Building envelope thermal performance testing dataset (Co-heating, QUB, ISO-9869 U-values) from a retrofitted heritage building (unoccupied dwelling)

A mobile Monitoring and Control System (MCS) was implemented to conduct several tests aimed at characterizing the thermal envelope of unoccupied dwellings and estimating its Heat Transfer Coefficient (HTC). These tests included U-value Tests (according to ISO 9869), QUB Tests, and Co-Heating Tests. In the Co-Heating Test, the dwelling was heated during different periods using both electric heaters and the installed aerothermal heat pump system. The two studied dwellings are living labs of a heritage building in Vitoria-Gasteiz (Spain), retrofitted in 2019 as part of the European project ENERPAT-SUDOE: <i>Experimentation in the Eco-Renovation of Old Built Heritage</i>. Specific ISO 9869 U-value or Thermal Transmittance Tests were conducted on the building envelope using 37 sensors strategically installed across two dwellings. In an unoccupied dwelling, the QUB Tests and Co-Heating Tests, were also performed. In total, the dataset includes 138 sensors measuring 200 physical variables to perform the test in different periods from October 26, 2019, at 15:53:00 to November 05, 2024, at 23:59:00 at 1-minute resolution.This dataset contributes to advancing the estimation of the Heat Transfer Coefficient (HTC) and the overall heat loss (UA-value) of the thermal envelope in retrofitted buildings, supporting improved energy performance evaluation. Companion dataset: multi-year in-use monitoring from the same building using a fixed MCS (Data in Brief DOI: 10.1016/j.dib.2025.112121).