Stochastische Berechnung bauleistungsspezifischer Risikokosten in der Angebotskalkulation

Abstract

Stochastic calculation of risk costs in construction projects during cost estimationThe amount of risk costs of construction projects depends on various project parameters, among others on the construction output. Therefore, in this study the amounts of risk costs of 26 risks are determined for three categories of construction output (< 200 000 €, 200 000-1 000 000 € and 1 000 000-2 500 000 € construction output). Only building construction projects with a construction output ≤ 2 500 000 € and unit price contracts applying the VOB/B are considered. By the use of a deterministic risk cost calculation it was shown that both, the amount of the risk costs and the order of priority of the risks vary, depending on the amount of the construction output. Furthermore, a stochastic risk cost calculation applying the Monte Carlo Method is used to reveal the range of risk costs depending on the construction output. Through the consideration of the average of the three categories it can be pointed out that the risk costs -without taking chances into accountrange between 2.71 and 8.67 % of the construction output. The results facilitate the contractor during the tender calculation to determine the amount of risk cost depending on the market situation, the company-specific risk disposition as well as strategic considerations.