Litre of light project in a Canadian roof

After watching the video from “A Litre of Light”, I decided to try this in my roof of my shed as I had to reshingle it this summer anyway. Here is how it happened:

  1. Make a hole in the really old planks on the roof. I knocked out a knot and used a the rasp shown to make the hole the right size.
  2. Make a hole in the plywood layer on top of the planks. I used a hammer and chisel to make the two semicircles.
  3. Get a piece of aluminum flashing. Use tin snips to cut out out a circle/shape like this. The aluminum is thin enough that you can do minor bending and even rip it with your fingers.
  4. Here the flashing has been put into the roof with the asphalt shingles overlapping the top. The bottle has been inserted and caulking applied.
  5. We now have a problem. In the tropics they just put in water plus two tablespoons of bleach. The problem in Canada is that it will freeze in winter and freezing water expands. I am squeezing the bottle slightly as I fill it so that it has room to expand. I had a couple of ideas to lower the freezing point of the water:
    • add some rubbing alcohol. Problem: bleach (sodium hypochlorite will react with alcohols to oxidize them. I don’t know what strange things would happen.
    • add some salt. This is a much better idea since sodium chloride and sodium hypochlorite won’t react. Salt is also commonly used to lower freezing point of water on icy roads in winter, and salty oceans don’t freeze.
    • Problem: some additive in the table salt makes the water cloudy. You can clearly see this in the photo above. I had to siphon the bleach/salt solution and rinse out the bottle.
    • Final solution (pun intended!): I happen to have 500 mL of salt water from the Dead Sea that’s in my basement for a few years. Nothing grows in the Dead Sea, so I don’t need to add bleach to prevent algae. Unfortunately I need to add almost 500 mL of tap water. I hope that this doesn’t dilute it too much.

  6. Here is a photo of the bottle with its now clear Dead Sea water. Because the bottle cap will deteriorate due to UV rays, you must cover it with something. I have temporarily put black tape over it.
  7. Here’s a photo of the inside of the shed — using a flash.
  8. Illumination of the shed – one setting on a camera.
  9. Illumination of shed – different setting on camera

Summary: You can light up a shed with a “litre of light”. It works, it’s not amazing, buit it does work. (Use Dead Sea water if you can.) However, I don’t think it is really worth it. The amount of light produced is not really worth the trouble. Just get another light bulb. (This shed has a window so that also makes it lighter inside than a dark shanty.) Or, you could get a commercial one: SolaTube.