Assessment of envelope’s thermal performance by different MCDA techniques

Abstract

The assessment of the thermal performance of multilayered envelopes was performed by different techniques of MultiCriteria Decision Analysis (MCDA). There was a proposed integral index of thermal performance as a comprehensive evaluation parameter. As key influence criteria were taken into consideration as follows: the u-value of the envelope W/m2K, the dimensionless decrement factor of the envelope f, the internal areal heat capacity of the envelope k1, kJ/m2K according to ISO 13786:2017, the cost of the wall material, UAH/m2 and the mass of the wall kg/m2 . There were compared eight types of wall assemblies from natural materials: hempcrete, adobe, strawbale panel, earthbag, cordwood, SIP, hempcrete+straw and compositional building thermo-block. The comparison of the alternatives was proceeded by such MCDA techniques as AHP, TOPSIS, Grey relation analysis (GRA) and Criteria Importance Theory (CIT). Conducted research revealed that only two of eight wall types could be approximately defined as “medium” and “best” ones in proposed terms of thermal performance – Wall from SIP and Wall from Cordwood. respectively.