Description
White is the least forgiving finish on a facade. Every lap mark, every shade drift between batches and every shaded corner shows on it, which is why the specification work matters more here than on a charcoal. Atlas declares this render from 2.3 kg/m² by hand and offers it on a white tinting base across the full SAH range.
Where Atlas Gemini RS White Fits on a UK Facade
Atlas Gemini RS Render White 25kg is a ready-mixed thin-coat silicone render consuming from 2.3 kg/m² by hand at up to 1.5 mm grain, specified on elevations exposed to soiling, impact and biological growth. It sits in the premium silicone render range at Renders World, and the manufacturer's data sheet names the conditions it was formulated for rather than leaving them to interpretation.
- Urban and industrial locations — the sheet lists dust, exploitation factors and industrial pollution among the conditions this render is recommended for, which is where a white finish is normally hardest to keep.
- Impact-exposed ground level — playground surrounds, gateways, drive-through openings and parking bays, on the render's resistance to mechanical damage.
- Damp and shaded ground — wetland sites, land near water, close proximity to trees and green areas, and permanently shaded elevations.
Substrate scope is equally explicit. The sheet covers ETICS build-ups on EPS boards, even mineral substrates such as concrete and traditional cement or cement-lime renders, and interior use; for a mineral wool build-up it directs the specifier to the ATLAS ROKER system, which is a decision to settle before the boards arrive on site.
Why Specifiers Choose the White Base
- White tinting base for the pale end of the palette: whites, creams and light pastels reach their intended depth from a white base, and the shade is chosen from the Atlas render colour charts and sample books before any tub is tinted.
- Four-aggregate 4K formula: Atlas credits the four texturing aggregates and fillers with better hold on trowel and wall, quicker texturing without repeat passes, and even aggregate distribution — the property that decides whether a pale panel reads uniform.
- ATLAS 3D-flex elasticity: the formulation is described as compensating summer-to-winter movement and sudden surface temperature change, such as heavy rain landing on a sun-warmed wall.
- MIRROR EFFECT reflectance: Atlas attributes a high light reflection coefficient to the surface, lowering its temperature and protecting the polymer resins and pigments from UV.
- BIOSEC and ATLAS CAPS: biologically active substances release slowly across the coat's service life, which the sheet ties to protection from algae and mould — worth having where growth would be immediately visible.
Technical Data Read From the Gemini RS Sheet
| Property | Declared value |
|---|---|
| Pack | 25 kg plastic bucket |
| Density of the ready product | approx. 1.9 g/cm³ |
| Grain and texture | up to 1.5 mm, baranek (lambskin) |
| Colours | 406 SAH shades |
| Diffusion resistance | 0.14 ≤ Sd < 1.4 m |
| Water vapour permeability | V2 (EN 15824) |
| Water absorption | W2 (EN 15824) |
| Adhesion | 0.35 MPa |
| Consumption, hand | from 2.3 kg/m² |
| Consumption, machine | from 1.9 kg/m² |
| Working temperature | +5 °C to +30 °C |
| Relative humidity | < 80 % |
| Surface dry / dry | approx. 15 min / approx. 24 h at 20 °C, 50 % RH |
| Shelf life | 12 months from the production date |
| Standard and DoP | EN 15824:2017 · DoP 280/CPR |
| Named in system assessments | ATLAS GRIP (ICiMB-KOT 2022/0180 issue 1) · ATLAS ETICS (ITB-KOT-2020/1616 issue 3), both Polish national technical assessments |
At the August 2026 fetch the tub is listed at £63.80 per 25 kg bucket and showing as available, matching the grey base to the penny; no VAT label is displayed, so none is stated here. The working arithmetic runs 25 kg ÷ 2.3 kg/m² = approximately 10.9 m² per tub, so £63.80 ÷ 10.9 m² ≈ £5.85/m² in material alone, before basecoat, mesh, primer and labour. Renders World despatches from Southampton, and the site shipping policy processes in-stock orders the same day with the delivery method confirmed after the order; the render coverage calculator does the full take-off.
Two figures previously published here have been corrected against the manufacturer's sheet: the palette is 406 SAH shades, and the declared adhesion is a flat 0.35 MPa rather than a minimum. Specify from the SAH fan deck, and confirm any bespoke reference on a tinted sample rather than a printed chip.
How to Apply Gemini RS White — Preparation, Stirring, Texturing
- Season and prepare the substrate so it is stable, dry, even and clean, removing any biological growth with a proprietary biocidal wash first — on a white finish this step is visible in the result.
- Prime with ATLAS CERPLAST, the key coat the sheet names for reinforced layers and mineral substrates, stocked in the exterior render primers range.
- Stir, never modify. The paste is ready to use and must not be mixed with other materials, diluted or thickened; stir immediately before use, and at the top of the temperature range the sheet permits up to 1 % clean water.
- Lay at aggregate thickness with a smooth stainless steel trowel, returning surplus to the bucket and re-stirring it before it goes back on the wall.
- Texture with a plastic float in circular motions to pull the baranek grain even; machine-applied render is left untextured.
The reinforced layer beneath carries the structural work, and Atlas 150 is the mesh the manufacturer names in its own reflectance condition — the Atlas 150 g/m² alkali-resistant mesh is the matched roll for that build-up. Panel planning, wet edge and trowel discipline are set out in full in the step-by-step thin coat rendering method.
Installation Conditions, Batching and Drying
- Working window: +5 °C to +30 °C with relative humidity under 80 %, for mix, substrate and air, right through setting.
- Shoulder season: the sheet permits work above 0 °C at humidity to around 80 % after adding Atlas Eskimo setting accelerator, the Atlas-only cold-weather component; the seasonal routine sits in the guide to render application timing in UK conditions.
- Drying: approximately 15 minutes to surface dry, approximately 24 hours to dry at 20 °C and 50 % RH, longer near +5 °C or in high humidity — programme to the slower figure.
- Protection: shield worked and drying surfaces from direct sun, wind and precipitation.
- Batching: the sheet requires one production date across a single surface. On a white base this is the instruction that most repays following, because shade drift between batches has nowhere to hide.
- Joints: work wet on wet and plan breaks at corners, building returns, downpipes and colour changes rather than mid-panel.
- Not for: horizontal surfaces under standing water or snow load, or surfaces wetted by rising damp.
Wash tools in clean water straight after use, and lift hardened residue with the ATLAS SZOP 2000 preparation the sheet names. A float that still cuts cleanly on day three is what keeps a long white elevation reading as one wall.
White Base or Grey Base — How the Two Gemini RS Tubs Differ
| Variant | What differs | When to choose |
|---|---|---|
| Atlas Gemini RS Render White 25 kg | White tinting base | Whites, creams and light shades |
| Atlas Gemini RS Grey 25 kg | Grey tinting base | Mid-tone and deep SAH shades |
One data sheet covers both tubs and declares one set of properties for ATLAS GEMINI RS. So the choice is a tinting decision, not a performance one: take the base that reaches your shade in the fewest passes, and V2 permeability, W2 absorption and 0.35 MPa adhesion arrive with either. Both are listed at the same price this month, which keeps the decision purely technical.
How to Specify Gemini RS White on a UK Project
BBA Agrément Certificate 13/5018, Product Sheet 1, lists the finishing coats of the Atlas/Aval EPS system as Atlas Cermit Mineral, Atlas Acrylic Render, Atlas Acrylic-Silicone Render, Atlas Silicone Render, Atlas Silicate Render and Atlas Silicone-Silicate Render. Gemini RS is not among them. Its documented system credentials are the two Polish national technical assessments printed on its own data sheet.
- Where BBA system cover is a project requirement, specify one of the finishing coats the certificate actually names — they sit beside this tub in the wider thin-coat render collection, so switching costs nothing in lead time.
- Where the shade is pale, the reflectance conditions the sheet attaches to intensive colours do not bite, which is the practical advantage of working from the white base: the basecoat specification stays open.
- Where a scheme mixes pale field colour with a deep accent, the accent is where the conditions apply — the guidance on dark render shades and solar exposure covers the reflectance thresholds and the basecoats they depend on.
- Where the render itself is still undecided, the silicone render buying criteria compared set out how binder, grain and certification are weighed against project type.
- To order, take the 25 kg white base tub for your SAH shade and allow roughly one extra tub per 100 m² for waste; the grey base handles anything mid-tone or darker.
FAQ — Coverage, Compatibility and Certification
How many 25 kg tubs cover 100 m²?
Hand application starts at 2.3 kg/m², so 100 m² × 2.3 kg/m² = 230 kg, and 230 kg ÷ 25 kg = 9.2, rounded up to 10 tubs. Adding 10 % for reveals and detailing gives 253 kg ÷ 25 kg = 10.1, so 11 tubs is the sensible order.
- By machine: 100 m² × 1.9 kg/m² = 190 kg ÷ 25 kg = 7.6, so 8 tubs plus a spare.
- Caveat from the sheet: the declared consumptions apply to even substrates, and the reliable figure comes from a trial patch on the wall in front of you.
What does the sheet require underneath?
ATLAS CERPLAST is the named key coat for reinforced layers and mineral substrates, and the seasoning times are specific: minimum one day for a reinforced layer built with ATLAS ETICS mortars, minimum three days for one built with ATLAS GRIP U, minimum seven days per centimetre for new cement renders at 4 % moisture, and minimum 28 days for concrete with structural moisture below 4 %.
Can hand and machine application be combined on one building?
Spraying is supported through 6 mm nozzles on the units the sheet names, with sprayed render left untextured. Because hand and machine develop the surface differently and can read as a slight colour difference — most visible on pale shades — the sheet rules out combining the two technologies on one building. Fix the method before the first elevation.
Does the sheet say anything about yellowing?
It does not use that word, and no anti-yellowing claim is published here. What it does declare is the MIRROR EFFECT high reflectance coefficient, which Atlas links to a lower surface temperature and to protecting the polymer resins and pigments from UV, plus BIOSEC biocide against algae and mould. Those are the documented mechanisms behind a white facade holding its appearance, and specifying a system-matched build-up is what lets them work.
Is this render covered by BBA Agrément 13/5018?
No, and none is claimed here. The certificate's component list names six other Atlas finishing coats and does not include Gemini RS. Its documented credentials are the ATLAS GRIP and ATLAS ETICS national technical assessments on its data sheet, and where a UK specification asks for BBA cover, the certificate's own listed finishes are the direct route.
How is an aged Gemini RS facade refreshed?
The sheet's renovation route is repainting with a silicone masonry paint from the ATLAS SALTA family — SALTA, SALTA N or SALTA N PLUS. That keeps a tired elevation on a documented pathway, and it is a repaint rather than a re-render.
Technical Documentation