Sammendrag
Natural disasters caused by extreme weather events are obvious challenges to the built environment. However, variations over normal everyday impact from different climate parameters, and increasing demands in the construction industry for profit and shorter construction periods, also prove to be a significant challenge. The Norwegian Building Research Institute (NBI) has undertaken analyses of building defects for more than 50 years, both on behalf of the construction industry and in comprehensive field investigations. This considerable source of experience-based knowledge is now for the first time being thoroughly analysed. It is found that NBI has more than 5,000 process induced building defect assignment reports in its archives. This paper presents preliminary results from a review of assignments investigated in the 10-year period 1993-2002 (2378 building defect cases registered and described in 2045 assignment reports). Defects related to the building enclosure constitute about two thirds of the investigated cases. Moisture as the main source causing the defect replies for as much as 76% of all investigated cases in the 10-year period. Many types of building defect cases are recurring items, which indicate a general lack of knowledge amongst the different actors in the construction industry concerning fundamental principles of building physics.
It is significant to emphasise that only a small part of the total amount of process induced building defects in Norway emerges in the building defects archive. However, the archive contains a large amount of assignments over a long time period, with thorough descriptions of cause, extent and preventive actions on complex building defect cases, investigated and described by highly competent researchers. Despite the archives shortcomings in terms of general validity, it must be regarded as an important source of knowledge that allows for in-depth analyses of causal relations of different types of building defects on a wide variety of building enclosure elements.
It is significant to emphasise that only a small part of the total amount of process induced building defects in Norway emerges in the building defects archive. However, the archive contains a large amount of assignments over a long time period, with thorough descriptions of cause, extent and preventive actions on complex building defect cases, investigated and described by highly competent researchers. Despite the archives shortcomings in terms of general validity, it must be regarded as an important source of knowledge that allows for in-depth analyses of causal relations of different types of building defects on a wide variety of building enclosure elements.