Honestly I have no idea what it means to "repair the construction". Were they building something and it broke? Why would you ever need this sentence in day-to-day life?
Prolog Digital's Hebrew-English Dictionary app offers "structure" as an alternative gloss. That should work a bit better.
Anything that is built is a מבנה, including bridges, road interchanges etc. (but not ships, or roads). A בניין ia just a building.
This sentence should be translated as "repairing the structure" or maybe "repairing the building". A "construction" would only be used to describe something in the middle of being built but not yet finished.