Futile – Pointless, having no effect; achieving nothing
A few tiles (futile) have little effect – it's pointless, the room is too big.
Examples of futile in a sentence
The losing team made a valiant but futile effort to catch up to their opponents.
It is futile to wash your car on a rainy day.
The man’s futile attempt to escape his kidnappers ended when he fell down the stairs and broke his leg.