Gudul is a traditional heating system which was created by our ancestors. This study is focused to the developments of new flooring material through the physical and chemical analyses of the Gudul rocks. The study proceeded with selecting the theme and study areas, sampling, geological survey, several analyses of the rocks, development of new floor material (a kind of porcelain). Gudul rocks are sampled from a total of twenty one cities and counties are assigned to nine tuffs, five quartz porphyries, four gneisses and three schists in rock type. From the geological study, these rocks are very similar to ones in surrounding areas. Comparing Gudul rocks to others not used in Ondol, Gudul rocks show low densities, higher porosities and brittle features. Analyzed in thermal properties, the rocks are lower in conductivity but higher in conservation and resistance in the aspects of the properties. Considering mutual relations between thermal properties and chemistries of the rocks, conservative characteristics are proportional to MgO contents but not to SiO2. In particular, minute quartz grains in the rocks were gradually cracked and rejected under torch flames. Those features may indicate that quartz grains are closely related with the thermal resistances of the rocks. On the basis of above rock characteristics, new flooring material was made. The material includes the mixed states of amphibolite sludges with high MgO contents and white china soils (bearing kaolinte). Then, the material was tested in the above thermal properties under the variable mixed ratios. At the results, 4:6 (sludge : soil) ratio was the most excellent among above tested materials. So, the textiles used in architecture and the electric heating cushion and the mugcups were produced as test goods.

Abatract
 1. Introduction
 2. Methods
  2.1Collecting information on Guduljang
  2.2 Geological characteristics of Guduljang
  2.3 Physical characteristics of Guduljang
  2.4 Chemical characteristics of Guduljang
  2.5 Thermal characteristic of Guduljang
 3. Results
  3.1 Geological characteristic of Guduljang
  3.2 Physical characteristics of Guduljang
  3.3 Chemical characteristics of Guduljang
  3.4 Thermal features of Guduljang
  3.5 The relation between Guduljang's thermal characteristics and chemical composition
  3.6 Minerals affecting thermal resistance
  3.7 Living goods adapted by the thermal characteristics of Guduljang
 4. Conclusion
 Reference

• Subin Sin(Damyang High School)
• Hyuna Choi(Damyang High School)
• Songcheol Kim(Damyang High School)