In recent years, wooden structures have been being gradually replaced by reinforced concrete and brick buildings. Although a conservation system has been established in Indonesia, specific conservation and repair guidelines for traditional wooden buildings have not been well-regulated. This paper takes the omo sebua as a research subject, aims to clarify the deterioration, deformation and their causes, and to propose guidelines for its conservation.

The results of the deterioration and deformation investigation are as following: the maximum inclination of the short pillars is 5/100, and the most common inclination is 2/100. The significant sinkage of the foundation stones reaches 56 cm and the average sinkage is 20~30 cm. The maximum inclination of side pillars is 4/100, and the most common inclination is 2/100. Besides, the corruptions of the roof frame concentrate on the gable wall and termite damages can be seen in the whole building.

Basing on the investigation result, our proposals are as following: 1) conduct a dismantling restoration; 2) recycle the used materials as much as possible to maintain the authenticity of the building; 3) use new materials that are the same as the original ones; 4) rethatch the roofing by sago palm leaf; 5) conduct a structural diagnose, reinforce the structure against an earthquake; 6) include electrical equipment and disaster management in a restoration.