With the globalization of green energy‐saving buildings, improving the thermal insulation performance of building exterior walls has become an important breakthrough in reducing building energy consumption. And the building envelope to improve insulation properties as a starting point for energy saving. Herein, a new type of material with excellent heat insulation and moisture resistance is developed. Hence, the sol–gel process, high‐pressure impregnation as well as supercritical drying are used to synthesize foam ceramic composite SiO2 aerogel (FC@SA) and foam glass composite SiO2 aerogel (FG@SA) materials. While maintaining the porous nanostructure of the aerogel, the aerogel is filled and embedded in the pores of the foamed material by a high‐pressure impregnation method. The thermal conductivity of FC@SA and FG@SA are, respectively, 0.04159 and 0.04424 W (m K)−1 at 25 °C, which are 36.02% and 23.72% lower than foam ceramic and foam glass. FC@SA reached water saturation (49%) in 48 h, while it took 72 h for FG@SA to reach water saturation (38%). Therefore, the composite building material prepared by embedding nano‐aerogel into ceramic foam and foam glass has great potential in the insulation material of building fence structures.

Thermal Insulation and Moisture Resistance of High‐Performance Silicon Aerogel Composite Foam Ceramic and Foam Glass

Solar application potential and thermal property optimization of a novel zero-carbon heating building

Novel approach to typical air-conditioning behavior pattern extraction based on large-scale VRF system online monitoring data

This study provides a reference for estimating the building envelope thermal performance at the initial stage of design for nearly zero-energy buildings in different climate zones. A simplified model of heat load prediction, which combines the quasi-steady-state thermal balance calculation procedure in ISO 52016 and the variable-base degree-days method, was proposed. Therefore, a building energy performance evaluation tool BPT V1.0 was developed. Subsequently, the simplified model was validated through comparative analysis with the Building Energy Simulation Test (BESTEST) standard procedure. To conduct a feasibility analysis of the development tool, case studies were performed on the performance evaluation of building envelopes of residential and office buildings in different climate zones in China. Compared to the simulation results from EnergyPlus, the deviation of heat load calculated by BPT V1.0 was within 10%, which further verifies the applicability of the tool under different climatic conditions. Annual heat load under different thermal performance building envelopes was calculated through BPT V1.0. The building energy efficiency improvement rates were found to range from 30 to 60% in nearly zero-energy buildings in different climate zones in China. The study results can provide a reference for energy managers and a basis for estimating the building energy efficiency performance with different envelope thermal properties in the region.

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Simplified Model of Heat Load Prediction and Its Application in Estimation of Building Envelope Thermal Performance

Thermal Performance Evaluation of A Novel Building Wall for Lightweight building Containing Phase Change Materials and Interlayer Ventilation: An Experimental Study

Innovative building materials are being used in building envelopes for reducing their heating and cooling needs. This paper aims to assess the thermal impact of using lightweight concrete in Lebanese building constructions by pouring an 8 cm thickness of lightweight concrete on the roof and the slab and replacing traditional hollow concrete block by lightweight concrete blocks. Thermal properties of two different samples were experimentally determined: the first one (558 kg/m3) used for the roof and the slab and the second one (1074 kg/m3) used for the walls. Then numerical simulations were carried out for a Lebanese traditional detached house using the characteristics of these two samples. The thermally improved Light Weight Concrete building (LWC) was compared to a traditional Lebanese house base case (BC) using a dynamic building energy simulation tool in the four different Lebanese climate zones: coastal, mid-mountain, mountain, and inland zones. The results highlight the effectiveness of integrating LWC to building envelopes by reducing energy consumption and improving thermal comfort in both winter and summer climate conditions and in the different Lebanese climatic zones. The paper demonstrates that the use of LWC in the vertical walls replacing the traditional hollow blocks can reduce the heating needs by up to 9% and by up to 13% for cooling needs. On the other hand, adding a LWC roof screed has a very high impact on cooling and heating energy consumption, which can reach up to 74% in cooling energy savings and up to 24% in heating energy savings.

Michel Nasrallah

Papers

Thermal performance of lightweight concrete applications in building envelopes in Lebanon