Lime as an anti-bacterial coating

Lime as an anti-bacterial coating

The mineral and chemical composition of limestone

We spend up to 90% of our time indoors so the quality of the internal environment is important to our health and wellbeing. A breathable building is a healthy building.

Limestone is a naturally occurring anti-bacterial material that comes in several types. These include calcite and dolomite. The term limestone can refer to any sedimentary rock that contains abundant amounts of calcium carbonate (CaCO3), including marble and chalk.

“Calcium carbonate is a chemical compound with the formula CaCO₃. It is a common substance found in rocks as the minerals calcite and aragonite”

Interestingly, this compound is the main component of eggshells, shellfish skeletons and pearls.

Limestone is an extremely versatile building material. It has been used for thousands of years, and its many applications include the production of cement and lime. But did you know that limestone also has anti-bacterial properties?

Lime used as an anti-bacterial coating

Lime is commonly used for home interiors as it has many benefits as a material.

Firstly, lime plaster is hygroscopic. This literally means ‘water seeking’ as it draws the moisture from the internal to the external environment. This is beneficial as it helps to control condensation and mould growth in the building.

Lime has natural antibacterial properties which make it ideal for use in kitchens or bathrooms. Apart from being a popular, natural way to cleanse your home. It will rid your home of bacteria and mildew whilst freshening the air naturally.

The ideal humidity level of a building is between 40-60%. If it is drier than this, or more humid than this, harmful agents are able to live and thrive.

Lime itself has antibacterial properties that help reduce the spread of germs. Made up of calcium carbonate and due to limestone being alkaline, it has natural anti-bacterial properties. It is often used in agricultural buildings or to disinfect cellars by killing mould. This compound has been found to be an effective anti-bacterial agent, which is why it’s used in so many medical applications.

Also, limewash is mildly antiseptic as well as anti-bacterial. Therefore, limewash is regularly applied to agricultural buildings. Because of these properties, many farmers still do this prior to lambing to ‘cleanse’ the environment.

Did you know that lime was used during the Great Plague in London? It was ordered by Charles II that all residential dwellings have lime-based plaster to kill harmful bacteria.


The antibacterial properties of limes are an important part of our lives, and we should appreciate them. Whether you have it in your home or not, it is good to know that there are natural ways to keep your surroundings clean and fresh for everyone to enjoy.

  1. Lime is an excellent anti-bacterial material.
  2. Lime is breathable.
  3. Lime is hygroscopic.
  4. Lime can also be found in toothpaste and other personal care products because of its natural antibacterial properties
  5. Lime has many natural antibacterial substances, which are commercially available.
  6. Used by farmers to cleanse the environment prior to lambing

Lime also has a fire rating class of A1. A1 materials are completely non-combustible and therefore limestone is often used to create fire retardant structures.

Further information on how you can use limestone as a fire-retardant building material can be found here:

About Ecoright

Ecoright have been working with architects, housebuilders and specialist brickwork contractors for many years, so their knowledge of lime and its uses is extensive. If you have any questions about how to use lime or its suitability to a particular project, please get in touch, they will be pleased to advise. You can read more about Lime Renders here:

Lime Renders are available through Ecoright’s sister companies:

Lime Render – the natural choice for exterior and interior work Lime Render – the natural choice for exterior and interior work

Lime mortar is highly aesthetic and can be exact colour-matched to bricks or other adjacent materials making it a good choice for conservation or new build.