Any construction project, even one that is excellently planned and organized, is prone to the risk of unforeseen events and problems, which in effect can cause late completion of works. The paper presents the results of the research conducted among Polish and Slovakian building contractors. One attempt was to identify and assess the potential causes of delays in the construction works resulting from the provisions of the contract. The knowledge of these factors can help contractors to take protective measures, reducing the risk of delays during the implementation of construction works.

Construction projects, even exemplarily planned and organized, bear a risk of unforeseen events and problems which can result in completion of the works after the deadline, that is delays. The construction of bridges is an inseparable part of road and rail projects and construction and expansion of the transport network. The paper aims at finding a relationship between the independent variables characterizing bridge projects and the delays during their implementation. Two alternative models were proposed to solve the problem: logit and probit. The data set comprising road and rail bridges built in Poland in the last 12 years (2005 – 2017) was used to build the models. The evaluation, quality and accuracy parameters of proposed models were determined in the final part of the paper.