Independent airtightness measurements conducted by Vertia Oy, an independent Finnish building testing and inspection company, confirm that Kontio log buildings achieve consistently excellent results. The latest verified results were published in March 2026, based on a comprehensive set of third‑party measurements carried out across completed buildings in Finland.

The results are internationally applicable, as the strong airtightness performance is based on repeatable log structures, joint details and construction principles that are consistently used in Kontio projects worldwide. These same technical solutions form the foundation of Kontio buildings regardless of location.

The results demonstrate that modern log construction can combine natural materials with high technical performance, delivering energy‑efficient and durable buildings across different markets and climates.