HELP..where do i ventilate

hi i have a room in my celler. measurements are: 5f length x 4f width x 6f height. im gona use the Atami Wilma 8 Pot Hydroponics System and Sun System VII 800 Watt Super Spectrum light. i like this light coz it uses both ends of the light spectrum of MH and HPS 2gether.i dont mind paying xtra for bigger buds. i dnt know how im gona ventilate, they is no gaps or windows in this room, the only opening is the door from my celler to the room (it used to be a back door leading to yard, but has been bricked up) i want to ventilate away from celler. so i plan on knocking a brick out and running a vent pipe inside a fake drain pipe, up 2 the top of my kitchen roof( its an extension, so its not 2 high). but how big does the hole have to be? and how do i do all this.its the only thing i cant work out. oh and anuva thing do i have to get fresh air in, if so should i make 2 holes in the wall? 1 hole 4 air in n 1 hole 4 air out. plz help thanks here are pics

i just gave you an answer in the other thread you started saying the same thing as this....... only put one thread up, no need for 2 threads stating the exact same shit.

yeah i thought i put it in wrong place,thought grow room design thread mite b better..... as 4 your idea, sounds good but i want 2 take the fumes n heat away from my celler. is they a way to decrease the heat b4 it goes through the vent i will make

not unless you use an a/c unit. or throw some ice up in there, LOL.
the only way to decrease the heat is to let it dissipate throughout the house or outside