Aerial reception and TV set up

[HappyFace]

Current Set up - Living Room (TV, Cable Box)
Conservatory � (TV connected to Cable Box via splitter)
What I want is the above but also
Bedroom (TV with integrated Freeview), Bathroom (Tilevision waterproof TV with ability to receive either Freeview or Cable channels).
I have an aerial in my loft. I also have a reflective foil type loft insulation attached to my rafters that affects considerably the reception I get on Channels 1-5 when not using the cable box.
To sort out the reception in the bedroom and so that I can receive clear Freeview channels, I was going to get one of those amplified portable aerials to stand next to the TV. However, the TV & aerial are behind sliding cupboard doors, opening when in use.
Is the portable aerial sufficient to receive clear pictures on bedroom TV?
Should I consider getting the loft aerial moved on top of the roof? If so roughly what sort of price would I be looking at?
If I were to connect the bathroom TV via the splitter on the cable box, would I lose the clarity of the picture, in the bathroom, living room & conservatory?
Sorry for the multitude of questions, I am getting conflicting stories from Sales assistants in the high street shops. Thanks