Multiple Subcontractors Working in One Room vs. Reality

Have you ever encountered the problem on a construction site that, according to the schedule, there should be two subcontractors assembling two different systems for equipment in room W-0105? However, in the real world, these two teams could not work together because there was not enough space.

To make things worse, the #installation of components of one system may have limited the amount of space for the installation of the other system. Chaos arises. Neither the first subcontractor wants to give way, nor the second, because both are paid "per meter", or some other measurement, for their services, so the sooner they get it done, the sooner they can get on with the next job. The engineer in charge of #coordinating the systems is more often than not unfortunately unable to see the problems on the 2D drawings and Gantt charts because these clashes only happen when we take the construction program and the logistical issues into account, together with the real #3D dimensions of all services, including their required service areas - meaning in #2D these issues are often invisible and they only become clear in 3D or #4D. And this is where the logistical problem arises, since two companies are not working, and thus the work is delayed. The systems coordinator is also busy because they don't know how to solve this. The only reasonable solution is to assemble the two systems in parts and check for further collisions.

Theoretically, the problem was solved, but by analyzing the incident we can conclude that:

1. The subcontracting company is unhappy because they calculated for themselves that they will do a certain number of running meters of installation per day. Because of the situation, they will have to speed up the work on other sections to come out on top. It may come to a situation where they will try to do it faster on subsequent rooms, but the quality may then decline or they might cause further logistical issues. An overall balanced workflow between all subcontractors could come to a halt;
2. The coordinator in charge of installing the systems has finally solved the problem, but he is worried about what will happen next with the following rooms. The coordinator is not able to verify the drawings, because it is not on the documents that the errors occur, and each subsequent room that will have another collision could jeopardize the deadline;
3. Unfortunately, this can harm the entire investment if the systems in question are on the critical path of the schedule. When the situation repeats itself several times, the contractor will be forced to hire more subcontractors to simultaneously execute several rooms at the same time, which again can cause further disagreements or even issues.
4. Profit and loss balance:

• The general contractor will possibly complete the investment on time, but will put more strain on the budget by hiring more subcontractors than anticipated during the tender;
• In a situation where the investment is additionally delayed, the main contractor will have to pay the contractual penalties, in addition, it will exceed its budget because of having to hire more subcontractors;
• Subcontractors may ultimately also be unhappy, as their work will be done more slowly, so subsequently, the overall profit will be lower than planned;
• Unfortunately, there is also the problem of the shortage of #blue-collar workers, who very often abandon low-paying investments in favor of others, so with such aspects, current subcontractors may leave the construction site because it will be unprofitable for them;
• The investor will not be happy either, as the investment may have delays, the quality of the executed projects might suffer and the overall budget will increase.

If so, are we able to anticipate such cases?

Probably some of you have seen installation drawings, filled with systems:

Quite often in such situations in the drawing, it is possible to find overlapping installations that are at different levels. In such scenarios, to the rescue comes…

And as #BIM4D specialists, we can help you visualize the chaos and construction program to handle complex areas of the project before problems can arise.

We will focus one of our next newsletters on this topic and on how exactly this can be achieved. So, keep following our updates.

May BIM be with you!