The feed of the unscrambled terrestrial TV channels 1-5 is due to be disabled. It's there as a legacy thing from the old analogue TV over cable services. New digital installations aren't having this functionality installed.
If you need to distribute TV to 5 different rooms, if you must have cable, then it sould cost a lot with separate STBs in each room

Alternatively you could feed the RF (ao-axial) output from one STB into an amplifier and splitter which from there sends the signal to the various rooms. Only problem is every room can only see the samse single channel being output from that one room.
I'd suggest going back to a rooftop aerial if you only need channels 1-5 in other rooms. If you add the roof top aerial signal into the output feed from the STB RF as outlined above, using a combiner, you start getting the best of both worlds.
An alternative might be to consider freeview for your less important rooms.