A growing focus on occupant comfort, health and wellbeing has resulted in attempts to quantify indoor environmental quality (IEQ) and to determine the relative contributions of single IEQ aspects to an overall IEQ index. The recently developed IV20 tool assesses potential IEQ to label overall IEQ, and assign separate scores for the main indoor environment (IE) areas: thermal, visual, acoustic and air quality. In the absence of objective, universally applicable IEQ weights, this paper develops and executes a methodology asking regional experts with different backgrounds to make relative comparisons between related IE aspects. The authors hypothesize that wide-ranging subjective evaluations can be combined into useful relative weights (best operational solution based on the current status of IE literature). This paper presents results from an IE expert survey on relative IE aspect weights using simple percentile prioritization and the Analytic Hierarchy Process pairwise comparison. Results are compared to expert panel judgements to ensure validity. The advantages of this combined weight determination method are (1) that the expert survey ensures a broad spectrum of opinions and allows for input from different built environment disciplines, and (2) that the expert panel has tool-specific insight, methodology awareness and state of the art knowledge.