Every Dores house undergoes a blower door test - not because it looks good in a brochure, but because airtightness is measurable, and what is measurable is accountable.

Why does airtightness matter? High airtightness ensures lower heating demand, stable indoor temperatures, no uncontrolled drafts, protection of structural elements, controlled ventilation through mechanical systems, and long-term durability of the building envelope. In cold climates - especially in Northern Europe - airtightness directly affects both comfort and energy efficiency.

Here is a brief explanation of how a blower door test works. A calibrated fan is installed in an exterior doorway. The house is then pressurized and depressurized to 50 Pascals, and the system calculates how much air leaks through the building envelope. The result is expressed as n50 - the number of air changes per hour at a 50 Pa pressure difference. The lower the number, the better the airtightness.

One of the strictest airtightness benchmarks in the world is set by the Passive House Institute. For passive houses, the requirement is n50 ≤ 0.6 air changes per hour. This means that under test pressure, the entire volume of air inside the house may be replaced by uncontrolled leakage no more than 0.6 times per hour. For many builders - especially in log construction - this target is considered extremely ambitious.

Log houses are often associated with tradition, natural materials, and visible structural elements. They are rarely associated with ultra-high airtightness. And yet, when quality, precision, and professionalism come together, the results speak for themselves. In a recent Dores log house project, the achieved airtightness was three times better than the passive house requirement - n50 ≤ 0.18! Achieving such performance is only possible through exceptional detailing at every joint, precise log profiling and assembly, careful sealing of connections and service penetrations and on-site execution that leaves no room for compromise. This is not an accidental - it is engineering discipline combined with craftsmanship.

Blower door testing is not an optional extra – we test each and every Dores house as part of our production process. Because quality should never rely on assumptions - it should be verified. And when verification demonstrates results that outperform one of the strictest standards in the world, it confirms what we believe: log construction and energy efficiency are not opposites. Log house can achieve modern energy performance levels. Our regular blower door test results prove that solid timber, when properly engineered and precisely assembled, is an outstanding building material. Combined with modern detailing and quality control, log construction can meet - and exceed - the highest energy efficiency standards.