Requirements for HF radio transceiver room

Tweet

We are in the process of intalling a TCI-540 omni-directional antenna and CUBIC COM5000 radio system with kW transmission power. The antenna center is 70m from the radio transceiver room and there is an RF cable from the center of the antenna to the equipment room. I understand that we need to completely install a copper plate to cover the entire building from wall to ceiling. Is there any specifica reason why this should happen? And what's the significant impact of not installing the copper plate?