A case study on thermal insulation as a comfort factor in warm humid weather housing

This research is developed within the framework of the environmental conditioning of houses in warm-humid climate and the obtaining of optimal thermal comfort conditions by passive means. The study of the thermal insulation of the dwelling is considered as an influencing factor in the achievement of the best habitability levels. The study focuses on a representative typology of dwelling in Havana (Cuba). Its geographical location makes this city one of the reference locations for the warm-humid climate. [1, 2, 3]. The effects and the influence of the additional insulation to the enclosure are analysed here. In order to achieve the targets proposed, the hourly evolution of the indoor air temperature under different environmental situations has been analysed using the dynamic simulation software: Transient Energy System Simulation Tool (TRNSYS 16.1). This is a modular and flexible software, that allows complex systems to be designed and the input variables and the contour conditions to be modified at each step time. Early results give a slight hint of the thermal behaviour of the dwelling under perimeter insulation conditions. In fact, these results justify a priori the quite widespread perception in the bibliography consulted, of the irrelevance in the use of insulation (if not of its inconvenience). Then, it seems pertinent to make a new study on the thermal conditions throughout the 24 hours of a specific day, in the case of the implementation of insulation in the external enclosures. The 17th of January was selected as a representative day in winter conditions, and the 23rd of July as a representative of summer. Both das are characterized by the regular oscillation of the external temperature in them [4, 5]. Among the main conclusions of the research carried out can be highlighted: - When the perimeter insulation of the external enclosures is considered, the maximum temperatures are up to 6ºC below the maximum external temperature. As the damping of the internal thermal wave is high and the amplitudes are very low, there is a very important stability of the internal temperature of the dwelling when this insulation is implemented. - From the analysis carried out it can be deduced that the typical thickness of the insulation is 4 cm, in correspondence with the specifications of the Cuban Standard NC 220-1: 2009 for the insulation of roofs. - The perimeter insulation together with a possible shading of the openings provides in winter an indoor temperature almost constant throughout the 24 hours of the day at around 22ºC. Which represents a clear improvement compared to the absence of insulation. In such a case a normal ventilation level is enough. - In the summer, with perimeter insulation and possible shading of the openings, the minimum indoor temperature is only 2ºC higher than the minimum outdoor temperature. This provides an average indoor temperature close to 26ºC, in a clearly a comfortable situation. In this case, a medium-high ventilation level is preferable, although not crucial. - As a main conclusion it can be stated that a solution with the implementation of 4 cm of perimeter insulation combined with solar protection of the external hollows confers the dwelling a very good level of comfort to the warm-humid climate, both in winter and in summer. Being not necessary but appropriate an additional level of ventilation