Long-term experience with Passive House buildings is illustrated with two early large-scale projects, a school and an office building located in Germany. Those were monitored in lump energy performance (school, commissioned 2004) and great detail (office, commissioned 2002), respectively. Moreover, they give an indication of the characteristics of such buildings subject to changes in usage intensity. Both buildings generally performed as expected with the school facing occasional overheating in the summer due to inflexible shading controls. Following an extension in schooling hours, the addition of a canteen was required and the ventilation system was adapted to the changed usage. Nevertheless, the building’s user comfort and energy performance remain high, despite exceeding the Passive House primary energy target slightly due to increased electricity consumption. The office likewise meets the calculated efficiency in operation. The ground-coupled cooling worked well despite greatly increased internal heat gains due to unexpected usage. This extra heat input did not, however, exhaust the geothermal (passive) cooling capacity for the future. Thermal comfort proved near optimal at all times, despite a very simple control regime of the one-circuit concrete core activation system for heating and cooling. In the last section, airtightness design and measurement experience in the UK and, particularly, the question of long-term stability of the airtight building envelope are assessed. It was found that measurement results are not only repeatable in relatively short intervals such as a few months. The data available suggests stability of the airtight envelope over many years. Attention is required as regards the leakage of party walls of terraced buildings which need to be integrated in the overall airtightness concept. A high permeability of party walls in terraced buildings with a common airtight envelope presents a challenge for measuring airtightness. Long-term series of airtightness measurements exist for the Kranichstein House in Darmstadt, Germany, and prove the stability of the chosen airtightness concept. Moreover, results for 17 early Passive House buildings in Germany in eight locations and various construction types revisited in 2001 (1.4 to 10 years after the initial airtightness test) suggest stability of airtightness values over time. Great advances have since been made in materials and methods available and the general understanding in the industry. This is supported by a large sample of 2934 Passive House projects of varied construction materials, locations, sizes, and usages that yielded an average airtightness test result as low as n₅₀ = 0.41 h⁻¹.

被动房屋建筑的长期经验通过两个早期的大型项目，一所学校和一栋位于德国的办公楼得以说明。分别以整体能源绩效（学校，2004年投入使用）和细节（办公室，2002年投入使用）进行监测。而且，它们指示了这种建筑物的使用强度变化的特征。由于不灵活的遮阳控制，两栋建筑物的表现通常都与预期一致，夏季学校有时会出现过热。在延长上课时间之后，需要增加一个食堂，并且通风系统适应了变化的用途。不过，建筑物的使用者舒适度和能源表现仍然很高，尽管由于用电量增加而略微超过了被动房的一次能源目标。办公室同样满足计算出的运营效率。尽管由于意外使用而大大增加了内部热量，但接地耦合的冷却效果很好。但是，这种额外的热量输入并没有耗尽未来的地热（被动）冷却能力。尽管用于加热和冷却的单回路混凝土芯激活系统的控制方式非常简单，但热舒适性始终都被证明接近最佳。在最后一部分中，评估了英国的气密性设计和测量经验，尤其是气密性建筑围护结构的长期稳定性问题。发现测量结果不仅可以在相对短的间隔（例如几个月）内重复。可用的数据表明气密性封套在许多年内都稳定。需要注意梯田建筑物的方墙泄漏，这些泄漏必须纳入整体气密性概念中。带有普通气密外壳的梯形建筑物中，宴会厅壁的高渗透性对测量气密性提出了挑战。德国达姆施塔特的克拉尼希施泰因故居对气密性进行了长期测量，证明了所选气密性概念的稳定性。此外，德国在八个位置的17座早期被动式房屋建筑的结果以及2001年重新审查的各种建筑类型（初始气密性测试后的1.4至10年）表明，气密性值会随着时间的推移而保持稳定。自那时以来，在可用的材料和方法以及业界的普遍理解方面已取得了巨大的进步。这是由大量2934年的被动房项目样本支持的，这些项目的建筑材料，位置，大小和用途各异，产生的平均气密性测试结果低至n ₅₀＝ 0.41h ^-1。