Question for my Canadian Comrades

So with it being winter here now in Canada and my part of the country is experiencing a cold snap, -40C with the wind... My question is if anyone has tried to grow room in an uninsulated shed?

I'm thinking if you make an enclosure in the shed made out of polystyrene insulation or any other high R rated insulation, use an HID lamp for light and heat, could the heat generated by the lamp bring up the ambient temperature in the enclosure to support growth? I would think instead of venting the heat out, use the fans above the fixture to push the rising heat downward.

I'd say the temp inside the shed might get as low as -20C so to support decent growth the ambient temp must be around +20C so will the HID lamp push out enough heat to raise the enclosure +40C ?

I know this would be ok of a 24/0 veg stage, but going to the 12/12 for flowering a small area heater would need to be on a timer/thermostat once the lamp goes off and ambient temp starts to drop.

So anyone ever consider this? Any ideas/comments are appreciated.

yes my son i live in canada and currently have a grow i just started on nov 25. in my shed. my shed on the other hand is insulated but this doesnt really matter as long as like you said the grow box is insulated. infact my grow box is insulated by some r28 insulation and a few layers of mylar emergency blankets. i have my veg chamber on the bottom with 24/7 light with a light sealed vent into the upper flowering chamber im hoping the heat from the lower chamber will keep the flowering chamber warm aswell during dark time. check out my grow journal i think ull find it quite interesting. any questions are welcome ill be right back after i go check my lil one out and smoke a spliff.... https://www.rollitup.org/grow-journals/141318-winter-indoor-outdoor-2x-400w.html

That is quite the closet you have going on there... Very nice!

How low does the temp get in your shed at night? I know mine with it being poorly insulated probably gets to -20 some nights, especially cold ones like tonight -40 something with the windchill.

Have you taken a temp of your flowering area yet to get an idea of how cold it will be with no lights on?

I as well have two 400W MH lamps, I think they're almost identical to the ones you have, was planning on holding off starting till march when temps aren't as cold, but I got the itch to do some growing. I'm in the process of building a batwing reflector for my two fixtures. 8" vent bent in two and painted white to focus that precious side light from the bulb to the lovely ladies.

I'm going to take some pic of what I'm starting out with and do the whole journal just like yourself and hopefully all will work out great.

You MUST live in the same town as I do, since we are supposed to have -40 to -45 tonight.

I wouldn't reccomend it at all. It's way too cold here to do it...indorrs is the only way unless you have a nice greenhouse setup, or a nicly insulated shed.

Quite plausible...

Interesting idea but insulation is pretty cheap, why wouldn`t you just insulate the shed first.

insulating the shed would help, but you still have to build another insulated box in the shed. I wouldn't have enough heat generated by my 2 400W MH lamps to heat my shed to 20C. So I'm just using the highest R rated insulation for the box. I'm growing for personal use.

Keep us posted, I'm intrigued! I've never tried a grow like this, but make sure to insulate the hell out of the floor if you're going to give it a shot. I've been in many an ice shack where my body was warm but my feet were ice cubes.
I have grown underground throughout the winter and it stayed warm enough, it just wasn't very fun when the snow melted....

Yeah, I'd like to see how this goes. On an average day I think you'd do alright but there are those -20C days where you want to make sure you got a portable heater in there and were available to monitor it more closely.


Edit: It keeps throwing my posts into the second spot on threads

yup my shed drops way below -20 even with it insulated with r28 but i can deff notice the temp change when i walk near the grow box... i had a diff grow box out there and insulated it with r28 also and temps were way to high with the 2 400w mh. so i built this box using some r28 thinned out and mylar emergency blankets and with a small heater set at 25*c for security the temps stay around 30*c and 50% humidity.... its working great considering the fact there is no shroud on my lights and no cooltubes or vents just so happens that the cold weather balances temps perfectly... I will be using smaller like 175w mh for veging and hps flowering with cool tubes to fight the heat of summer.

Well where I'm planning to do my grow is underground, but with -45C windchill values I'm scared my plants won't have enough heat for optimal growth. Once I have my lights setup I'm going to run them on a 18/6 timer and put in a thermometer with max an min values to see if I need to build an enclosure in the underground building.

You'll definitely need to insulate very well, and have supplemental heating when the lights go out. If you're down underground, the wind chill factor doesn't mean anything anymore. Just worry about the temp w/o the wind chill.

I just got my remote temp probe in the underground grow area, its telling me that its about 15C in there right now and its currently -30C outside. There are no lights in there, just the frosted walls near the upper half, the rest is quite comfortable. Looks like some mice got in there at some point, looks like I'll have to do some cleaning and straightening up down there before starting my grow. No one has been in there for about 10 years, so I think its due for a cleaning and some utilization.

so you have found a more suitable grow area. very nice and low key aswell since there are plenty of heli and planes with IR sensors in canada.. i happen to know the guy who fuels the plane in my area....... i should get him to put 10bags of sugar in the gas tank lollllllllll!!!!!!!!! I just took my first 2 clones from my lil one today.....

Its very low key... only disadvantage is the long walk through the snow to get to it. I guess I'll have to blow the snow and make a path.

I picked up two 400W MH lamps today... Did some shopping at home depot and found in the ducting area a piece of galvanized aluminum used to shield joists from hot surfaces to use as a reflector for my lamps. I just have to put a few bends in it and mount it to the fixture. I was originally going to buy a 8" vent and just bend it in the center, but I think this flat piece will allow me to make a more suitable reflector.

very nice idea i have been thinkin of what to use as a reflector in my flowering chamber for a couple a days.... i still got a couple weeks till i gotta make up my mind but that sounds like an ight option.........

For $4.49 you can't go wrong... And I was in there to buy the 8" vent for $10.64. I turn around and voila, there was a nice flat piece of galvanized aluminum sitting there! Figured I'd test bend one to get the best reflector and then go out and buy another one bend to shape and paint with high heat white paint for better reflection.