A measurement system for the long-term diagnostics of the thermal and technical properties of wooden houses

Jakub Svatos,Jan Holub,Tomas Pospisil

doi:10.21014/acta_imeko.v9i3.762

Abstract

To reduce construction costs and to increase energy savings and indoor environmental quality in a wooden house, an energy consumption measuring system for the diagnostics of the thermal and technical properties of building envelopes has been developed. At present, the vast majority of calculations for the thermal and technical characteristics of buildings are based on simple mathematical models of building envelope behavior, and these are derived primarily from the thermal transmission of individual materials. However, thermal transmission is measured in a stable laboratory environment. Therefore, the measured values may not match the real behavior of materials in continually changing climatic conditions. The energy consumption measuring system was installed in seven wooden houses in different climatic areas to diagnose the thermal and technical properties of a building envelope. The power consumption, temperature, and humidity of the air as well as of the wood; CO2 concentration; the temperature of the individual layers of the envelope sandwich structure; and wind speed and direction were measured. Thanks to the sets of real measurements of the measured thermal and technical behavior, the actual dependence of the indoor environment quality on the outdoor climatic conditions can be ascertained. The presented system can reveal imperfections in the heat capacity and hygroscopicity of materials used for the construction of a wooden house. Based on this measurement, the materials can be revised to save construction costs and energy; to increase the indoor environment quality; and to reduce the impact on the environment by decreasing the amount of used materials.

Highlights

This article presents a building energy consumption monitoring system for the determination of a heat transfer through the individual parts of a wooden house envelope for the diagnostics of the thermal and technical properties of buildings.The increasing demand for energy-efficient buildings – wooden houses – during the past decade has caused a higher standard of the thermal insulation of building envelopes
Due to the fact that only the surface temperature of the tested object is measured and the other quantities such us heat flux density or heat transfer coefficient are implicitly calculated, these results do not correspond to actual conditions
In cooperation with the construction company RD Rymarov s. r. o., seven different one- and two-storey residential wooden houses were selected for diagnosis for more than three years

Summary

Introduction

This article presents a building energy consumption monitoring system for the determination of a heat transfer through the individual parts of a wooden house envelope for the diagnostics of the thermal and technical properties of buildings. The increasing demand for energy-efficient buildings – wooden houses – during the past decade has caused a higher standard of the thermal insulation of building envelopes. There is no binding uniform methodology for the diagnostics of the wooden house sandwich structure system. These characteristics have been tested in the accredited laboratories in laboratory conditions, where real climatic changes are only simulated. The energy saving in such an over-dimensioned building is already negligible, and the hygienic comfort of a user is clearly deteriorating [2]-[4]

Methods

Results

Conclusion