Comfort in buildings is one of the most requested value to reach. Today, designers have to deal with so many technical features including outer appearance, air-conditioning, structural layouts, acoustic insulation and inner treatments, materials bio-compatibility, material recycling and reuse, water wasting and so on. In the same time, costumers want to buy buildings which won’t cost a lot in terms of heating and cooling as in the past. Besides, every single apartment, loft, office etc., even if there are many of them in a single building, has to be very quiet. Voluntary or compulsory standards, protocols and state laws lead the designers throughout the project and in some cases to the final in field tests too. Nevertheless, different sort of calculations, leading philosophy, expected results, parameters and tags are included in order to achieve the final aims. In this paper, energy efficiency and acoustic performances of buildings are discussed, proposing and comparing designing solutions for a specific case study.