Silicate paint vs acrylic
Updated: 23 October 2026
A £30 tub of conventional masonry paint and a £130 mineral tin force a choice about how the wall handles moisture. Silicate paint vs acrylic comes down to whether the masonry needs to dry outward or already wears a stable modern plastic film. Acrylic suits a sound film on a modern cavity wall. Bare solid brick and lime render need a vapour-open mineral system. The four Earthborn packs are in our [silicate paint comparison](/hub/paints-and-varnishes/silicate-paint). Peter F. updated this page on 23 October 2026. Our amazon.co.uk links may earn a commission at no extra cost to you.
A £30 tub of conventional masonry paint and a £130 mineral tin force a choice about how the wall handles moisture.
A £30 tub of conventional masonry paint and a £130 mineral tin force a choice about how the wall handles moisture. Silicate paint vs acrylic comes down to whether the masonry needs to dry outward or already wears a stable modern plastic film. Acrylic suits a sound film on a modern cavity wall. Bare solid brick and lime render need a vapour-open mineral system. The four Earthborn packs are in our silicate paint comparison. Peter F. updated this page on 23 October 2026. Our amazon.co.uk links may earn a commission at no extra cost to you.
Our top picks
| Badge | Product | Over acrylic | Primer on the listing | Listed coverage | Note | Price | Offer |
|---|---|---|---|---|---|---|---|
| Best overall |  Earthborn Earthborn Ecopro 5 L white | With bonding primer | Silicate or bonding | 5–7 m²/L | 8.6 | about £130.00 | View offer |
| Best value |  Earthborn Earthborn Ecopro 10 L white | n/a | n/a | n/a | 8.2 | about £248.75 | View offer |
| Alternative |  Earthborn Earthborn Ecopro 5 L Sandstone | With bonding primer | Silicate or bonding | 5–7 m²/L | 8.0 | about £145.00 | View offer |
On this page
Two different coatings
Acrylic masonry paint forms a continuous plastic film. Potassium silicate paint petrifies into bare brick, stone or lime render, if the wall is free of old film-forming paint. Under DIN 18363, Earthborn Ecopro Silicate Masonry Paint uses potassium silicate as its main binder with less than 5% organic acrylic polymer, and volatile organic compounds stay below 0.5 g/l. The UK Volatile Organic Compounds in Paints, Varnishes and Vehicle Refinishing Products Regulations 2012 set a 40 g/l ceiling. A low-VOC figure does not by itself make a tin breathable.
On an exposed 225 mm solid brick gable, hairlines in an acrylic skin let rain in and slow evaporation out. A mineral coat at pH 11.2 to 11.4 stays open to vapour. Wear safety glasses and gloves.
Where a cheap masonry tin is the wrong wall
Cheap masonry paint on a solid wall or a lime-rendered cottage traps moisture, unless the building has a modern ventilated cavity and a dry interior. Class V1, high water-vapour permeability, means an sd value below 0.14 metres. Earthborn’s 2026 sheet records 0.01 metres for Ecopro Silicate Masonry Paint, about 1,515 g/m² of water vapour in 24 hours. If a seller calls an acrylic solid-wall friendly without a test figure, ask for the sd value. Waterproof claims often confuse rain resistance with vapour permeability.
On a rubble-stone cottage, thick acrylic applied in October can blister by February as trapped moisture freezes. On a post-1970 brick-and-block house with a sound acrylic film in a sheltered street, another acrylic coat is sensible maintenance.
Stay, bridge, or strip
You cannot brush potassium silicate straight over acrylic. The binder needs an absorbent mineral face. Over sound existing paint, Earthborn Bonding Primer covers 4 to 7 m² per litre and can be recoated in 4 to 6 hours. It does not restore a bare-wall sd value. The primer is Class 2 at 0.35 metres, about 59.9 g/m² in 24 hours, and the old acrylic underneath stays the bottleneck.
Earthborn puts a full mineral build on bare masonry at 15 to 20 years, and a Bonding Primer bridge at 5 to 10 years. Coat order is in how to apply silicate paint. Fresh lime is not a Bonding Primer job: see silicate paint for lime render. On a listed facade, swapping limewash for silicate can need consent, and Scotland can differ.
What the price gap is paying for
On amazon.co.uk on 21 October 2026, 5 litres of Earthborn Ecopro Silicate Masonry Paint in white cost £130. A typical Sandtex 5 litre masonry tin sat near £30. Primers and two coats belong in the budget, so a 30 m² gable costs more than one acrylic refresh.
Use the full silicate system on bare brick, stone or cured lime render that must stay vapour-open. Keep acrylic if the cavity wall already has a sound plastic film that does not trap damp. Silicone resin is a different binder, in the silicate paint buying guide. Pack sizes are in best silicate paint.
Common questions
Is acrylic masonry paint a problem on every house?
Acrylic masonry paint is not a problem on every British home, provided the wall is a modern cavity construction and the existing film is sound and dry. On sheltered modern brickwork, an acrylic refresh maintains the colour. The trouble starts when a low-permeability film goes onto solid nine-inch brick, soft stone or lime render that relies on outward evaporation.
Can I paint silicate straight over acrylic?
You cannot apply potassium silicate masonry paint directly over an existing acrylic coating, because the mineral binder needs direct contact with bare brick, stone or render to form a chemical bond. Applied straight onto a plastic film, silicate paint fails to bind and can flake or wash away. To coat over sound existing acrylic without stripping the wall, apply a mechanical bridge such as Earthborn Bonding Primer first.
Does Bonding Primer make an old acrylic wall breathable?
Earthborn Bonding Primer over old acrylic does not restore the high breathability of bare masonry or make the existing plastic film vapour-open. Earthborn Silicate Masonry Paint has an sd value of 0.01 metres. Bonding Primer has a medium permeability sd value of 0.35 metres, passing roughly 59.9 g/m² of vapour in 24 hours. Any conventional acrylic left beneath the primer still restricts moisture movement.
Is it worth paying £130 for 5 L when standard masonry paint is near £30?
Paying £130 for 5 litres of Earthborn Ecopro Silicate Masonry Paint on amazon.co.uk is worth it on bare solid masonry or cured lime render that needs Class V1 vapour openness. With Silicate Primer, the maker states 15 to 20 years. If the wall already has sound acrylic you will not strip, a £30 acrylic tin is usually the more practical spend.
What sd value should I ask for when comparing masonry paints?
Ask the manufacturer for the sd value, the water-vapour diffusion-equivalent air layer thickness, tested to EN ISO 7783. Specifier guidance classifies a coating as high vapour permeability (Class V1) when its sd value sits below 0.14 metres. Earthborn Ecopro Silicate Masonry Paint lists an sd value of 0.01 metres. Its Bonding Primer sits in the medium band at 0.35 metres.
Will switching to silicate paint cure rising damp?
Switching from acrylic to silicate paint will not cure rising damp or fix structural water from leaky gutters, cracked flaunching or a bridged damp-proof course. Once a trapping acrylic film is stripped and a vapour-open mineral system goes on, damp masonry can evaporate moisture outward more freely rather than blistering a paint skin. The source of ground or plumbing moisture still needs a physical repair before you redecorate.
Related pages
Sources
Public sources from the research digest, last checked on 22 October 2026. Shelf prices and the one star line are the amazon.co.uk figures in the display file, dated 21 October 2026. The price band is this set, not a market average. No listing was lab-tested.
- VOC Regulations 2012 (retrieved 22 October 2026)
- Keim: silicate paints (retrieved 22 October 2026)
- Keim Soldalit (retrieved 22 October 2026)
- Keim application notes (retrieved 22 October 2026)
- Earthborn Silicate Masonry Paint data sheet 2026 (retrieved 22 October 2026)
- Earthborn FAQs (retrieved 22 October 2026)
- Earthborn silicate paint safety data sheet 2022 (retrieved 22 October 2026)
- Historic England: redecorate (retrieved 22 October 2026)