In short, no - wood flooring needs to be acclimatised before it is fitted. This means giving it time to adjust to the atmospheric conditions of the room where it will be installed so that this doesn't happen after installation and cause unusual movement.
The reason for this is that wood is a hygroscopic material that responds to change in temperature and humidity. If you bring wood flooring into a room that has stable conditions, and it adjusts to these before it is fitted, you should only expect to see small variations in the natural gaps between the planks or blocks as it responds to seasonal and atmospheric changes.
If you don't let wood flooring acclimatise before fitting, then it will adjust to the conditions of the room afterwards, and this can cause more significant movement in the floor, outside these norms.
Similarly, if you acclimatise or fit wood flooring in a room which doesn't have stable conditions, such as one that hasn't had the heating connected or where the plaster is still drying, then once these change it will adjust to respond to the changes and this can cause more significant, unusual expansion or contraction.
So how do you acclimatise wood flooring ?
Before you bring wood flooring into a room to acclimatise, it needs to meet normal living conditions - which means it should be sealed, dry and heated as will be the case once the floor is fitted and the room is inhabited. The room temperature should be between 15°C and 24°C and the relative humidity (easily measured with an inexpensive meter) should be between 40 - 65%. It should also be free from damp.
You then need to unwrap your wood flooring, and lattice stack it (stack it criss crossed) so that the air in the room can circulate round it. If you don't do this then it can't acclimatise evenly.
Wood flooring will take 7-14 days to acclimatise. In new build properties or those where new heating systems, new plaster or concrete have been installed, you should err towards the upper end of this spectrum. Similarly if you have chosen wide wood flooring.
If you have any specific queries about acclimatising your wood flooring, please contact firstname.lastname@example.org for advice.