By Vicki Sussens
Extracted from limestone found in abundance in Croatia, lime is the world’s oldest and most efficient building material. The firm Kapitel in Istria produces lime for historical preservationists in a kiln built to ancient specifications.
Branko Orbanić is passionate about his work: he is an architect specialised in historical preservation, and in 2000, built a lime kiln to revive an ancient method of producing the most important building material for restoring old buildings – lime.
The first law of conservation is to use traditional building materials and lime has been used as a binder for thousands of years. It also happens to be right on trend: it is sustainable, ecological and keeps buildings energy efficient. Orbanić explains how lime plaster absorbs excess moisture in a room, and releases it back when the room becomes dry. “This is a natural cycle that keeps humidity at ideal levels for people and furniture.”
Lime was used not only for mortars, but also to disinfect, keep stables hygienic, repel pests on fruit trees and to kill bacteria in well water. “It sounds like an all-round medicine,” I say. “Bravo!” answers Orbanić.
He proudly shows me the kiln, set in an idyllic stretch of Istrian countryside not far from Zminj, where he and his wife Gracijela, run the architectural firm Kapitel.
The kiln is partially buried in an embankment. The chimney is a simple hole in the ground. Outside, under the trees are wooden benches for the lime workshops held in summer.
We walk to a beautifully restored stone hut next to the kiln, the walls of which are covered in sample antique techniques: fresco (pigment applied to wet plaster) secco (pigment on dry plaster) and stucco (decorative relief). “Touch them”, he says, as I admire this whiff of ancient Venice.
The setting is so archaic that it is hard to imagine that this humble kiln has any kind of production capacity. Can such a small structure meet demand? Easily, says Orbanić. Kapitel is the only firm in Croatia supplying traditionally made lime, and works closely with the many historical preservationists now restoring Croatia’s long neglected architectural legacy – one that reaches back into prehistorical times. Kapitel also uses the lime in its own restoration projects, which include churches, monuments and traditional stone homes.
Orbanić was inspired to revive traditional lime production by a leading Austrian restoration expert, Hannes Weissenbach. “But I also remembered that in my own village there was an old lime kiln and a pit where the lime was slaked. Every village had this,” he says. “But the knowledge is fast disappearing.”
Limestone is found in abundance throughout Croatia. And Istria has a particularly good quality limestone, rich in the minerals needed to produce an enduring binder. The kiln gets fired up once in summer when the days are long, burning day and night for seven days. For quality purposes, the fire must be very clean and only thin branches of wood are used. Orbanić plays his part in ensuring quality by spending every night from 6 pm to midnight feeding wood into the fire.
To make the lime, limestone is burned. The firing produces the raw material called “quicklime”, which can be worked as is, or “slaked” in a “lime pit” of water to create “slaked lime”. This is then mixed with aggregates such as sand and volcanic ash to create various types of plaster. It can also be mixed with mineral pigments (which Kapitel also produces) to colour and decorate walls.
In summer, Orbanić holds workshops at the kiln. “My philosophy is that if you have valuable knowledge, you must spread it,” he says. He teaches about different lime applications, as well as ancient techniques to colour and decorate walls.
Ironically, while Croatia lags well behind Italy, Spain, Germany or Austria in the restoration of historical buildings, the Kapitel kiln is one of the only traditional lime kilns in Europe. “My foreign course participants cannot believe that in the 21st century, this very basic production of lime is taking place. In their own countries, lime production has been industrialized,” says Orbanić.
How it makes my heart sing to stand in this woodland factory, which sustainably and effortlessly produces a far superior plaster than the hypermarkets that have begun to colonise the building market in Croatia.
Orbanić says one reason he is promoting the use of lime is just because of this “turbo development” of building materials. “Consumers are flooded with ads for “ever better” materials, and in the hype around the “new”, builders are under pressure to use these products. But what about the old buildings in Croatia that were built using lime and are still standing after 2000 years!”
His workshops have had some influence in the industry, he says. But it’s not an easy battle. While strict laws mean original materials must be used in restoration projects, traditional stone homes are neither valued in Croatia, nor do they enjoy sufficient protection as a cultural good. The result is huge swathes of this legacy are being lost as houses are “modernized” and ancient villages lose their patina.
Orbanić clutches his arms in a physical display of despair. “This really gets me,” he says. He tells a story he often uses in his workshops. An Austrian had bought a beautiful old stone house full of charm. “The plaster, patched over centuries with different coloured soils, had a wonderful patina of grey, green and red shades. The roof had ancient terracotta tiles. Did you know that each tile was shaped on someone’s thighs? And the house had the typical perfect proportions of a classical home. Not a door or window was too large or too small, an arch too deep or too shallow.”
After the restoration, all the crooked lines had been straightened under a straightjacket of cement. The old stone window- and doorframes were replaced with new ones, the roof had modern tiles, and the house was painted orange. “People love this kind of house now because they think there is no alternative to renovating old buildings. But if you explain what a treasure they would have if they did a proper renovation, then things would be different,” he says. “That is why I teach.”
About the author
Vicki Sussens is a South African born journalist – now a German citizen, who divides her time between Germany and Croatia, where her family has a holiday home. https://www.clippings.me/sussens