words that irk me

In construction, I have known guys that use and fuckin frequently. It sounds so ignorant.
Over here at this wall, you need to run a row of blocks and fuckin at 28 inches to center......and fuckin six feet and down for the cabinet mounts and fuckin A-34 brackets at all 4 corners.
WHAT does And fuckin add to the sentence ???
Now that I think about it. That word is way over used on the construction site. By everyone. Still haven’t figured out what sex has to do with any of it.