The article presents the results of the research on the state of conservation of the roof of the Church of the Holy Governors in Ceplenița, which was built in 1802 by the logofat Iordache Cantacuzino-Pascanu and in 1939 was declared a historical monument. Under proper conditions, wood will provide centuries of utilization, however, under conditions that allow the development of wood-degrading organisms, protection must be provided during processing, marketing and use. Organisms that can degrade wood are mainly fungi, insects, bacteria. Molds, most sapwood stains and decay are caused by fungi, which are microscopic microorganisms that must have organic material to live. For some of them, wood provides the necessary food supply. Fungal growth depends on proper temperatures, humidity and air (oxygen). Insects also damage wood and, in many situations, must be taken into account in protective measures. Bacteria in wood are usually of little importance, but some can make wood excessively absorbent. The degradation of wood by organisms has been extensively studied, and many preventive measures are well known and widely practiced. By taking the usual precautions with the finished product, the user can contribute substantially to ensuring a long life.