Eco Outdoor Wall Paints - Quick Guide

Environmentally friendly exterior masonry paint. Whether you are looking to waterproof a wall or need a breathable outdoor wall paint we have a solution for you in a colour you'll love.

This guide is intended as a quick reference only. Please always read datasheets and instructions before applying (and preferably before purchasing!). If in any doubt at all about what environmentally friendly external masonry paint finish you could use on your project, please do contact us. We are always happy to help.

When you need a breathable exterior masonry paint

A quick note about "breathable paint". For building physics a "breathable paint" is a finish that will allow the water vapour to permeate, travel or transfer through it (it is microporous). The basic premise of a truly breathable paint is its ability to allow water vapour to evaporate from the surface and not prevent this transfer to be slowed or stopped entirely. This allows the walls to "breathe" and therefore reduces the likelihood of problems associated with damp, like mould, mildew and condensation.

Buildings that are likely to require breathable wall paints are ones built using traditional techniques and materials, for example, buildings with solid walls (ie not cavity walls). Older buildings and new eco-builds are likely to need "breathable paints" too.

Lime wash

Limewash is only suitable for previously limewashed surfaces or for painting directly onto mineral surfaces.

Lime wash is a traditional painting medium that allows the painted surface to breathe and is therefore a great choice for traditional buildings and new eco-builds alike.

Cheaper than other breathable exterior wall paint options, it's main disadvantages are that it often requires 4 or more coats when painting on bare surfaces and will need maintaining (lime washing) every 1 to 3 years depending on the location of the building.

Limewash options include:

• Auro 344 Natural Lime Paint
• St Astier Lime Paint
• Lime Putty with Limewash Pigments (pictured)

Earthborn Silicate Masonry Paint

EcoPro Silicate Masonry Paint is a highly durable mineral paint that dries to a classic, matt finish. Being highly breathable yet water repellent it offers an alternative to traditional lime based coatings.

Available in 24 colours, like limewash it must be used on mineral surfaces and is not suitable for application over conventional "plastic" masonry paints.

It is a three coat system that requires a primer, however the Silicate Masonry Paint from Earthborn has a lifespan of up to 15 years and is therefore a great investment especially when taking into account the cost of hiring scaffolding etc.

• Read more about the Earthborn Silicate Masonry Paint System here

Graphenstone Exterior Masonry Paint

Unique in their use of Graphine in the paint range, Graphenstone combine natural minerals such as lime and silicate with innovative Graphine technology, to create very durable, breathable and low maintenance paint finishes.

• Biosphere Exterior combines Graphine with pure lime paint to give a natural matt finish that’s tough and long lasting. It can be applied over previously painted and unpainted surfaces. Two coats are required although unpainted surfaces should be primed with a coat of Graphenstone primer first. Biosphere is available in pure lime white plus 13 pastel shades.
• GCS Exterior combines Graphine with lime, silicate and natural minerals. It’s particularly suited to restoration projects, heritage and listed properties and gives a traditional matt finish with a slight mineral texture. Suitable for all types of surfaces including mortar, brick, concrete and old paints; it should be prepped with GCS Primer, followed by 2 coats of GCS Exterior. Available in 44 colours plus White.
• Grafclean Exterior mineral paint (pictured) is made with a revolutionary natural vegetable resin. It has an ultra matt finish and performs more like an acrylic type paint, which means it can be applied to most types of substate - perfect for modern day buildings. GrafClean can be applied directly over painted and unpainted surfaces although absorbant surfaces should be primed beforehand. GrafClean Exterior is available in White as well as 57 colours.

Keim External Masonry Paints

Keim environmentally friendly mineral paints have until recently only been available to the trade. Celtic Sustainables is the only Keim Paint retailer in the UK!

Usually specified by Architects, paints in this range are expected to last for at least 15 years in terms of aesthetics and performance. 

Available in hundreds of different colours, it is a tricky range to get your head around as there are many different factors that determine which product to go for. Often a pre-treatment coat is required too.

Unless Keim has been specified by a professional for your project, we suggest that you contact us before purchasing so we can help you navigate through the various options available to you.

Keim External Masonry Paints include:

• Keim Soldalit (pictured) - for mixed substrates including previously painted walls
• Keim Royalan - for harsh environments eg coastal locations
• Keim Soldalit-ME - to help reduce airbourne pollutants
• Keim Lotexan - provides a clear hydrophobic (waterproof) finish excellent for stonework and bricks
• Keim Granital – Extremely durable, vapour permeable and lightfast. For all forms of unpainted mineral substrates.

When you don't need a breathable exterior masonry paint

Eco Exterior Wall Paints

Tough and hard wearing these paints are all in some way better for you or the environment than other comparable "high street" non-breathable paint brands.

Not designed for buildings that need to breathe as they have some acrylic (plastic) content, but they can go over other acrylic based paints. May require a primer if used on bare surfaces.

Options are:

• Eico Alterior Matt Emulsion

Environmentally Friendly Masonry Paint

View our entire range of Environmentally Friendly Masonry Paint.

[article first published June 2019, updated April 2020]