Steady and satisfying progress is predicted by a dream concerning construction labor; however, if the workmen were idle, or there was an unpleasant atmosphere or aspect in the dream, it indicates an emotional upset.
To dream of having labor pains is a forecast of achievement but only after hard work.
A dream concerning labor politics signifies a coming improvement in your circumstances.... The Complete Guide to Interpreting Your Dreams
It could be that you are assuming some new position at work and the dream is giving you the necessary indications and tools so as to improve your methods. On the other hand, dreaming of a factory full of workmen signifies that you will soon complete your most ambitious projects; meanwhile, if it is empty, you should put more interest into the job.
If it is you who is occupying the factory, you will arrange a way to leave the situation.
Dreaming of workmen or of a factory is a very good sign. It foretells happiness in business and in love.... The Big Dictionary of Dreams
To dream of workmen may represent that the dreamer needs to be working on themselves. For example, if the “men working” signs are up while no one is working, laziness and irresponsibility may be at issue.
The workmen may be drilling into the earth, which suggests that the dreamer may be embarking on an exploration of the unconscious mind.... Dream Symbols in The Dream Encyclopedia