Question about crack in tile grout in shower cubicle

[jameslpool]

Hi, I have moved into a new build property about 6 weeks ago, I can't say I did or didn't really notice before but in the shower cubicle I have noticed that just above one of the bottom tiles there is a thin crack running along the grout (prob about 10cm long). Can anyone tell me if I should be concerned about that? I'm I biggish guy and I am hoping that it's not my weight on the shower base that's caused it? Would that be possible? I am assuming probably not as I am not sure how that would effect the wall as such? I am going to have the builder look at it I'm guessing they will probably just get the tiler to just fill the grout in again do you think? If that is what they do should I be happy with that or could it be a bigger issue?
Also how long does grout take to dry and set?

Regards

James

 

[PrenticeBoyofDerry]

Very likely a shrinkage crack, it can happen if the grout lines are either too big and the grout is not mixed correctly.
Grout would under normal condition, dry enough within 24hrs for the shower to be usable.