Impact of Temperature Drift on Thermal Sensation in nZEB Residential Buildings Under Winter Conditions

This paper is dedicated to investigating how short-term indoor temperature drift influences occupants’ thermal sensation in residential nZEB buildings and how this affects the applicability of steady-state comfort prediction. Residential buildings frequently operate under transient conditions, where the classical PMV approach may deviate from reported sensation. The objective of this paper is to evaluate the agreement between steady-state PMV and occupants’ thermal sensation votes under winter conditions to test a regression-based correction index Aeff and an adjusted indicator PMVadj while preserving the PMV concept. The study uses high-resolution measurements of indoor air temperature and mean radiant temperature synchronised with TSV responses, followed by statistical evaluation using error metrics and correlation analysis. The results show that baseline PMV correlates well with TSV but exhibits a consistent magnitude mismatch under transient conditions. The proposed PMVadj reduces this mismatch, decreasing NRMSE from 17.61% to 14.00% and slightly improving agreement with Pearson r = 82.18%, R2 = 67.54%. Regression analysis shows that Aeff is strongly associated with the indoor air temperature drift rate ΔTin/Δt with R2 = 0.6805, but has a weaker relationship with ΔTMRT/Δt, R2 = 0.1851. The research provides a practical basis for improving PMV-based comfort assessment during winter operation in residential nZEB.