like people have said before i dont think that they would really look at your house and say "hes growing pot" there are alot of things in a house that put off more heat than your lamps..the heater might be a little hotter but still. how do they not know that is an actual room and you were chillin with your reading lamp on and got cold so you turned a heater on? if your really worried about it get some thermal block you can get it at home depot or lowes and i dont think its very expensive
well i live in a single story house with a small attic and if they looked at it from an angle they would be able to tell its higher than everything else but im gonna try it out anyways as soon as i figure out how to get a medium sized box to fit through a tiny square hole