I have always heard foil and really reflective surfaces in grow rooms are a bad idea, so i decided to put plain white paper on the walls for reflection. For my 2nd grow however i want to paint the walls white as it is easier to clean.

Would you agree matt white paint is better instead of gloss paint?

I dont want a shiny surface as i fear it would do the same as foil and cause hotspots.

Do the walls around your grow help to reflect light?

Thank you for the help, jp

The albedo (fraction of the light reflected) of white paint is about the same for gloss and matt; about 0.5-0.9 depending on the quality. Lots of interest in this at the moment as painting roofs white might help global warming by reflecting light back into space. Oops...off topic.

Anyway, the main difference is that gloss paint gives specular reflection whereas matt paint gives diffuse reflection. I don't think the specular effect on a flat wall is strong enough to make hot spots, unlike ally foil which has creases that can cause hot-spots (although the albedo is 0.85). However, a matt finish will give you a more even light distribution.

Do walls help? I reckon so, as they get light to the underside of the plant.

I bought some mylar for my drobe and I swear by it. After installing it I noticed a big difference in the amount of light reflected back. It's also known for being very flat and very cool which it is in mine.

My opinion's not exactly unbiased though, I've only ever had plain wood walls and then the mylar. But you'd be hard pressed to find a more reflective material.

Matt white paint is almost as good as mylar and you can give it another coat every grow. Also police seem to make a big thing over expert set ups ,paint looks less professional.
joe

if you are going to use paint.
and iirc....matt white emulsion paint is the best type to use, it as something around 79% reflectability.

Thank you for all the feedback.I was going to paint it with matt however... decided to put paper up on the walls with sticky back ....

because my boyfriend thinks if we paint the walls then the chemicals from the paint will create a "toxic box of death..." i'm not sure how true this is but the matt paint does have alot of chemicals in and says "keep away from aquatic life"... so i suppose it is best to keep it away from something i'll be inhaling myself..

Is this factor an issue for anyone else?

Hi j'mapplepot

Dulux make a highly reflective paint called Light & Shade with 'Lumatek" technology, whatever that is?

It comes in satin white.

I did use this but first I painted with 2 coats of International 3 in 1, which is a sealer, primer and undercoat.

Hope this is of use, good luck with the grow - metalbasher.

Is spot on, flat white emulsion is excellent........ +also about making your grow look more Homebrewed, less Starship Enterprise, in case you have a bust.

Also think about breathing behind plastics, you do not want areas of trapped cool air and certainly want nowhere with any mould or dankness going on.. it very easily gets into the buds.



The chemicals in gloss paint would probably harm plants drying in an unventilated room, i doubt emulsion would, or that it will be in an unventilated room.

Hey dont mean to interupt just a quick question about the same stuff etc

There is a 500ml (half a metre) space between the walls where the reflective sheeting will be and my plants, im debating whether the diamond mylar (thick stuff) will be worth wile or maybe just black and white if the light intensity breaks up by that space etc etc. What use think?

How reflective is the diamond mylar compared to standard black white