloxane-enhanced resins, Atlas Gemini RS Grey is built for the elevations that take the heaviest punishment — heavy urban pollution, mechanical impact, shaded greenery, and full UK weather exposure — certified within the Atlas ETICS system under BBA Agrément 13/5018 (EN 15824:2017, V2 permeability, W2 absorption, adhesion ≥ 0.35 MPa, DoP 280/CPR). It sits in the premium silicone render range as the impact- and pollution-resistant grade for demanding commercial and high-traffic facades.
The grey pigment base is the natural starting point whenever the specification calls for mid-tone or dark SAH shades, since deep charcoals, rich blues, terracottas, and saturated architectural greys all reach full colour depth from the first coat without the multiple-pass burying a white base would need. Three integrated technologies sit beneath the finish: 3D-Flex elasticity bridges thermal stress, Mirror Effect high-reflectance additives lower surface temperature to slow UV pigment fade, and Biosec capsule biocide releases active agents gradually across the coat's service life.
Why Trade Specifiers Choose Atlas Gemini RS Grey
- BBA-certified within Atlas ETICS: BBA Agrément 13/5018 covers the complete assembly — adhesive, reinforcing layer, primer, and finish coat assessed together — giving Building Control and warranty providers a single compliance pathway, subject to the project's own fire strategy.
- 3D-Flex crack-bridging elasticity: high-concentration polymer resins and cellulose fibres absorb thermal expansion, freeze-thaw cycles, and minor impacts without micro-cracking, so the facade stays intact through every UK winter.
- Mirror Effect UV reflectance: high-reflectance additives lower the surface temperature of the finished coat, slowing pigment fade and extending colour life on dark and saturated shades that would otherwise be vulnerable to UV stress.
- Biosec biological defence: encapsulated biocide releases active agents gradually over the coat's service life, suppressing algae, mould, and lichen on shaded elevations near greenery or water without repeat treatments.
- Self-cleaning siloxane surface: a dense, hydrophobic siloxane layer lets rainwater rinse airborne dirt and pollutants away naturally, dropping maintenance to occasional soft-washing rather than scheduled cleaning.
- Grey-base pigment depth for dark SAH shades: the grey starting point reaches deeper saturation in the first coat than a white base, cutting material use and on-site time on contemporary facades specifying mid-tone to dark tints.
- Tinted on site with next-day dispatch: every tub is mixed to your chosen SAH shade at the Renders World Southampton warehouse on a dedicated Atlas machine, with bespoke RAL, NCS, or competitor references matched on the same equipment.
Technical Specifications — Atlas Gemini RS Grey Data Sheet Highlights
| Property | Value |
|---|---|
| Pack size | 25 kg plastic bucket |
| Base material | Siloxane-enhanced resins · 4K mineral aggregates · cellulose fibres |
| Base colour | Grey — tintable to full 480 SAH palette + bespoke RAL / NCS |
| Grain size | 1.5 mm (lambskin texture) |
| Density | ≈ 1.9 g/cm³ |
| Coverage — hand | ≥ 2.3 kg/m² (≈ 10.9 m² per tub) |
| Coverage — machine | ≥ 1.9 kg/m² (≈ 13.2 m² per tub) |
| Vapour diffusion resistance | 0.14 ≤ Sd < 1.4 m |
| Vapour permeability class | V2 (EN 15824) |
| Water absorption class | W2 (EN 15824) |
| Adhesion to substrate | ≥ 0.35 MPa |
| Application temperature | +5 °C to +30 °C (0 °C with Atlas Eskimo) |
| Relative humidity at application | < 80 % |
| Touch-dry | ≈ 15 min (at 20 °C, 50 % RH) |
| Full cure | ≈ 24 h (at 20 °C, 50 % RH) |
| Shelf life | 12 months from manufacture date |
| Standard | EN 15824:2017 · DoP 280/CPR · UKCA |
| BBA system certificate | 13/5018 (Atlas ETICS EPS system) |
How to Apply Atlas Gemini RS Grey — Mixing, Pot Life, Coverage
Each tub arrives ready for the wall, with no dilution, thickening, or proprietary additions to the paste. A 30–60 second power-stir with a low-speed paddle immediately before each load smooths the consistency. The underlying system carries the rest of the performance: a cured reinforced basecoat embedding the Atlas 150 g/m² alkali-resistant mesh, primed with a system-matched quartz primer from the exterior render primer range, releases the 4K aggregate's full self-cleaning, crack-bridging, and biocidal behaviour.
Lay the render across each panel with a stainless-steel trowel at aggregate thickness, returning surplus to the bucket and stirring between loads. Texture immediately with a plastic float, working steady circular motions until the lambskin grain pulls evenly. The 4K formula gives extended open time, so a two-person crew can carry the wet edge across a full storey before the leading band sets; that wet-edge discipline is what eliminates lap marks on the deeper SAH tints this product is built for, where any joint would read in raking light.
- Coverage at 1.5 mm hand: ≥ 2.3 kg/m² — one 25 kg tub covers approximately 10.9 m² on an even basecoat.
- Machine application: 1.5 mm 4K aggregate optimised for professional units with a 6 mm nozzle, ≥ 1.9 kg/m² (≈ 13.2 m² per tub), preferred for commercial elevations above 50 m².
- Line conditioning: run a charge of system-matched primer through the machine hose before render goes through, so the wet interior keeps the first pull clean.
- Open time and re-stirring: ready-mixed — a second 30-second power-stir handles any tub stood over 10 minutes; never add water, retarder, or proprietary mortars.
- Drying window: approximately 15 min surface dry and 24 h full cure at 20 °C and 50 % RH; protect from rain, wind, and direct sun across that window.
Installation Notes — Conditions, Drying Times, Finishing
BBA system performance begins at the primer stage: apply a system-matched quartz primer at least 24 hours before rendering to regulate substrate suction and create the mechanical key the siloxane resins need for lasting adhesion. Pick a working day inside +5 °C to +30 °C with relative humidity below 80 %, and shield the curing render from direct sun, wind, and rain across the full 24-hour cure.
For programmes pushing into autumn or early spring, Atlas Eskimo setting accelerator at 0.25 kg per tub extends the working range to 0 °C and shortens initial set, so the render is less exposed through the longer cold-weather drying window. The full seasonal protocol of temperature thresholds, humidity checks, and forecast routine is covered in the cold-weather rendering timing guide.
- Single production batch: run one batch across each elevation so batch-driven shade drift cannot creep in on a saturated grey-base finish.
- Plan breaks at architectural lines: corners, downpipes, sill lines, and recess details all conceal a joint; mid-panel pauses never do.
- Tool care: rinse tools in clean water immediately at break time.
Pro Tips From UK Installers Using Atlas Gemini RS Grey
Premium BBA-certified renders reward disciplined trade habits, because the technologies inside the tub do their job only when the surrounding system and site programme give them room to work. The tips below reflect what experienced UK applicators do differently when the spec calls for Gemini RS on a high-exposure commercial elevation.
- Keep the system specification BBA-aligned: Certificate 13/5018 covers the complete Atlas ETICS assembly, so substituting a non-system adhesive, primer, or basecoat invalidates the certification — confirm every layer before ordering.
- Budget by application method: price at 2.3 kg/m² hand or 1.9 kg/m² machine and add 10 % for reveals and detailing, so roughly one extra tub per 100 m² covers waste without over-ordering.
- Order to a single production batch: request all tubs for one facade in the same delivery so manufacture dates match, since even minor batch drift is visible on saturated mid-tone and dark SAH shades.
- Approve bespoke RAL or NCS at scale: for non-standard references on the grey base, tint a test tub and apply at full thickness on a 1 m² panel under daylight before committing the full order, because dark shades read very differently at scale than on a chip.
- Plan machine runs for elevations above 50 m²: the 4K aggregate is optimised for a 6 mm nozzle and reaches ≈ 13.2 m² per tub by machine — measurably faster and more consistent than hand application on long unbroken commercial elevations.
How the Grey Base Compares to Gemini RS White
Both Gemini RS bases share the same premium 3D-Flex, Mirror Effect, and Biosec technology stack; only the pigment base differs, and that single difference decides which suits your shade. The table below shows where each fits.
| Variant | Key Spec | When to Choose |
|---|---|---|
| Atlas Gemini RS Grey | Grey base · deep saturation | Charcoals, deep blues, rich terracottas |
| Atlas Gemini RS White | White base · anti-yellowing brightness | Pure whites, creams, light pastels |
Is Atlas Gemini RS Grey Right for Your Project?
- Choose this render if: the project needs certified ETICS compatibility, superior impact resistance, and long-term self-cleaning — Gemini RS Grey is the right specification for commercial buildings, schools, multi-unit residential, and any elevation facing heavy pollution, dense greenery, or high foot traffic, with deeper pigment saturation on mid-tone and dark SAH shades.
- For pure whites and the lightest tints: the Atlas Gemini RS White 25 kg uses the same premium technology stack on a white base that preserves brightness on pastels and pure whites where maximum pigment clarity from the first coat is the priority.
- For moderate-exposure residential elevations: the broader premium silicone render collection includes standard silicone finishes with excellent hydrophobic and vapour-permeable performance at a lower price point, a sensible choice when the premium 4K, Mirror Effect, and Biosec technologies are not essential.
- For plinth and splash zones: pair the Gemini RS finish above DPC with a hard-wearing decorative finish from the mosaic render range to protect ground-level impact areas without compromising the facade.
FAQ — Atlas Gemini RS Grey Coverage, Compatibility, Ordering
How many 25 kg tubs do I need for 100 m² at 1.5 mm grain?
At 1.5 mm hand-applied, consumption starts from 2.3 kg/m², so 100 m² needs a minimum of 230 kg, which is 10 tubs. Adding 10 % for reveals, corner detailing, and uneven substrates brings a practical order to 11 tubs. Machine application is more economical at 1.9 kg/m² (≈ 13.2 m² per tub), so the same area is comfortably covered by 8 tubs plus one spare.
Does the BBA certification cover the whole system?
BBA Agrément Certificate 13/5018 covers the complete Atlas ETICS system, with adhesive, reinforcing layer, primer, and finish coat all assessed together as a single certified assembly. Using system-matched components — quartz primer, Atlas mesh, and the correct basecoat mortar — keeps the certification and any associated warranty valid, giving Building Control a clear compliance pathway for sign-off subject to the project's own fire strategy.
How is Gemini RS different from standard Atlas Silicone Render?
Both share the same silicone-siloxane foundation, V2 vapour permeability, and 1.5 mm lambskin texture, but Gemini RS adds three premium technologies: 3D-Flex elasticity for superior crack bridging, Mirror Effect high-reflectance additives that slow UV pigment fade on darker shades, and Biosec encapsulated biocide that releases gradually over the coat's service life. Gemini RS is also certified within Atlas ETICS BBA system 13/5018, which standard Atlas Silicone Render does not carry, making it the right specification when BBA cover, premium durability, or biological exposure are priorities.
How dark a tint can I specify on the grey base?
The standard reinforcing system supports tints with a Heat Brightness Value above 15 %, and switching the basecoat to a dispersion-adhesive reinforcement extends the range down to HBW 6 %, covering the majority of the deeper SAH shades. For very dark shades on south-facing elevations, confirm with the technical team that the system specification matches the client's warranty terms and the building's movement-margin expectations, because Mirror Effect helps but every dark facade benefits from a sense check before order.
Can Atlas Gemini RS Grey be applied by machine?
Yes — the 1.5 mm 4K aggregate is optimised for professional rendering units with a 6 mm nozzle, delivering a uniform coat at approximately 13.2 m² per tub (≥ 1.9 kg/m²). Machine application is preferred for commercial elevations above 50 m², where it cuts material use and labour time substantially. Hand and machine textures differ slightly, so the two methods should not be combined on the same elevation.
Is Gemini RS environmentally certified?
Gemini RS is a water-based formulation with low VOC content, releasing minimal emissions during application and curing. Atlas confirms environmental performance through a Type III Environmental Product Declaration (EPD), an independently verified lifecycle assessment that architects and developers can reference in BREEAM or other sustainability submissions. Combined with a BBA-expected service life of at least 30 years, each application cycle replaces what would otherwise be multiple repaint or re-render operations.
What colours are available beyond the standard SAH palette?
Beyond the 480 standard SAH shades, the team mixes bespoke colours to order on a dedicated Atlas machine, matching a specific RAL code, an NCS reference, or a shade from another manufacturer's swatch. The warehouse also mixes the Ceresit Colours of Nature range on separate equipment, bringing the combined choice across both systems to over 1,000 standard shades plus bespoke matching. Browse the colour charts and sample catalogues to view both palettes on rendered swatches.
Technical Documentation — Atlas Gemini RS Grey TDS, DoP, BBA