Determination of economical thermal insulation thickness for a building wall with two parallel structures

Journal of Building Physics

Zou

Memon

et al. 2019

Heat transfer through building opaque envelope is responsible for approximately half of the total heat loss and gain to and from the surroundings. Therefore, insulation materials are commonly used in the building envelope to reduce the heat transfer. Recently, lightweight wall materials with lower thermal conductivity are used in construction along with the commonly used materials such as heavy concrete and earthen materials. In this perspective, there is a need to understand the optimum insulation thickness for different types of building construction materials to minimize unnecessary usage of insulation materials. This study investigated the optimum insulation thickness for different construction materials following a life-cycle approach, where an analytical optimization methodology based on the degree-days method and life-cycle cost analysis was used. In total, 4 insulation materials and 15 building construction materials were considered in the optimization study. The objective function was to minimize life-cycle cost corresponding to the decision variables including insulation thickness and the thermal conductivity of insulation and wall materials. The results showed that the use of insulation in lightweight wall materials is not economically feasible because of their negligible cost-saving potential (below US$2.5/m2-year). However, the walls with heavy concrete and earthen materials that have high thermal mass must be insulated due to their highest cost-saving potential (US$14–26.39/m2-year).

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

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Life-cycle cost analysis of building wall and insulation materials

Journal of Building Physics

Zou

Memon

et al. 2019

“…The optimum insulation thickness corresponding to maximum cost savings of the building envelope (Açıkkalp & Kandemir 2019;Axaopoulos et al 2019;Orzechowski & Orzechowski 2018), pipes (İlhan 2018;Martin-Du Pan et al 2019;Ucar 2018;Yin et al 2018), and ducts (Kumar et al 2019;Kumar et al 2018a;Kumar et al 2018b;Kumar et al 2018c, Soponpongpipat et al 2010Yildiz & Ersöz 2016) was investigated by using LCC analysis. The present research also conducts the LCC analysis to determine the impact of an air gap on (Kumar et al 2019;Kumar et al 2018a;Kumar et al 2018b;Kumar et al 2018c;Soponpongpipat et al 2010;Yildiz & Ersöz 2016) considering the prevailing economic circumstances of a country (inflation and interest rate) on insulation investment and fuel billings (Huang et al 2019;Kumar et al 2019). In this analysis following assumption are made:…”

Section: Description Of Heating Ventilation and Airmentioning

confidence: 99%

Lifecycle cost analysis of an insulated duct with an air gap

Khan

Abro

2021

Environ Sci Pollut Res

The insulation materials are used to reduce heat loss to/from the ducts with additional investment. This study aims to reduce this additional investment in the duct application by introducing an air gap between insulation and duct surface. It uses Life Cycle Cost (LCC) analysis to determine the economic benefits of the air gap considering four insulation materials for insulating the duct and natural gas as an energy source for chiller operation. The preliminary data regarding design and operating parameters were obtained from a renowned pharmaceutical company. The duct's annual energy loss was estimated for given operation hours in a year using the preliminary data and ambient conditions. The estimated energy loss through the duct is fed in LCC analysis to determine the impact of the air gap on optimum insulation thickness corresponding to the minimum LCC and payback period. The results show that the introduced air gap in an insulated duct lowers the optimum insulation thickness for the duct. As a result, the air gap maximizes the cost savings and minimizes the payback period. The expanded polystyrene is investigated as the most economical with maximum cost savings of USD 508.8-USD $766.8/m/year and a payback period of 1.15-1.17 years for the duct applications. Contrary, the air gap is determined the most effective in terms of cost and emission savings for the ducts insulated with rock wool. In conclusion, an air gap is an economical option for duct applications.

“…The LCC analysis estimates the optimum insulation thickness corresponding to maximum cost savings of the building envelope (Açıkkalp & Kandemir 2019;Axaopoulos et al 2019;Orzechowski & Orzechowski 2018), pipes (İlhan 2018;Martin-Du Pan et al 2019;Ucar 2018;187 Yin et al 2018), and ducts (Kumar et al 2019;Kumar et al 2018a;Kumar et al 2018b;Kumar et al 2018c;Soponpongpipat et al 2010;Yildiz & Ersöz 2016) considering the prevailing economic circumstances of a country (inflation and interest rate) on insulation investment and fuel billings (Huang et al 2019;Kumar et al 2019). In this analysis following assumption are made:…”

Section: Life Cycle Cost Analysismentioning

confidence: 99%

Lifecycle Cost Analysis of An Insulated Duct With An Air Gap

Khan

Abro

2021

Preprint

The insulation materials are used to reduce heat loss to/from the ducts with additional investment. This study aims to reduce this additional investment in the duct application by introducing an air gap between insulation and duct surface. It uses Life Cycle Cost (LCC) analysis to determine the economic benefits of the air gap considering four insulation materials for insulating the duct and natural gas as an energy source for chiller operation. The preliminary data regarding design and operating parameters were obtained from a renowned pharmaceutical company. The duct's annual energy loss was estimated for given operation hours in a year using the preliminary data and ambient conditions. The estimated energy loss through the duct is fed in LCC analysis to determine the impact of the air gap on optimum insulation thickness corresponding to the minimum LCC and payback period. The results show that the introduced air gap in an insulated duct lowers the optimum insulation thickness for the duct. As a result, the air gap maximizes the cost savings and minimizes the payback period. The expanded polystyrene is investigated as the most economical with maximum cost savings of USD 508.8-USD $766.8/m/year and a payback period of 1.15–1.17 years for the duct applications. Contrary, the air gap is determined the most effective in terms of cost and emission savings for the ducts insulated with rock wool. In conclusion, an air gap is an economical option for duct applications.