Living walls are described as pre-vegetated panels attached to vertical surfaces, or stand independently on vertical structures. They have numerous economic, environmental and social benefits for cities and environment as well as benefits for the indoor of buildings. It is claimed that providing a cavity between greenery and wall surfaces by applying a distance between living walls and the wall surfaces of the buildings can improve the performance of living walls. The cavity protects the wall against foliage and preserves it from decay, moreover acts as insolation and reduces heat transfer. The aim of this study is to examine the thermal performance of different distances between a living wall and the wall surface of the building in hot and humid climate of Malaysia. The study is divided into two parts, a computer simulation and an experimental test. In the first part, DesignBuilder was used as software for simulation to find optimum distances, and a validation was done to show the qualification of the software. An experimental procedure was formed to measure cavity and indoor temperature by applying real plants. For experimental test two identical boxes were used as small-scale rooms. One of them has the coverage of living wall and another has no greenery and is used as base sample. Blue trumpet vines (Thunbergia grandiflora) were plants for living wall. The data were recorded over the course of two months from April to June, 2013. The results and analysis of the results shows that 30 cm distance between the living wall and wall surface has higher effectiveness on the cavity and indoor thermal condition. (C) 2017 Elsevier B.V. All rights reserved.