Usually this type of room is designed by a manufacture together with architect , http://www.inomhusmiljo.com/att/Sng.pdf
My job is to ventilate the whole room, with this system that circulate and clean the smoke its no problem connecting the room to a central ventilation system.
I see the price starts at 62 000 SEK + VAT, thats around 6000 Euro + VAT.
Helge