Insulation and solar control in island servic buildings

The study of a hotel to be built under the mild climate of Madeira Island, Portugal, is presented. The program DOE-2.1E was used for the thermal load simulation, using as climatic input a Typical Year file constructed for this case. The simulation for the base building showed low heating loads and high cooling loads, of which a very important fraction derives from solar gains. Changes in the building envelope were then considered, and it was found that controlling solar gains by means of shading and adequate glazing can strongly reduce the cooling loads although slightly increasing the heating loads. On the other hand, the increase of the thermal insulation of walls is not advisable as it increases the cooling loads while the reduction on heating loads is of little importance. In
fact, the exterior walls help release the heat stored in the mass inertia construction during the day, especially from solar gains, and this effect is reduced when greater insulation is applied. As a result, care should be taken during the building conception or when making thermal regulations for buildings since using high thermal insulation of exterior surfaces is not a good practice for all types of climates.