The global corona virus pandemic (COVID-19) has shown a range of internal and external factors affecting construction industries resulting in unprecedented delays for many public projects, disruptions, and uncertainty about construction projects. This situation made the construction industry tend to use more advanced techniques to reduce the negative effective factors. This paper seeks to provide a qualitative worldwide perspective on the lessons learned from the COVID-19 pandemic and its positive effects on construction projects in the future. Following a thorough assessment process and conversations with experts in the building sector, eighteen factors were determined. The survey was distributed to determine the degree of importance of each factor. The data were collected from 132 respondents through a questionnaire distributed to engineers, contractors, and consultants. The data were evaluated using the Relative Importance Index (RII) based on the relative percentage of importance to calculate weights, then applied in the MATLAB program's fuzzy logic to calculate the probability of impact ratio. Based on the findings, a quantitative analysis of the factors affecting the projects was carried out using the fuzzy model. Thus, the fuzzy model was developed to estimate the percentage of time reduction in the schedule resulting from COVID-19's effects on construction projects. This study removes the ambiguity about the negative impacts on projects through which the construction industry strategic plan can be developed to take measures that lead to the application of modern technologies to reduce conflicts by avoiding or reducing the negative effects in construction projects.