View Full Version : | Need Help Building Attic Grow Box |
jakezking
08-24-2008, 08:05 PM
Alright, so I'm looking to finally begin assembling ideas for an indoor setup. The setup will be in my attic. The attic has blown insulation, with no insulation between the rafters and roof decking, so it gets pretty hot during the Summer and pretty chilly during the Winter.
I don't know much at all about construction, but the family member who will be helping me put this grow together has extensive knowledge in construction and related fields. I think he has a firm grasp on how to build a good box, but I'd like everyone to throw their 2 cents into the mix, so we can build the best possible box.
I'm thinking about building between a 3'x3' to a 5'x5' box to be situated atop plywood decking secured to the joists. I propose the box to have hinged front doors to allow easy access in and out of the box - will use weather stripping around the doors to prevent light leaks. The interior will be painted with a flat white paint. The box will be insulated and air conditioned to maintain temps.
The grow medium will be soil, as I'm not comfortable with running a hydro or aero setup in my attic just yet. I propose to hand water the plants as needed, but may include drip irrigation on timer depending on how comfortable I get with the idea.
Now, I've read that 5,000 lumens + per square foot is recommended on lighting, depending on ability to maintain temperatures, so I will be looking at either a 600W to 1,000W MH/HPS setup depending on my choice of box size. The light will be suspended from the ceiling of the box from adjustable hangers to hang horizontally in the middle of the box. I'd appreciate any and all input as to favored/disfavord brands of lightbulbs, reflectors, cooltubes, ballasts, etc. Based upon comments here and there, it looks like HTGSupply is a reputable store?
Given that the box will be air conditioned, does anyone feel I should also use a cooltube or ventable hood or otherwise have any inline and/or exhaust fans? I'll keep an oscillating fan of some sort in the box to keep a breeze on the plants to increase stem strength and circulate the air.
Any and all thoughts, comments, suggestions, experiences, or anything else you have to contribute to my setup will be seriously appreciated. I want to build this box right the first go 'round, so I won't have to modify it much over the years. I know there are some folks in here with serious construction and engineering know-how, so I look forward to your input!
Thanks in advance for your help!
Dr.Hashman
08-24-2008, 10:02 PM
Right now I'm building a 7x4x7.5' box using 1x2's and 2x2's to frame it and I'm going to use to use a staple gun to put panda film around the frame making a sealed area inside for now.
I'm running a 250 HPS now and I'll put my 1000w HPS in when all my girls 8" or so since I have both lights already. I would do a 600w HPS if I was to start over with no equipment. A 600 HPS in a 4x4x8' tent would do nice. My next move up would be to buy another 600 and run both air cooled in a 4x8x8' tent.
You said that it was in an attic with fluctuating temps right?
A) Lung room. You can use air ducting and a fan to suck air from a room with temps at 78° to fill your tent with fresh air.
B) Cool/Heat air. Use a small AC unit to keep temps right nearby your intake.
C) Find another way to stabilize temps
D) Search the board for "temperature" and see how people handle it.
I'll try to give you some tips on making a box once I finish mine.
BeFree
08-24-2008, 10:45 PM
Do you have a fancy brick home with central heating and air?
Hehe, I've got some fine herb that for some reason triggered my DIY 6th sense.
Maybe I could draw an idea on paper, take said picture, and post for ya.
Be Good.:jointsmile:
jakezking
08-24-2008, 10:58 PM
Good Dr. Hashman and BeFree, I appreciate y'all's responses.
Dr. Hashman, my biggest threat in the attic will be temps. I was delaying any indoor plans for a long time because I didn't have any idea of how to deal with the temperature issue. My family member is the one who pointed out he could pull another duct line to the box, so with that issue solved I think this box should fall into place pretty well.
I would appreciate further input from you when you have time upon completion of your own box. First hand experience really provides better insight. I have very little experience in construction, but have gotten some ideas from this board - I can use all of the insight and ideas people can throw at me. Thanks!
BeFree - dude, I would appreciate any drawing that you feel like sharing. I seriously thank you for the offer and look forward to checking out your thoughts! Thanks again for your input and great share!
BeFree
08-24-2008, 11:42 PM
BeFree - dude, I would appreciate any drawing that you feel like sharing. I seriously thank you for the offer and look forward to checking out your thoughts! Thanks again for your input and great share!
In that being, thanks for responding so quickly and letting me know you already have the idea for running duct from your central air. :stoned:
Lemme come up with a few ideas. I'm being bugged by a few buddies to go take a couple bong rips. I'mma converse with a few of my nerdy counterparts.
But in a nutshell. Use the AC to cool the room/canopy in it's own ducting.
And use a inline vortex to pull air from a near source. (through the floor, *snicker*) So you are using the air from one of your rooms to separately cool the HID that you have in a cooltube ofcourse. With doing that, the AC will have much less problem keep your canopy at a stable temp. and maybe a oscillating fan or two to simulate a cool summer breeze to rigid up the stalks for the dense buds in the upcoming indoor season.
Be Good. :bonghit:
Dutch Pimp
08-25-2008, 01:30 PM
my biggest threat in the attic will be temps.
I agree with that statement, Jakezking...you must maintain a 70-85 degree zone for best results....:thumbsup:
also ...what about height?....tall plants/hot lights need their distance. 8-10 feet works great...anything less...you run into problems.
McDanger
08-25-2008, 02:03 PM
If you are running off your existing ducting for heat and air, make sure you put in a return duct also, and you probably want to put a carbon filter on that or your whole house will smell dank. Either that or you could probably use a passive exhaust, with filter do to positive pressure from the duct blowing in heat and air. If you do it taht way I think I would use a cool tube for the light ducted on both ends with a fan exhausting that right into the attic. You may have to damper the duct for heat/air depending on how warm it gets in there since heat rises and most likely your thermostat is on a lower floorand will regulate the temps based on that room, not the grow room temp.
jakezking
08-25-2008, 04:39 PM
BeFree, DP, and McDanger, thanks to each of you for your input. As stated above, I cannot get enough input and thoughts to ensure I do this attic box right the first time.
BeFree, I'm sure you came up with some dang fine thoughts following your bong hits, and I am looking forward to hearing same.
DP, I appreciate the insight into the height issue. I hadn't thought that much about height, as I am a firm believer in lst'ing. But, given your input, I may have to increase height as much as I can. The height would vary given the pitch of the roof if I were to build up to the rafters, but I should be able to build maybe up to 6 feet.
McDanger, I appreciate the thoughts about the AC ducting. I was thinking about the same thing as you, with regard to the smell seeping back through the ductwork into the house. I agree will need to prevent negative air flow. My family member has extensive experience with HVAC issues, so he's probably already all over this issue, but what do you think about running two narrow ducts from my main HVAC ductwork - 1 to service the grow box with a filter to prevent negative airflow, and 1 to allow an in-line fan to service the cooltube with another fan to exhaust the cooltube?
Thanks again, you guys, for stopping in to provide me some insight and help! I truly appreciate it! Keep it coming!
McDanger
08-26-2008, 02:49 AM
I don't know if I would use the hvac on the cooltube unless you only use a/c and no heat. You don't want to blow hot air into that cooltube in the winter. You might run one of the ducts close to the wall of the cab/room you are building and then just have an intake for the cooltube in that wall. Just a thought.
Thanks for stoppin by my grow. My leaves aren't gettin any worse so I'm not gonna worry. I think I'm only 2-3 wks from harvest anyway.
Keep in touch.
lunarose
08-28-2008, 07:36 PM
Jake, Do you have one of those whole house attic fans? The problem I see with your cooling set up is that your thermostat is in the house and I would think that during your hottest months you'll need your house temp to be way too cold just to get you attic to a tolerable temp. Not to mention your electric bill! Heating won't be as big as a problem during your winters since you are in the South.
ordeith
08-31-2008, 05:53 PM
This is a great thread - I think I am in the exact situation. I'm in Texas...gets pretty hot here and temperature control is going to be my main issue. I don't have the HVAC experience, nor do I have any ducting going to my crawl space (seperate from my main attic).
Any ideas on how to maintain temp control without any access to HVAC duting?
anbesol
08-31-2008, 06:26 PM
Dude! Run a 600 Watt!!!!!!!! they give you the most lumens for your buck! Make sure you have ventilation going up there for the winter so it doesnt get too cold! you need to stay at least 68 degrees at nite for cannabis!
Powered by vBulletin® Version 4.2.5 Copyright © 2025 vBulletin Solutions Inc. All rights reserved.