Quick question about lighting and ventilation

Hey guys im looking for some advice as i'm new to the indoor growing scene, i have just purchased two 1000w Prolight HPS lights with reflectors and have a loft 14ft by 14ft. I've lined the walls with tin foil (dull side out) and intend to grow around 40 plants, will this be enough lighting? I'm also worried about the amount of heat generated and my electric bills! Will i require two fans (one to extract and one to put fresh air in) and should they be running all the time or can i set them on some sort of timer, if so should they run simultaneously or should they come on at staggered times? Sorry guys one more quick question, how long should i wait from germination before exposing the plants to the 1000w bulbs?

I'd really appreciate it if someone could share their expertise with me.

Happy Growing!!!

If you don't stand for something, you'll fall for anything!

not an expert, but I would have the both vents on at the same time.

Reason for this is simply because your lights are going to be on either 18/6 or 24 hours a day. If there is nowhere for the heat to go, it will get stifling... The light's wont produce an intense amount of heat, but they could easily burn your plants.... Plus if its in the loft, then the insulation could ignite.
It's not going to cost a LARGE amount to run them.. Dunno if its enough for 40 plants, guessing you would do SOG, in which case it should be alright I suppose.

To be honest, sounds like your planning on dealing. Nobody goes from nothing to growing 40 plants. Plus more plants = more chances of males = more chances of fertilization, not to mention possible bugs, illnesses and whatnot, so you need to KNOW what your doing, growing for yourself is one thing, but wanting to supply to someone else means your gonna have to know what your doing.

woo man, 2000watts is a bit much for 14 by 14ft. you may only need one of those lamps, but the more the marrier. it's pretty hard to give a cannabis plant too much light. the most common problem with too much light is too much heat. utility bill will be a lot higher, especily during the veg. phase. i would guess a buck or two a day. you can buy timers for your fans. if you want to go all out their are some really nice climate control timers that you can set your fans, co2, temp, and humity all at once or you can go the cheap way and buy some more light timers(be shure they can be cut on and off several times a day)and use them for your fans. alough with that much light you may need them on the entire day. remember to cover the smell of your exuast fan so not to alarm your neighbors.

Cheers for the advice guys, how often should i turn the fans on for ventilation?would one hour in every six be sufficient or do you think i should run them more often? I am not planning on dealing by the way i just plan to grow copious amounts of weed for myself and a few close friends to enjoy throughout the year.

Thanks again

yes, that sounds fine for the vents. unless it gets to hot.

How many friends do you have? 40 plants is alot of weed. You'd have enough to deal if you just grew a few plants as long as you knew what you were doing.