Description
Atlas Salta Base Grey 10 L is the grey-base silicone facade paint formulated for the deep end of the SAH palette — its darker tinting base drives full opacity in charcoal, slate, and anthracite shades in fewer coats than a white base, while delivering the same self-cleaning W3, V2-breathable film to EN 1062-1.
Where Atlas Salta Base Grey Performs Best — Dark and Saturated UK Facades
Atlas Salta Base Grey is a 10-litre silicone-polymer masonry paint engineered for the mid-tone and darker end of the SAH palette, its grey tinting base carrying deeper pigment loading so charcoal, slate, and deep earth tones reach full saturation without the extra passes a white base demands. Held within the silicone masonry paints range, it shares the Pearl Effect self-cleaning surface, W3 low water permeability, and V2 vapour permeability to EN 1062-1:2004 with its white sibling — the base is the only variable, and on a dark specification it is the variable that decides coverage.
The grey base earns its place whenever the specified colour sits in the lower-reflectance half of the palette, where a white substrate would telegraph through and force a third coat. On the contemporary anthracite and slate facades increasingly specified across UK new-build and renovation, the grey base delivers even, deep colour that installers consistently report reaching full opacity in two coats rather than three.
Why Trade Specifiers Choose Atlas Salta Base Grey
- Deep colour in two coats, not three: The grey base's higher pigment loading masks dark and saturated SAH shades efficiently, so charcoal and slate reach uniform opacity in two coats — cutting a full pass of labour and material against a white base on the same colour.
- Self-cleaning Pearl Effect surface: The microscopically smooth silicone film resists dirt adhesion, so rainwater lifts dust, algae spores, and pollutants as it sheets off — keeping a dark facade, where dust and salts show most, looking freshly painted for years.
- Walls breathe while rain stays out: An Sd below 0.14 m (V2) lets the masonry release moisture, while W3 water absorption keeps driven rain on the surface — the breathe-and-shed combination that protects solid-wall and EWI retrofits under dark finishes.
- Elastic film handles thermal movement: Dark colours run hotter under sun, and the flexible silicone-polymer binder absorbs the wider thermal swings a deep facade experiences without the micro-cracking that admits water into rigid paints.
- Built-in bio protection: Low water absorption plus silicone surface chemistry discourages algae and fungal growth on north-facing and sheltered elevations where dark tones would otherwise show colonisation soonest.
- Low VOC for occupied buildings: At 39.9 g/L the paint sits below the 75 g/L UK threshold for masonry paints, so a dark facade repaint proceeds safely on occupied homes, schools, and care buildings.
Technical Specifications — Atlas Salta Base Grey Data Sheet Highlights
| Property | Value |
|---|---|
| Binder type | Modified silicone-polymer dispersion (silicone resin + siloxanes) |
| Pack size | 10 litres (approx. 15 kg) |
| Colour base | Grey (tintable to mid-tone and dark SAH colours) |
| Density | Approx. 1.45 kg/dm³ |
| VOC content | 39.9 g/L (EU limit 40 g/L) |
| Gloss level (EN 1062-1) | G3 — matt |
| Dry film thickness (EN 1062-1) | E3 — 100 to 200 µm |
| Vapour permeability (EN 1062-1) | V2 — medium (Sd < 0.14 m) |
| Water permeability (EN 1062-1) | W3 — low (< 0.1 kg/m²·h⁰·⁵) |
| Coverage — mineral renders | ~4.0 m²/L per coat |
| Coverage — dispersion renders | ~5.0 m²/L per coat |
| Coverage — traditional plasters | ~7.0–8.0 m²/L per coat |
| Application temperature | +5 °C to +30 °C (from 0 °C with Atlas Eskimo) |
| Drying / recoat | 2–6 h dry · ~6 h recoat at +20 °C / 50% RH |
| Application method | Roller, brush, or airless spray |
| Shelf life | 12 months (sealed, +5 °C to +30 °C) |
| System approvals | ATLAS ETA 06/0081 · ROKER ETA 06/0173 · ETICS FPC-ITB-0562/Z |
How to Apply Atlas Salta Base Grey — Coverage, Coats, and Dark-Shade Consistency
Atlas Salta Base Grey applies ready to use in two coats by medium-pile roller, brush, or airless spray, with substrate and air temperature held between +5 °C and +30 °C through drying. The coverage number to plan on is around 4.0 m²/L per coat on 1.5 mm grain silicone render, so a 10-litre bucket delivers roughly 40 m² per pass — and because dark shades reveal application inconsistency more than pale ones, keeping a wet edge and even film thickness matters more on grey work than on white.
- Fresh mineral renders: First coat diluted up to 0.20 L water per 10 L, applied direct from five days after rendering (this coat self-primes); second undiluted after ~6 hours, worked perpendicular to fill texture completely.
- Cured dispersion and silicone renders: Allow seven days' cure, then apply both coats undiluted.
- Traditional cement-lime plasters: Allow two to four weeks curing, rewarded with 7.0–8.0 m²/L on smoother surfaces.
- Batch-mix for dark uniformity: Box all buckets for one elevation together before starting — subtle tint variation between separately mixed dark buckets shows far more readily than in pale shades under raking light.
For the full roller technique, dilution ratios, and weather windows, the silicone masonry paint application guide covers the process end to end. Because deep colours carry a thermal consideration on exposed elevations, the dark colours and solar heat guide explains the reflectance thresholds and orientation guidance worth reading before finalising an anthracite or charcoal specification.
Installation Notes — Conditions, Drying, and Dark-Finish Detailing
Plan technological breaks at natural building lines — corners, downpipe runs, colour transitions — so each elevation completes wet-on-wet, which matters most on dark colours where a dry edge catches the eye instantly. Protect fresh paint from direct sun, wind, and rain during application and for at least 24 hours after; on dark shades in summer, working the shaded side of the building and following the shadow round also keeps the film from skinning before it lays off evenly.
The paint crusts within about two hours at +20 °C / 50% RH and reaches full water resistance after six. On old renders allow at least 48 hours of dry weather after the last rainfall before starting. For deep colours on south- and west-facing walls, checking the shade's reflectance against the solar-heat guidance is a step worth getting right at specification stage, since the deepest tones perform most comfortably on sheltered or shaded elevations.
Pro Tips From UK Installers Using Atlas Salta Base Grey
Experienced decorators consistently report that dark facades reward a little more discipline than pale ones, and these habits are what deliver an even deep finish.
- Box every bucket before the first coat: Dark tints show batch variation that pale shades hide, so combining all buckets for an elevation into one working supply guarantees a uniform charcoal or slate across the whole wall.
- Keep a wet edge religiously: Deep colours reveal lap marks that vanish on white, so reload at shadow lines and never let a panel edge dry before the adjoining pass meets it.
- Read reflectance before promising a south wall: The deepest shades run hottest, and confirming the colour suits the orientation — or reserving it for a shaded elevation — protects the finish for the long term.
- Prime chalky substrates regardless of the self-priming claim: A half-day priming with a render primer evens absorption so a dark colour develops uniformly rather than patchy where suction varies.
- Dose Eskimo per bucket in winter: Adding the accelerator to the working batch keeps set times consistent across the elevation instead of one bucket racing ahead.
Is Atlas Salta Base Grey Right for Your Project?
Base Grey is the right choice when you are painting a sound rendered or plastered facade in a mid-tone, dark, or saturated SAH colour and want the deep shade to reach full opacity efficiently while keeping the self-cleaning, breathable silicone performance. The table below shows how it sits against its Base White sibling so you match the base to the shade.
| Variant | Key Spec | When to Choose |
|---|---|---|
| Atlas Salta Base Grey 10 L | Grey base · deeper pigment loading · W3 · V2 | Charcoal, slate, anthracite, deep tones |
| Atlas Salta Base White 10 L | White base · brightest opacity · W3 · V2 | White, pastel, light mid-tone shades |
- Specifying a deep shade on a sun-exposed elevation? The dark colours and solar heat guide linked above sets out the reflectance thresholds and orientation guidance for anthracite and charcoal facades.
- Painting in winter or transitional weather? The Atlas Eskimo accelerator extends the working window down to 0 °C and 80% humidity, covering most UK winter days outside frost events.
- Weighing silicone against acrylic? The silicone paint vs acrylic comparison confirms the right technology for the project's exposure profile.
FAQ — Atlas Salta Base Grey Coverage, Compatibility, Ordering
How many litres of Base Grey do I need, and does a dark colour need more?
Coverage matches the white base at approximately 4.0 m²/L per coat on 1.5 mm grain silicone render, so a 10-litre bucket covers around 40 m² per pass. The advantage of the grey base is that it reaches full opacity on dark shades in two coats where a white base under the same colour often needs three — so for a 60 m² charcoal elevation, plan roughly 30 litres (three buckets) for two coats rather than the 45 litres a white base could require. Add one extra litre per 40 m² for waste and cutting-in.
Why does a dark colour need the grey base rather than the white?
Tinting a deep colour over a bright white base leaves the white fighting the pigment, so the shade looks patchy or washed until enough coats build over it. The grey base starts closer to the target tone, so the pigment develops evenly and reaches full saturation faster — fewer coats, more uniform colour, and better hiding on textured render. For charcoal, slate, anthracite, and deep earth tones, the grey base is the efficient specification; for whites and pastels the white base is correct.
Are dark colours safe on an insulated or south-facing facade?
Dark shades perform reliably when matched to the right elevation, and the silicone binder's elasticity handles the wider thermal movement a deep colour experiences. Each SAH shade carries a reflectance value, and the deepest tones sit most comfortably on sheltered, north-, or east-facing walls; for a dark colour essential on a south- or west-facing elevation, confirming the reflectance against the solar-heat guidance ensures the finish stays sound. On EWI systems specifically, this reflectance check at specification stage keeps the render build-up within its designed thermal range.
Can I apply Base Grey over an existing painted facade?
Base Grey applies successfully over sound, well-bonded coatings — silicate, silicone, and acrylic masonry paints all serve as substrates when the film is intact and free from chalking, flaking, or growth. Going darker over an existing lighter colour is exactly where the grey base earns its place, covering the old tone in fewer coats than a white base would. Where the existing coating is failing, remove it to sound masonry and prime before painting; on mixed-condition elevations, treat failing zones as new substrate and sound zones as paint-on-paint, subject to a condition assessment.
Can I apply Base Grey in winter or cold weather?
Standard application needs a minimum substrate and air temperature of +5 °C. Adding Atlas Eskimo accelerator extends the range to 0 °C and above 80% RH, covering most UK winter working days outside frost events. Paint applied in the morning at 3–5 °C reaches a handleable state by mid-afternoon, keeping multi-coat programmes moving without the week-long delays conventional paints need in the cold — useful on dark elevations where consistent between-coat timing keeps the finish uniform.
Technical Documentation — Atlas Salta TDS and System Approvals