###### Abstract  
Office buildings are usually characterized by low thermal inertia, which could cause underperformance in terms of energy consumption. Moreover, the use of large glazed facades in office buildings can cause thermal and visual discomfort due to high solar heat gains and excessive daylight transmitted into the office space. Phase Change Materials (PCMs) integrated into glazing have arisen as an innovative strategy to increase thermal inertia and improve office buildings' energy performance and indoor comfort at a low cost. This paper aims to analyze the impact of PCM glazing on buildings' energy performance and occupants' thermal and visual comfort. The analysis is performed through a one-year real-scale experiment in two offices in Santiago, Chile, with an east-oriented facade and a window-to-wall ratio (WWR) of 56%. The results are analyzed on two timescales: seasonally and daily. Representative days in each season were selected to carry out the analysis. Regarding the energy consumption of the HVAC system, PCM glazing reduces energy consumption during summer and mid-seasons and significantly reduces the peak loads in summer. A meaningful improvement in thermal comfort is achieved due to the control of the mean radiant temperature for the whole year. Considering visual comfort, there is an improvement in the luminance distribution in winter and mid-season cold conditions. P 2021 11 959  
facades. Additionally, glazing facades are characterized by lower thermal inertia. Moreover, office buildings with large glazing facades are affected by excessive solar heat gains and daylight that might cause high cooling energy consumption and thermal and visual discomfort. Therefore, it is necessary to develop new advances in glazing technologies to improve the thermal performance of the glazed facade of office buildings [4]. There are several advanced glazing technologies, such as multilayer glazing, suspended films, vacuum glazing, Low-E coatings, smart glazing, photovoltaic glazing, aerogel glazing, gas-filled glazing, self-cleaning glazing, and Phase Change Materials (PCMs) glazing [5]. PCMs integrated into glazing have emerged as an innovative strategy to provide thermal inertia to the envelope, improve office energy performance, and cost-effectively improve indoor comfort. The main benefit of PCM glazing is enabling the selective optical transmittance of solar radiation so that visible range radiation is mainly transmitted. In contrast, infrared radiation is absorbed and converted to heat, causing the PCM phase change [5]. Consequently, PCM glazing improves thermal comfort and produces a delay between outdoor and indoor conditions [6]. The literature review of [PERSON], et al. [7] shows that PCM glazing's main benefit is in warm-dominated climates to reduce overheating and significantly reduce cooling energy consumption. Several experimental studies on PCM glazing have been carried out in recent years. Researchers have focused on the characterization of PCM glazing, determining its impact on thermal and solar performance. The characterization of PCM glazing has been centered on determining solar properties, refractive index, and light transmission. For example, [PERSON], et al. [8] experimentally determined the spectral and angular solar properties of a double-glazed window filled with PCM paraffin for different cavity thicknesses. In addition, they provided properties to perform numerical thermal and lighting simulations of buildings with PCM glazing. [PERSON], et al. [9] studied the impact of the refractive index and extinction coefficients for a glazed roof filled with PCM in liquid and solid states. [PERSON], et al. [10] determined the direct light transmittance of a triple glazed unit with one cavity filled with PCM under constant solar radiation intensity and stable air temperature. They found that the interreflections inside the PCM glazing during the phase change cause nonuniformity in the light transmission.