The Hotel MiM Sitges was constructed in a building that is both sustainable and environmentally-friendly. Not in vain was 80% of the material used for the building's construction recycled or recyclable, while omitting the use of PVC, polymers, or petroleum products as well. The façade is made almost entirely of glass covered with seven layers of high-thermal capacity plates, a material which maintains the temperature without wasting more energy and also prevents noise pollution. In addition, all of the hotel windows have a high light factor so that ultraviolet rays cannot enter while obtaining the same degree of natural light and without darkening the glass. Regarding the efficient use of water, showers throughout the building have a system which, by taking in air and water at the same time, consumes less water (a maximum of nine litres per minute) while giving the guest the same sensation of comfort. The hotel also has tanks that collect the waste water from every shower which is then filtered, cleaned, treated, and used in the toilets and for watering all of the plants. In terms of energy, the hotel has lowconsumption LED lights, solar panels on the terrace that heat the water for all of the showers in the hotel as well as the spa, and windmills - also on the terrace - that generate enough energy to illuminate all of the common areas of the hotel. The hotel's ventilation system, apart from supplying air conditioning or heating using a VRV (variable refrigerant volume) system, also purifies the air. This system neutralises polluting emissions such as pollen and other allergens. Additionally, the Hotel MiM Sitges has bicycle parking available for employees. In the parking area are two charging stations for electric vehicles as well as two designed specifically for Tesla vehicles. All of these measures have earned the hotel the LEED certification (acronym for Leadership in Energy and Environmental Design). This is a certification system for sustainable buildings developed by the US Green Building Council. Initially implemented in 1993, there are currently more than 30 countries with certified buildings. Among these is the Hotel MiM Sitges, which, four years ago, was the first hotel in Europe to receive the certification, in addition to its highest level, Leed Platinum.