250 Watt or 400 Watt Attic 1st grow

[McStoner420]

Hello everyone this will be my first post, been doing alot of reading on grow room setup and i want to build a grow room in the attic space i have. Dimensions are 8 ft wide 6 ft. long and 4.5 ft. high. The shape of my grow room is going to be that of a triangle i already have plans for good ventilation (i have plenty of vents i can hook up to) and i plan on insulating the outside walls of the grow room. I want to do a SCROG setup because i only have 4.5 ft. of room to the top. I plan on growing 4 plants in 2 separate rectangular trough pots under the screen with 3 gallons of soil to each plant. The question i have today is about lighting. I was earlier thinking about just a single 400 watt HID for all 4 plants but with only 4.5 ft of space im skeptical if that will be enough room to have it without burning the plants. Now I've read that 250 watt HID could get closer so i was able to find 2 250 watters for about the same as 1 400 watter and I figured the light coverage would be better having 2 lights closer to the 4 plants plus 2 250's is 100 watts more than a 400 watt. Is that more lumen's too?

 

[andytoker]

hey mcstoner, i grow in my attic too, in a cabinet within the triangular shape of the roof space. i use a 250 over an area about 2x2.5 ft. 2x250 will mean you can cover about 2-2.5x5-6ft in a decent fashion (2x250 will give out more light than 1x400). 250 needs to be 6-8" above the canopy. i also use scrog (modular where the screen is attached to each pot) and get great results.

the main thing to consider in the loft is environment. it gets very hot up there in summer and cold in winter - even with insulation (i have my cabinet inside an insulated 'room' at one end of the attic). my best advice to you is to try to duct air up from the house into your grow as this will be a much better temp. you can then exhaust into the rest of the roofspace without any bother - in fact it helps ventilate the loft.
unfortunately my grow diary is at another site and i dont think they will want me to link to it.

A.

 

[Steve Z]

man that sounds super crowded in there.

id do;

1 400 watt
1-2 plant in 3-5 gallon pots

scrog.

OR

since you only have 4 1/2 feet tall that may cause problems....

i mean it would be twice as safe twice as much room and twice as sketchy if you just did it in the house.... just my 2 cents though...

 

[andytoker]

i think it sounds fine on the plant count. i do 4 plant modular scrog under a 250 with 3-5 gallon pots, and average around 3 ounces off each plant. you need big pots for scrog.

attic can be awkward but is very stealthy and its my only choice for a grow. just here to tell you it can work just fine.

 

[McStoner420]

Thanks for the replies. I have a ducting outlet already in the roof that im going to leave out of my growing room and hookup a squirrel fan to suck hot air out of the attic during the summer. My grow room exhaust is going to either get hooked up to my dryer outlet or hooked up to one of the vents that go under the overhang of my roof. The entrance to my attic is in the laundry room anyways. I was thinking 2 250s cuz i wanted to get the most light coverage for my buck cuz like most growers im on a budget lol. An 6 to 8 inches from the tops sounds good being that i only have 4 1/2 feet to the top. I live in colorado so the winters are cold but the summers are nice and it doesnt get humid and hot like lets say florida. Wanted to do 3 gallons to each plant, i read a general rule of thumb is 1 gallon to each foot you want your plant to grow an i think a scrog will help me stay under my mark. Gonna grow a short/medium indica. My walk in closet would be a good place to put a grow tent but my wifes approval for that wouldn't go down to well for me lol so i gotta do a attic grow up and outta the way from peeping toms. Its very doable from what ive seen and measured up there i just need to get the room setup on the other side of the attic im building a veg/clone room using t5 flourecents. More than happy to read your grow diary if you wanna pm me the link. Still got lotsa research to do wanna have everything ready be4 i even think about putting plants in there