Abstract: A high-performance door system is provided. The door system comprising a door leaf having a framework which includes first and second stiles spaced apart from each other, a first rail joining a first end of the first stile with a first end of the second stile, and a second rail joining a second end of the first stile with a second end of the second stile. The first rail is provided with a groove, and each one of the stiles comprises an inner channel, each inner channel being in fluid communication with the groove. The door leaf further comprises a housing defining a hollow space which is then injected with filler material so as to fill the hollow space and the groove, thereby spreading to each one of the inner channels, thus sealing interstices between the rail and stiles.