Mylar on Greenhouse Walls ? update photos

[Nyboy]

good idea

 

[Circle-M-Farm]

um why not heavy duty aluminium foil... ?

Aluminum foil does a poor job reflecting lumen correctly also it will trap heat causing hot spots. A alternative to Mylar would be a Flat White paint which will reflect 75-85% of light. (Mylar reflect 90-95% of light)

 

[Nyboy]

I tried ordering a roll last night. I filled out all credit card and mailing address info clicked on check out,and ended up on another page. Waiting till later to call them. A roll with shipping was $114. I will hang roll, then decide if I want more.

 

[majorcatfish]

did some reading last night about Mylar, funny thing when i started google Mylar the first couple site where marijuana growing forums. seems the dope growers love the stuff. after reading about Mylar the only drawback is when you clean it gets scratched and over a couple years it will lose it's reflective property. "and yes Mylar does cause hot spots as well".
after reading the dope growers a couple other sites it seems that a great majority say the a good flat white paint is best. once it gets dirty all you have to do is re-paint the walls. $114 buys a lot of paint......

will have to remember this when i build my greenhouse someday...

 

[Nyboy]

wouldn't gloss reflect more light then flat

 

[majorcatfish]

can not answer that one...
since being old school and only use my lights for seed germination only. foil has worked great and cheap for me over the years....

 

[Circle-M-Farm]

Aluminum Foil is no more than 50% reflective.
Gloss Paint is 55-60% reflective
Flat Paint is 75-85% reflective
Elastomeric Paint (Rubber roof coat) 90% reflective
Mylar 90-95% reflective.

The Elastomeric Paints like Kool Seal works great for exposed wood in a Greenhouse. Lasts for a long time.

 

[thistlebloom]

That's good information @Circle-M-Farm . Especially surprising is the rubber roof paint. Never would have even thought of that.

 

[Smart Red]

Thank you, CircleM! Good information as I wait for my basement work to be done.

 

[Circle-M-Farm]

@Nyboy, Here is a small grow box that I made yesterday for starting and growing early winter green and maybe some really early tomatoes. The box is 12x24x16 and only uses two 24" florescent grow lights (the cheep 17 watt ones from Walmart) the material I used on the inside is a Mylar type covering over a foam backer. The reflective light is very good for what lights I used. (My phone camera does no justice to how bright it really is in the box but you get a good idea.)