does glass stop heat at all?

I need to make a stealthy grow box for the basement and im using a 400hp, so how can i ventilate this guy quietly to keep heat out. I know your gonna say small computer fan or whatever but if the top of the box is made of clear glass will that block any heat at all from getting in?

i know tinted windows can keep heat out but is clear glass absolutely useless for keeping heat away or what? if so are there any other ways i can keep my grow box cool without alot of noise?

thanks alot guys and gals,
z

glass is conductive

Even if you had the lights 10 feet above the box, shining into it, it will get hot. Think of a greenhouse outside- sun is millions of miles away. If you mount the fan deep in the box, it will be much quieter. I have a bunch of PC type fans, for several set ups, all mounted inside, blowing into 12"-24" long flexible ducts, through wall, etc- you can't hear anything unless you're right next to the outlet. Most of the noise is from vibration, not the airflow. Hanging the fan with o-rings/ HD rubberbands or such will help too.:jointsmile:

the best thing i can think of is a "cool tube" that you place around your HID bulb. I would think that that is ur best bet. good luck!

Glass also eats light.... Taking away from the rated lumen output of the bulb.Cool tubes are great if you have limited space.Still you should have some type of ventilation other than the one you would use with the tube.You have to replenish the air,not just fan it around.Just a few things to ponder on.A 265 cfm fan would work with the tube.You should go with the 465 and a wye inline with flex.Good luck with ya grow!

Ga Grown!:thumbsup:

Glass definitely is not conductive. Look at the top of your telephone pole. The wire is wrapped around glass that is screwed on to metal, at least if your power lines are old. It is also a very good insulator against heat but wont work for your application. As someone already mentioned, you are losing lumens, but an inconsequential amount if the glass isn't too thick. While that is going on though, you are also filtering out harmful UVB and UVC radiation that is wreaking havoc on your plants DNA. That said, it isn't going to make your grow room cooler. It may take some heat stress off the meristem, but it is only reflecting it out to your grow area.

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Originally Posted by randyfolds

Glass definitely is not conductive. .................. While that is going on though, you are also filtering out harmful UVB and UVC radiation that is wreaking havoc on your plants DNA.

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Glass definitely is conductive for heat.... it's just a tad slow at doing it. You're probably thinking about electricity, which it can not conduct.

Yeah, glass will block those two kinds of UV light since they're weaker than UVA.... but cannabis produces more resin when exposed to UVB/C just as long as it's not too much to do harm to the plant. Besides, it would only be used for flowering plants that will most likely be killed for harvest. Mothers and clones should be kept safe from it to preserve the DNA.


Anyways, about using a reflector with glass... as long as you got enough ventilation to suck out some of the initial thermal heat produced from the burning bulb, it'll at least keep that extra heat from bothering the plants. But that thermal heat still does transfer through the glass as well as the light which makes heat too. Besides, it's also a good protective covering for the bulb so insects, water, and fast growing plants don't touch it.


But yeah, if you wanna see if it works, just put your hand there at the exhaust coming from the vented hood. If the air feels warm, then you know it's taking away some heat that would have otherwise been left for the regular grow chamber's ventilation to take care of.