Help: Temperature control for a unique grow situation

[storminmormon]

I recently got the green light from my SO to do a 2x2 footstamp grow at a house we are renting. There is a chicken coup in the back yard that is capable of housing the grow. The garage does not work, unfortunately. I will be measuring the coup this weekend. I can buy a tent but I would prefer to build a custom enclosure myself with insulation. I have a clone source and am going to do a 1-2 week veg and flip to flower to keep the plants low height.

Here's my problem. I want to have this built buy the middle of january and i live in norcal where it can get a little too cold. I want to use LED lights to save on electricity and because I've wanted to do LED for a while, and for other reasons like having more room to play with in my small box.

Even if I insulate my box my intake is going to dictate the temperature of my box. I am looking for a low power consumption way to heat my intake air in the winter. I thought about building a small chamber on the bottom of the box that acts as an intake(light buffer) and a heater. I just don't know how to go about that right now.

Any ideas? My friend recommended I go to HPS, but that would make my bills hard to justify, and the summer would be much harder, and I have height restrictions. I'm weighing doing soil vs a home made hydro setup. Soil has bug risk. Hydro is new to me, but I've read some stuff on these forums.

 

[Mikell]

How much do you like digging in the winter?

Burying a section of pipe into the ground to function as passive heating for intake air might be feasible if you're a mole. Would also advise slowing air exchange down to the absolute minimum.

Although, I would hate to see the look on your face afterwards if it failed to raise temperature adequately Swing from outdoor to desired indoor temperature would need to be moderate.

 

[storminmormon]

Digging here isn't bad. It's not frozen ground. I've also been researching sealed room grows.

Maybe a metal filament I could run in my intake ducting/enclosure to heat the air if it's too cold.

edit: With LED's in the cold I could slow my intake down a lot I would assume.

 

[storminmormon]

maybe something like this in the grow room hooked to to a thermostat?

http://www.amazon.com/Sengoku-SP-160-Panel-Electric-Heater/dp/B0014FGV9Y/

 

[coldcanna]

You can get a small ventless propane heater for 100 bucks, no electricity required.

 

[theother]

Either a small propane heater (build some light proof metal enclosure, and keep your fingers crossed) or just go hid. Maybe try out the 315cmh's there are a couple of threads on here about them. It just seems a shame to put $ into heat when you can spend the money on more wattage and get the heat you need.

What are your summer time temps like? I kind of feel like a chicken coop would be hard to keep cool even with no light in it if it gets up to 100

 

[rangergord]

Energy is energy. Propane is not cheap. The best way would be to have a veg space half the size of the flower space and run a small 125-250 watt grow lamp then ventilate the veg space into the flower chamber during the dark time. I use an electric heater in my closet. It takes at least 500 watts. A grow lamp for vegging would not take much more in terms of cost.

 

[storminmormon]

Thank you for the advice everyone! Good news! I measured the coup and I can build the enclosure 5 feet high. I thought it would be more like 4 feet. It can also be 2 feet by 2 feet.

Here's what I'm thinking based on the advice that's been given:

My friend has a 250 watt setup with a ballast I can use. I am tempted to use that, pay for the extra power but I wouldn't have to buy bud anymore. Would a 2x2 be too small for that? It's 62.5 watts/sqft.

If I can't do that...

(16-20)"x(16-20)"x5' cab with 150W HPS, inline fan, self made scrubber, intake on the bottom of cab that comes from a small "cab" I can build on the side of the box that has a filtered intake and houses the ballast to warm the cold air coming in. I can add ac in the summer when needed.

4 clones from local dispensary in 2-3 gallon pots(need to decide based on space how long i can veg without getting too close to the light in flower, then decide how big of pots to use based on that. Any advice?).

 

[stoned-trout]

use small hps now, use led in summer

 

[storminmormon]

I'm thinking the 150hps for winter, led for summer as well. I want to own what I'm using. I guess now I have some work to do!

Since I have 5 feet to work with. The lamp is 5 inches(+12 length from plants)=17", The pots will be around 7-8 inches. That means I have some space to try some scrog with.

If I pick an indica heavy strain from clone could I get away with a two week veg, or do the plants need to be bigger?

 

[Avinash.miles]

hps is not that expensive to run, esp. to light a 2x2 area....

have u thought about using a 315w ceramic metal halide? they create some heat, nothing like an hps... but perhaps enough to create that environment you need. also imo the philips 315w ceramic metal halides are the real gamechanger when it comes to efficient grow lighting.
and LED's heat levels vary model to model, ime.

 

[theother]

hps is not that expensive to run, esp. to light a 2x2 area....

have u thought about using a 315w ceramic metal halide? they create some heat, nothing like an hps... but perhaps enough to create that environment you need. also imo the philips 315w ceramic metal halides are the real gamechanger when it comes to efficient grow lighting.
and LED's heat levels vary model to model, ime.

I vote 315cmh also. If your gonna go led at least get in touch with rives or one of the other well versed led members here and get the rundown on what's what. Led is definitely one of those things where it can be hard to quantify what's legit and what is a scam.

Fwiw my honest vote is always horti eye hps 1k. Go with a 1k and some t5's, cost you 200-300 a month. Grab a 315cmh or two before summer hits.

I know that's not what you want, just feel like it would be remiss to not throw it out there. One final thought, craigslist is FULL of guys who overbought without learning to garden and if you want to go that route it can be a super affordable way to go. Honest value is 100 a piece, one for a decent air cooled hood, and 100 for a reliable digital dimmable ballast. Obviously don't pay a thing for the bulb in it, and toss that shit and spend $80 on another one.

 

[growshopfrank]

Just a thought but an old refrigerator or freezer with a few mods would make a nice inclosure and its insulation should make temperature control easier