Considerations on building skin for energy efficient design

All habitable spaces must provide the visual andthermal comfort, in order to give the inhabitantsa living in a pleasant environment (Naturallighting, heating and cooling). This can beachieved through thermal protection during winterand through the use of suitable techniquesapplied in the exterior shell of the buildings, inorder to establish the needed insulation and airproofduring summer.The role of the exterior shell is very important,because it protects the building against unpleasantweather conditions, like strong winds,humidity, and extreme solar radiation. Thesephenomena cause unfavourable conditions ofexistence. The shell is also important for the energyoutput. When considering a two-storeyhouse, the needs are more demanding than thosefor a one storey house. All floors should havethe conditions to offer a pleasant environment,in terms of thermal comfort and of day lightinglevels throughout year.In a project that took place in Patras, in theregion of Kastritsi, in a coastal plot, several bioclimaticprinciples were applied in a two-storeyresidence, in order to ensure its proper functionality.Due to the fact the building has smallopenings and therefore the exterior walls areexposed to winds, small temperatures duringwinter, and high temperatures during summer itstotal insulation and protection is required (Heatinsulation, airproof and sun protection). As itwas mentioned before the openings are relativelysmall. However it is recommended inseveral occasions their decrease in size mainlyon the Eastern and Western faades. This aimsin the reduction of heat gains during summer. Itis also recommended for the North faade, inorder to control the thermal losses during winter.Considering that a residence has increaseddemands due to its function special attentionshould be given to the selection of materials.