NCC is building an attractive office building in Vallensbæk south of Copenhagen; Vallensbæk Company House. Here, we can offer the small business benefits of the large company. The low-energy building has a high level of insulation, energy efficient windows, and improved air tightness. Air tightness is a focus area when NCC builds.The building is heated with district heating combined with a ventilation system with heat recovery. The calculated energy consumption is 25% lower than required in the energy frame in the danish building code.