ADOBE BRICKS TO HOLLOW SANDCRETE BLOCK WALLING IN TROPICAL BUILDING CONSTRUCTION: MATERIAL IMPACT ON SUSTAINABLE INDOOR THERMAL COMFORT ATTAINMENT

Abstract

Introduction: Tropical climate is characterized by high temperature, the consequence of which induces indoor thermal discomfort. This is attributed to high solar gains through various elements of the building envelope, including windows, walls, and roof among others. However, in an attempt to optimize indoor thermal comfort with minimal or no recourse to mechanical installations, this study explores the roles of the walling fabrics by comparing varying thermo-physical properties of two identified masonry units in the study area of Ogbomoso, Nigeria (adobe bricks and hollow sandcrete blocks), with a view to identifying a more thermally comfortable and sustainable material option. The methodology involves virtual models of two similar residential buildings each composed of either adobe bricks or sandcrete blocks, as masonry units. These models were subjected to energy performance simulation analyses using DesignBuilder software, over a 12‑month cycle period, to experience year-round differential thermal conditions. Through the observed comparative annual heat loads as experienced in the models, the results show improved indoor thermal comfort in the brick building (i.e., 7119.54 KWh), with heat loads being 11% lower than that of the sandcrete building (i.e., 8875.65 KWh) due to the brick walling fabric. This may be associated with the brick’s lower thermal conductivity (U-Value) of 1.798 W/m2-K, compared with the sandcrete blocks’ value of 1.999 W/m2-K. Results: In general, adobe bricks as a walling unit exhibit more thermal resistance against the harsh outdoor weather conditions than sandcrete blocks. The study is part of an ongoing effort towards reviving this partially neglected low impact material — adobe brick — with a view to attaining sustainable indoor thermal comfort as well as protect the environment in the study area.