Research on the Thermal Conductivity of Korean and US Cellulose Insulation

Abstract

Cellulose insulation was introduced into Korea in the 1980s when several small companies started production. The cellulose industry in Korea is still in an early stage of development with current production of about 1000 tons a year. The Korean equipment used to produce cellulose insulation was imported from the United States and installed by U.S. technicians. A typical cellulose manufacturing plant includes facilities for storing and moving large quantities of waste paper, chopping and shredding, milling or fiberizing, adding chemicals, and packaging. For broader use of cellulose insulation in buildings in Korea, it is necessary to establish its thermal performance. To this end, the effect of density and temperature on the thermal conductivity of loose-fill cellulose insulation manufactured in Korea and U.S. was reported. The apparent thermal conductivity of a particular type of spray-applied cellulose insulation was also determined and compared with previously published data. Apparent thermal conductivity (ka) measurements of Korean-made loose-fill cellulose insulations were completed using equipment that was built and operated in accordance with ASTM C 518. Korean loose-fill cellulose has thermal conductivity about 5% greater than the corresponding U.S. product at the same density. This is likely due to differences in the recycled material being used. Both spray-applied and loose-fill cellulose insulation lose about 1.5% of their thermal resistivity for 5.5°C increase in temperature.