Is Claypaint breathable?
25th January 2021
Many of our customers choose Earthborn because they have researched (or been advised to use) breathable paint.
Earthborn Claypaint is a highly breathable paint, perfect for walls and ceilings where breathability is key. It’s thick and creamy with a high clay content, offering excellent coverage, no nasty paint smells and a number of eco properties.
When we talk about paint breathability, we mean how much air and water vapour can easily flow through its surface. Older properties were built using materials that were designed to promote this airflow.
Using paint with a high level of breathability, coupled with breathable building materials, means that moisture doesn’t become ‘trapped’ beneath the surface of the paint. Lime for example, is a traditional building material which has been used in the construction of properties for hundreds of years, and shouldn’t be sealed with a plastic based paint. It’s durable yet highly flexible. Being moisture permeable, it allows the walls to breathe. So the paint used on top should be breathable too.
If you live in an older property, or have lime plastered walls, a breathable paint will help with this process. Using a non-breathable paint over lime plastered walls could cause problems with the fabric of the building if left. Trapped moisture can lead to damp walls, causing the paint to bubble, peel and eventually blow completely. It can also contribute to a harmful living environment. You can read more about tell-tale signs of damp (and how to tackle it) in this post.
The short answer is, Earthborn Claypaint is highly breathable! But to help explain, paint breathability can be measured in a couple of different ways:
The first is the Steam Diffusion (or SD) value, which is a German method for measuring breathability. It is widely accepted that for a paint to be classed as breathable it should have an SD value of 1 or lower; the lower the value the more breathable the paint.
Earthborn Claypaint has an SD value of just 0.02m.
The other method used to measure breathability is the moisture vapour transmission rate (MVTR). It measures the amount of water vapour (in grams) able to pass through the paint surface over a 24 hour period. The higher the figure, the more water vapour that can pass through, and therefore the more breathable the paint.
Earthborn Claypaint has an MTV of 1115g/m2/24h, compared with a typical emulsion paint which usually measures between 400-500g/m2/24h.
This is high level of breathability makes it perfect for lime plaster and an ideal alternative to lime wash, which can often be messy, time consuming and need reapplying every few years.
Coupled with its ease of use, high covering power and lack of harmful emissions, Claypaint is an ideal option for older properties, lime plaster and any home where breathability is a consideration. Click here to order a free colour card and find out more about our range.