This guide is designed to answer the real questions homeowners, landlords, architects, and property professionals ask before choosing spray cork. It explains what spray cork is, how it works, where it performs best, how much it costs, how it compares to render and external wall insulation, and how to make sure it is installed correctly using a genuine, certified system.
Credibility note: Spray Cork UK are the sole UK supplier of ReveCork. They supply the product, run installer training, and connect customers with approved professionals through their Spray Cork Contractors network.
If you would like a shorter overview first, see The Complete Guide to Spray Cork Insulation in the UK.
Spray cork is a specialist cork-based coating applied using spray equipment to create a seamless, continuous layer across walls or ceilings. Once cured, it forms a flexible, breathable surface that supports thermal comfort, protects against weather exposure, and helps reduce ongoing maintenance.
Unlike traditional render systems or rigid insulation boards, spray cork is applied as a coating rather than a panelled system. This allows it to conform to uneven surfaces, bridge minor cracks, and move with the building over time.
Spray cork can be used externally or internally, depending on the performance goal. Externally, it is often used to protect and upgrade façades. Internally, it can be used as part of a breathable thermal upgrade, particularly in older buildings.
Spray cork is primarily made from natural cork granules combined with water-based binders. Cork is harvested from the bark of cork oak trees without harming the tree itself, making it a renewable and sustainable material.
Cork’s cellular structure contains millions of tiny air pockets. These pockets are what give cork its natural insulating, acoustic, and vibration-dampening properties. When sprayed as a coating, these properties are distributed evenly across the surface.
The finished system is vapour permeable, flexible, and resistant to harsh environmental conditions, including UV exposure and salt air.
Spray cork works by forming a continuous micro-insulating layer over the surface of a building. Cork’s natural structure slows the transfer of heat while the coating remains breathable.
On thermal projects, spray cork can reduce heat loss by up to 35 percent. In real terms, this can translate into approximately 12 to 15 percent savings on energy bills, depending on the building type, heating system, and usage patterns.
Unlike impermeable coatings, spray cork allows moisture to escape. This is particularly important for solid wall properties and older buildings where trapped moisture can cause long-term damage.
Externally, spray cork is commonly used to upgrade façades, protect exposed walls, and extend the life of existing render. It is particularly popular in coastal and weather-exposed locations.
Internally, spray cork can be used as part of a breathable thermal strategy, often alongside materials such as cork plaster. Internal applications are commonly chosen where changing the external appearance of a building is not possible.
Spray cork is not a one-size-fits-all solution, but it performs particularly well in certain scenarios.
Spray cork pricing is bespoke and varies from project to project. There is no single fixed price per square metre because each installation depends on preparation, access, surface condition, and the intended outcome.
In practice, spray cork is priced based on the time, preparation, and material coverage required to achieve the correct finish and performance, rather than a simple flat rate.
Two properties of the same size can have very different spray cork costs. The most common factors that affect pricing include:
When comparing costs, it is important to look at what is included and what work is avoided.
One of the biggest cost advantages of spray cork is overspray. Where existing render is structurally sound, spray cork can be applied after preparation without removing the original surface.
As a comparison:
In overspray scenarios, homeowners avoid the cost of hack-off, waste removal, and full replacement, while gaining additional benefits such as flexibility, breathability, weather protection, and thermal performance.
This is why spray cork is often considered a cost-effective upgrade when existing surfaces are in reasonable condition.
Cost alone does not tell the full story. Breathability, maintenance, and invasiveness all play a role.
| System | Typical cost per m² | Breathability | Maintenance | Invasiveness | Best for |
|---|---|---|---|---|---|
| Traditional render | From £70 | Lower | Higher | Moderate | Standard façade replacement |
| Spray cork | £85 to £140 | High | Low | Low | Breathable performance upgrade |
| External wall insulation | £145 to £185 | System dependent | Varies | High | Maximum insulation build-up |
Overspray is one of the key advantages of spray cork. Where existing render is sound, spray cork can be applied directly after preparation.
This avoids the cost and disruption of hack-off and replacement. In many cases, overspray is significantly cheaper than replacing render while delivering additional flexibility and performance benefits.
Spray cork combines reduced energy demand with lower maintenance costs. Installations are typically supported by a 15-year warranty, with testing showing durability beyond this in harsh environments.
Spray cork has been tested in demanding conditions, including offshore and coastal environments. Maintenance is minimal and usually limited to occasional rinsing with clean water.
Spray cork is often suitable for heritage properties due to its breathability and non-invasive nature. Each building should be assessed individually.
Planning permission may be required when changing the appearance of a brick façade or working on listed or conservation properties. Local authority guidance should always be checked.
Spray cork is a specialist coating system with specific material content and application requirements.
Spray cork improves performance but does not replace every insulation system in every scenario.
When installed correctly, spray cork systems are typically backed by a 15-year warranty and designed for long service life.
Yes, particularly where breathability and moisture movement are important.
