To reduce the cost of fuel and heat loss from pipe surfaces, insulation needs to cover pipes when high temperature fluids are transported through them. Mineral wool has not only low heat conductivity but also good thermal and flame resistant properties. It can be used in a wide range of applications. To improve the performance of thermal insulation, it can be used in a composite material in combination with other insulating materials. Aerogel is regarded as one of the most promising high performance thermal insulation materials today, but only limited commercial products are available thus far due to cost and reliability factors. In this study, aerogel is produced in mineral wool using an ambient pressure drying process. The purpose of this study is to investigate the thermal performance of mineral wool–aerogel composite to meet the requirements for industrial applications. The experimental results indicated that silica aerogel can be successfully produced in mineral wool using an ambient pressure drying process. The cost and production time of this proposed process can be significantly decreased. As aerogel is mixed with mineral wool, the measured thermal conductivity of mineral wool–aerogel composite can be reduced from 0.071 to 0.055 W/m·K.