Limepinnoitteita

Limepinnoitteita, often translated as lime coatings or lime renders, are traditional building materials made primarily from slaked lime, sand, and water. These finishes have been used for centuries across various cultures due to their durability, breathability, and aesthetic qualities.

The fundamental component is lime, specifically calcium hydroxide, which is produced by slaking quicklime (calcium oxide) with water. This process, when done correctly, results in a paste that, when applied to a surface, reacts with carbon dioxide in the air to reabsorb the CO2 and harden back into calcium carbonate, a process known as carbonation. This slow, natural curing process is key to the performance of lime-based finishes.

Lime coatings are highly permeable, meaning they allow water vapor to pass through them. This "breathability" is crucial for maintaining healthy building envelopes, as it prevents moisture from becoming trapped within walls, which can lead to rot and other structural issues. This characteristic makes them particularly well-suited for historic buildings and structures made from permeable materials like stone or brick.

Aesthetically, lime finishes offer a soft, matte appearance with a unique depth of color. They can be applied in various textures, from smooth plasters to rougher renders, and can be pigmented to achieve a wide range of natural hues. Their ability to age gracefully, developing a patina over time, is another reason for their enduring appeal in contemporary architecture as well as historical restoration projects.