"Holstenshuus" was built in the 1870s on Fyn, Denmark's third largest island. Over the years, the former barn became three rental apartments with a total of more than 500 square meters. In 2014, the time had come: renovation was inevitable, mainly because of the urgent need to insulate the interior walls of the three half-timbered houses. To ensure sufficient air circulation, an autoclaved aerated concrete (AAC) insulation solution with Multipor in combination with a layer of clay was installed.

But it wasn’t just a simple renovation: to monitor the AAC’s ability to repel moisture and keep the listed house in good condition, moisture meters were installed in several walls, and the first results are now in. "The moisture measurements are very good - and we will continue to monitor for many years to come," says Joakim Wandegren, Head of Technical and Sustainability at Xella Scandinavia. Insulation with Multipor reduces energy consumption and improves the indoor climate without disturbing the historic half-timbering of the former farmhouse. In addition, the material is vapor permeable, allowing moisture to penetrate naturally without trapping it and endangering the structure.

A useful tool in the walls

For four years, carpenter Morten Bro has been responsible for the extensive renovation of Holstenshuus, which he wanted to be as healthy in 100 years as it is today. To achieve this, Xella used these modern but unusual methods.

Moisture meters in the north and south walls, as well as in an interior wall, reliably show Morten Bro how the AAC transports moisture. "The measurements give us a good tool to see if Multipor is working with moisture as it should. We are very impressed with Multipor's ability to work with the clay to create a healthy indoor environment," says Morten Bro. "The AAC proved to be the right choice and ensured that the house was not 'over-insulated'. Otherwise, there would be a risk of not being able to remove the moisture. "The reason for the good values is that autoclaved aerated concrete is extremely breathable," explains the experienced carpenter.

Modern methods attract other craftsmen

It is no longer just the garden and the beautiful landscape around Holstenshuus that attract visitors: the solid and sustainable craftsmanship has also become a magnet for many craftsmen from outside who want to learn and see for themselves how Multipor can be used to ensure a healthy indoor climate in a half-timbered house: "They are impressed as soon as they walk through the door. They are greeted with a pleasant experience of temperature, humidity, and comfort," says Morten Bro. "It is something special to be involved in the renovation of a place like Holstenshuus. Our vision was that the renovation should last at least 100 years and be sustainable. That's why a product that consists only of lime, sand and water is perfect for this," says Morten Bro.