Reflective insulation good enough?

[kaivorth]

Making a grow box, is this going to do the trick? Will have 2 MarsII Hydro 300 LED's. Hoping to trap the heat the LED's make in the winter. Gets down to 40F in the house in the winter at times, and I figure I could always have one on, and alternate between the 2 to keep the heat going. Let me know what ya think. I'll get Mylar in the summer when I don't need the insulation.

 

[Papageno]

So do some research on this but you would be surprised. White paint works better than almost anything. Best bet is to use a fan to adjust temps and use something easy to clean between grows. Build up on the surface dramatically impacts reflectivity so it should be cleaned between grows.


Conducted tests for best reflective surface for your lights/hoods

 

[Marzbadrock]

On the back of that insulation it says "caution combustible " so I'd recommend another route. You can build a box and paint it white or get a roll of mylar from your local hydro store for 20 bucks.

 

[Amadeus Forzin]

White paint is what I use, I was gonna switch to mylar but getting good results do reluctant to change it. If your insulation board says combustible, I'd be steering well clear. Best of luck in your adventure. We are all here if you need us.

 

[rillos]

Yes that's fine to use, plus it will trap most of heat if you seal it. But you will probably still need to add some heat.

 

[Mtn Dew]

I agree with The VillageIdiot. A little video to add to his read:

 

[kaivorth]

You guys are awesome. Questions still.

It's obvious this box won't get too hot, so does the combustible warning matter? Sounds like white paint is the way to go instead. Does anybody know of good paints for rigid insulation?

 

[Papageno]

SOOOOO

I found this great stuff...Home depot has a great one to...but I would recommend NOT using normal paint. They make a paint specifically for Roofing that is designed to be reflective and also reflect UV rays to help with economical cooling of a building. And to boot since it is a specialized outdoor paint it is also mold and mildew resistant. So look up reflective roof paint online and you will find some cool stuff out there. But it aint cheap and it comes only in those 5 gallon buckets.

Standard Flat White will get you probably as good of results.


Typically with the light on you wont have a heating issue. I run my lights at night which helps. So when they are on you should be okay by adjusting the fan. When they are off some people run a small oil or electric space heater.

So if you keep the house reasonable during the day (when your lights are off) and the light warms it at night (when your furnace is off) you may be fine.


The real problem with insulation is it just wont work. You most likely will have a vent fan running 24/7. So any heat built up will be removed as soon as the light turns off. So you want to consider something a bit more forced like the heater. I run in my garage and I have a 2 story house and rooms over my garage so it doesn't get that cold in there really during the day. It is 36 outside and my tent is at 62 right now with the lights off and vent fan running. But if I ran the lights during the day and let it cool off at night I might have a problem on my hands. I have a fairly well insulated garage and the light being on all night actually keeps my garage nice an toasty and that keeps it warm well through the day even after it is off. But I am running a 1000W DE bulb.

 

[kaivorth]

SOOOOO

I found this great stuff...Home depot has a great one to...but I would recommend NOT using normal paint. They make a paint specifically for Roofing that is designed to be reflective and also reflect UV rays to help with economical cooling of a building. And to boot since it is a specialized outdoor paint it is also mold and mildew resistant. So look up reflective roof paint online and you will find some cool stuff out there. But it aint cheap and it comes only in those 5 gallon buckets.

Standard Flat White will get you probably as good of results.


Typically with the light on you wont have a heating issue. I run my lights at night which helps. So when they are on you should be okay by adjusting the fan. When they are off some people run a small oil or electric space heater.

So if you keep the house reasonable during the day (when your lights are off) and the light warms it at night (when your furnace is off) you may be fine.


The real problem with insulation is it just wont work. You most likely will have a vent fan running 24/7. So any heat built up will be removed as soon as the light turns off. So you want to consider something a bit more forced like the heater. I run in my garage and I have a 2 story house and rooms over my garage so it doesn't get that cold in there really during the day. It is 36 outside and my tent is at 62 right now with the lights off and vent fan running. But if I ran the lights during the day and let it cool off at night I might have a problem on my hands. I have a fairly well insulated garage and the light being on all night actually keeps my garage nice an toasty and that keeps it warm well through the day even after it is off. But I am running a 1000W DE bulb.

I'm getting conflicting answers about insulation being worth it or not. However you did say running a fan will vent out all the heat for the most part, which makes sense. I just hate having to keep a heater on all the time just to heat these plants.

After some pondering, I think I will buy a small oil radiator. I will still make a grow box out of some insulation, I will just paint it white or tack on Mylar sheets. I will also use LED lights still. I hope to have the fan on when the lights are on for circulation, and turn the fan off at night to let the oil heat stay inside. In the summer time, I won't even need AC with this setup I believe. I live in Vermont.

This sound like a decent setup?

 

[Papageno]

I can't really help on that. I don't use LED's. I am an electrical engineer so I am interested in trying them but I have top of the line HID equipment. One of these days I will get some LEDs to mess around but I don't need them today.

I have used Mylar and that works for maybe 2-3 grows before it is real bad and needs to be changed out.

One Big thing in indoor growing is efficiency. If the light is reduced by 10% then the yield is reduced by 10%. Now we are talking about reflected side light so not as big a deal but anything you do that is less than optimal means you have to adjust your recipes and plans.

For example you may find a journal where someone ran the same strain as you and they are using the same medium (lets just say for arguments sake you both are running the same identical off the shelf RDWC system). But they are using a larger space with more accurate climate controls and better air flow and 10 % more available good lighting. You can not follow their program exactly. They are running a more efficient room that will have more photosynthesis with faster more vigorous growth. So when they say on week 4 they upped the PPM to like 700 and it just barley started to show signs of burn...if you did that you would have substantial burn most likely.

So just understand (myself included here) that when we build up a micro garden setup we have already put major constraints on ourselves that prevent us from growing ideal plants. We have to do what we can to optimize the space we have and get as close to an ideal as possible and compensate for all the things we can't or don't get right. Usually that means lowering the nutes down by a non-trivial margin.

 

[kaivorth]

I can't really help on that. I don't use LED's. I am an electrical engineer so I am interested in trying them but I have top of the line HID equipment. One of these days I will get some LEDs to mess around but I don't need them today.

I have used Mylar and that works for maybe 2-3 grows before it is real bad and needs to be changed out.

One Big thing in indoor growing is efficiency. If the light is reduced by 10% then the yield is reduced by 10%. Now we are talking about reflected side light so not as big a deal but anything you do that is less than optimal means you have to adjust your recipes and plans.

For example you may find a journal where someone ran the same strain as you and they are using the same medium (lets just say for arguments sake you both are running the same identical off the shelf RDWC system). But they are using a larger space with more accurate climate controls and better air flow and 10 % more available good lighting. You can not follow their program exactly. They are running a more efficient room that will have more photosynthesis with faster more vigorous growth. So when they say on week 4 they upped the PPM to like 700 and it just barley started to show signs of burn...if you did that you would have substantial burn most likely.

So just understand (myself included here) that when we build up a micro garden setup we have already put major constraints on ourselves that prevent us from growing ideal plants. We have to do what we can to optimize the space we have and get as close to an ideal as possible and compensate for all the things we can't or don't get right. Usually that means lowering the nutes down by a non-trivial margin.

I'm doing everything I can to optimize this grow by not breaking the bank. I wonder how LED's really compare to HID though.

 

[Papageno]

Well there is a lot of data to suggest LEDs are better but you need multiple types and they are very expensive relatively speaking last time I checked.

A decent HID setup is dirt cheap and you can run just one type the whole time. And I don't know how long you have been smoking but most of the great weed grown indoors has been and continues to be HID.

LED is great for a micro garden like you are making. But you can get the absolute top of the line best HID setup out there for the price of a mid range LED. You can get a decent starter HID setup that can get you a pound a plant for well under $200.


I am old so I still grow HID but that doesn't mean I am right. I just know you can get great weed from HID and most if not all the weed I have ever smoked is from HID or the sun.

Whenever I look up the top of the line LEDs I can't believe what they are charging for them. And lights are the last place to skimp. You want to get the best you can afford no matter what you choose. If you go HID put your money into a great bulb.

Here is a good video on HID

I will never use a single ended setup again. Only Double Ended bulbs for me from here on out. But then you must have eye protection.

 

[lexort420]

Well if you are cheap like me you could just line your grow box with emergency blankets thats what i use. Providing you have venting it should keep it warm enough. I currently use cfls but gonna be switching to leds for flowering soonish lol.