Exterior Wall Paint, Lime Silicate, Colours - Heritage Graphenstone GCS Exterior
Grafclean Natural Eggshell Colour Chart - Graphenstone
Graphenstone Natural Exterior Masonry Wall Paint Colour Charts
Exterior Wall Paint, Lime Silicate, Colours - Heritage Graphenstone GCS Exterior

Exterior Wall Paint, Lime Silicate, Colours - Heritage Graphenstone GCS Exterior

Universal exterior lime based natural paint for lime render, brick, old paints, brick, mortar, concrete and many others. Ideal for walls with multiple surface types or tricky substrates.

Graphenstone GCS Exterior is perfect for restoration works, especially on older or historic buildings that need to be able to breathe. Made from a perfect mix of lime, silicate and other natural mineral bases and offers a gorgeous matt finish.

Highly breathable (<0.08 SD value), natural and very low VOC (<1g/l) with amazing coverage (12-18m2 per litre), and best in class really!

This is an excellent heritage paint, endorsed by English Heritage themselves- who have their own selection of 24 English Heritage Colours in this very paint.

Colours: Available in the majority of the gorgeous 120 paint colours from Graphenstone. Order a Graphenstone Colour Chart here.

Samples & Testers: All new colours available to sample as A5 Peel & Stick Colour Swatches, which can be ordered in the standard range of Grafclean Emulsion. We hold samples in white GCS exterior only so you can check texture, but for all colour samples just order in the Grafclean Emulsion - the colours are the same. (Interior version also available)
Price
£36.00

Why us? We help people choose genuinely safer paints and finishes, without the greenwashing. We’re an independent shop, not a paint brand, and we only recommend products we truly believe in, or have tested and tried. For us, this is personal: better indoor air quality matters. Don't just take our word for it, read our Reviews. What is a natural paint?

Available in a number of colours from the 120 colour range colour chart.

Especially suited for restoration of heritage and listed buildings, due to the compatibility and high breathability of this natural paint.

Specifications

Perfect for all exterior walls.
High covering power
Ultra Matt finish (3% sheen)
Very Low VOC, < 1 g/l
VOC emission: Class A+
Fire rating: EU A2 s1, d0 (EU EN13501-1), Class 0 (British Standard)
Cradle to Cradle Certified SILVER
GreenRate Certified: Level A
Very Breathable, SD value: <0.08
Certified for moisture control
Tough and long-lasting
Excellent Washability: Class 1
Excellent flexibility - a non-cracking formula
High adherence to substrates

Drying: GCS exterior dries in 2-4 hours between coats, and 24 hours until fully dried. Around 30 days until fully cured.

Coverage: Around 12-18m2 per Litre. We recommend diluting 10-15% with water before application for better coverage and easier application. Requires 2 coats.

If painting over mineral substrates, they must be at least 28 days old before application. The substrate must also be resistant to high alkalinity. If in doubt apply to a test area first, and do not apply to surfaces in constant contact with water.

Primer: The correct primer is mostly required for all exterior use of GCS Exterior. Please use the L42 Ambient Primer. This hybrid primer stabilises the surfaces without compromising on breathability.
The primer covers at 26-30m2 per litre, and only 1 coat is required, it's super economical.

Use the L42 Ambient Primer when painting on:
- New renders & Lime renders
- Older surfaces such as lime wash
- Old unknown masonry paints

How to prep GCS Exterior prior to using

Open pot and give it a good stir. Ideally dilute with 10%-15% of the product weight, which will be around 150ml to 200ml of water per litre of product). Avoid shaking to avoid bubbles. 

Apply two to three even coats, with a roller, brush or airless spray gun. 

Data Sheets

- Main GCS Exterior 'How To' Data Sheet - Read this one!
- Graphenstone Heritage Leaflet
- MSDS GCS Exterior M Base
- MSDS GCS Exterior P Base
- GCS Exterior One Pager

Enviro Certifications
- Cradle to Cradle Silver Certificate
- Global Green Tag Level A Certificate
- GreenTag Health Platinum Certificate
- Sensitive Choice Approved Asthma Friendly Certificate
- Environmental Product Declaration (verified and registered document that communicates transparent and comparable information about the life-cycle environmental impact of products. The International EPD® System is a global programme for environmental declarations based on ISO 14025 and EN 15804)

Does GCS exterior ALWAYS require L42 on exterior lime (either old or new)

New Lime requires either 1 x Coat L42 or a Mist Coat of Naturcolour or a Mist Coat of the Topcoat. Existing Lime based coatings may be ok without a Primer coat but we recommend L42 as it helps stabilise the surface.

Does GCS interior ALWAYS require L42 on interior lime (either old or new) As above

Does GCS interior ALWAYS require L42 on interior gypsum (either old or new)

We don’t recommend L42 for use on bare Gypsum Plaster, either a Mist Coat of Naturcolour or the of the Topcoat.  

Does GCS interior ALWAYS require L42 on interior standard painted non lime

Not always but L42 is recommended if there is very old, unstable or multiple different types of Paint finish as it regulates the absorption. Good condition existing paint is usually fine to go straight on with two coats but for big colour changes a coat of Nevada can help and be more cost effective.

What does Pastel, Medium or Transparent mean on the side of the pot?

This is just the base paint used to match the pigments used to create the colour chosen. We open the base pot and tint directly into it, mix and reseal and send to you.