I thought this was an interesting question. IÂll post some thoughts in the hopes it will spark comments from others. I found one thread that mentions frosted glass being used in a conservatory: Opinions on Frosted Glass? Frosted glass does diffuse the light, and diffused light is beneficial. In spite of that, I couldnÂt find much information on the Internet regarding the use of frosted or etched glass in greenhouses. So, my guess (just a guess) is that frosted or etched glass is not widely discussed as an option for glass greenhouses because it doesnÂt negate the need for shadecloth or whitewash in sunny situations. If it provided a definite advantage over clear glass, it seems like it would be easier to find more references to its use. I donÂt see why it would be too opaque. Maybe itÂs not discussed much because the people who choose glass greenhouses also enjoy seeing in or out; if they didnÂt care about that, they might as well choose polycarbonate. That being said, I think you have a good reason to work with this idea. If it helps you transform recycled windows into something that pleases you when you look up at themÂinstead of being annoyed by streaksÂthen why not? The only downside I can see is you might find you still have to do something additional to diffuse the sun coming into your structure. (I wish I had the experience to wager a guess about that, but I sure donÂt.) IÂd be tempted to try one window (or a scrap piece of glass) to see if I liked the results. Now, if itÂs a double paned window, and you frosted both pieces of glassÂwould that diffuse the light even more? I donÂt know... Maybe someone that knows more about light diffusion than I do will pipe in here.

Well, I got a glass 1 from nursery & no birds came as ports didn't have flowers around them, That part was plastic & I used Patio paint & put yellow flowers around each hole so hole was center of flower. That worked well. Glass part had some red on it so I didn't do anything. But I took a class in glass painting & the paints can be gotten at Joanne's or Michaels. FolkArt Enamels have an "E" on top of the 2 oz bottles,actually by Plaid. But you either have to put glass in oven for couple of hours or let the glass set for 30 days so it is permanent. Go to Plaid website & I think they would tell you how long the glass would have to be in oven. I made a mug decorated with roses for hot tea so just let it sit 30 days. Think when you turn oven off you just let it sit overnight until cool & then can use next day.www.plaidonline.com is their site & I think would locate store near you also. Jan

Have you thought of using the stain glass paints? You could change them up again later if you wanted to because the product is not permanent. Here is a website that sells it. http://www.plaidonline.com/apGG.asp Or you could use a permanent paint like Delta's Permenamel. http://www.deltacrafts.com/Paint/PermEnamel/ Here is a link that might be useful: Gallery Glass

If you go to the bottom of the page there is a search box for this fourm, if you type in glass blocks quite a few post will come up and I am sure you will find alot of info! you can also go to the craft fourm and do a search ,theres alot of beautiful photos of glass blocks to inspire you, some people use decals, some printed graphic, and of course hand painting, hope this helps, come back and show us your finished blocks. almost forgot to say you can use a extender with acrylics paints for a transparent look, gives the look of stained glass. oddie