CD/DVD Roofing Concept

Step 7 Longevity

The pictures below show the finished concept board. Since I don't have a shed or a dog house I thought I'd demonstrate the concept and test how it holds out against the elements so that others can use this knowledge to roof if they wish to.

I have some concerns about the ability of CDs and DVDs to hold up against frost and UV. If you'd like to be kept up to date with how they're holding up, please subscribe to me. I will post a forum topic in April once the frosts are over and then again in August after it's been out in the sun all summer.

April Update: (remind me if I haven't posted it by May 2010)

August Update:

Comments

[teenabrayen]

I was looking at this and am trying to think of a way to turn this into a solar panel. Any ideas would be nice.

As well, I was wondering, if you are worried about longevity what about covering this with plexiglass. As this would save from rain getting in the holes or possible weather cracking the cd/dvd. Just an idea to add a bit of life to this wonderful creation.

I am going to try to add a roof of these to my kids playhouse as it is cheaper and makes use of all these old CD/DVDs that are no longer used and had ads and AOL useless information.

[Light_Lab]

Actually you are on a winner; polycarbonate as used to make CD's has excellent weather resistance. Another thing worth mentioning is that CD's are much lighter than concrete or clay tiles. This is an important consideration in earthquake prone areas - I would rather be buried under 20,000 DVD's than 5,000 tiles.

[blago]

the plastic will last, but the foil and printed side will peel and fall to the ground - not sure *at all* if you'd call that eco-friendly. This happened to my home-burned CD-roms that I used as a bird scaring device. Worked pretty good, but they lasted just one summer!

[xenor]

The polycarbonate is quite durable, but I'm not sure how the thin layer of lacquer on the label side would survive.

[robosilo]

Looks like a good use for laser discs!!!!!

[jeff-o]

Hah, good luck collecting more than a handful of them, though.

[thalden]

I have no idea how CDs would hold up in a situation like this, but I have found my share of discs "in the wild." What I've found is that the label, and often the metallic foil side as well, peel away after much, much time in the element. The clear polycarbonate disc may yellow some, but it remains strong and won't actively break unless something lands on it, or it gets run over.

One problem I can see with this design is if ice dams form in the gutter, the ice could back up the roof and wedge its way under the CDs, loosening or even cracking them. Also, not having a sealing layer of tar paper or something similar could lead to moisture seeping in and rotting your wood.

[tonyi]

Excelent use of old CD's & DVD's. i can see it now on my hen house & kennel.

You can double up on your old cd collection, what i did discover with my old DVD's is ... when put them in boiling water it starts to split & separate the 2 layers so you end up with 2 thinner CDs, but you loses the nice iridescent shinny side.

[Shiftlock]

Question - What is one supposed to do at the apex of a peaked roof?  Hmmmm... Maybe you could use cut up 2-liter plastic soda bottles for this part?  You could cut them into rectangles, and drape/bend the plastic over the peak of the roof, then nail it down.  Any other ideas for this part?

Comment - I love the idea that you are standing under and protected by a layer of data.  Terabytes of protection from the elements overhead! <okay, maybe that was totally geeky, but it's neat to me anyhow>

[projectbronco]

For the peak, I would get the black corrugated pipe. The stuff that is usually put on the end of downspouts. Cut it in half and use the halved pieces as the roof cap. Then on the end of the peaks, you could fasten a CD to close the ends of the pipe and use caulking to fill any cracks.

[Shiftlock]

That's a very good idea, but I was hoping to come up with an idea using some type of recycled material, just to continue the recycling theme.

[maven]

Soda bottles would break down too fast. 
In Tx, I have trouble with 5 gallon buckets (both the square cat litter buckets and the regular drywall compound style buckets I use for feed storage and waterers) breaking down from the UV in less than 2 years.  I will be extremely interested to see how the CDs fare after a summer.

[Shiftlock]

Most 5-gallon buckets are made of HDPE (high density polyethylene), which breaks down a lot faster than PETE (polyethylene terephthalate), which is what soda bottles and CDs are made of.  Even a thin sheet of PETE, like that in a soda bottle, will last much longer when exposed to UV and temperature fluctuations than a thick HDPE container, which will lose it's tensile strength, become brittle, and crack over time (this is probably the failure mechanism you're seeing in the buckets you're using).  People have made boats out of used PETE soda bottles and sailed across the Pacific ocean.  They will certainly last a very long time on a roof, as will the CDs.

If you want buckets that last a long time outdoors, try to find some made of PP (polypropylene).  This is the material that Tupperware containers are made of, and it will last a lot longer than the HDPE buckets you've been using.

The moral is this:  Not all plastics are created equal.

[Light_Lab]

Actually Shiftlock seems to have it backwards;  People often relate the urban myth that PP is UV resistant based on the use of PP for garden furniture. I am sad to say I was involved in R&D when that started and I know that PP was selected to ensure more sales; a product with a deliberately limited lifetime. Of all the non-aromatic common polymers unstabilized PP stands up the shortest time in UV.
Polymers that contain aromatic groups usually resist UV very poorly and that includes PET. In this lab we have studied PET water bottles that were left in the sun for less than 12 months and they have gone yellowish and brittle as egg shells.
We did have a project once to make PET surf rescue boats but it was dropped partially because of the long term UV exposure concerns.
HDPE, particularly when UV stabilized, has some UV resistance and is often used for marine components.
Really though the only common place polymers that stand up to UV are acrylics and polycarbonate; most other polymers are UV stabilized to some degree  depending on their expected UV exposure.
BTW most CD's and DVD's are made from polycarbonate and thus have excellent UV resistance. Often though the clear packing disks seen in 50's boxes are just polystyrene ie not UV resistant.
If it was me I would cap with PVC angle - like they use for PVC down pipes - full of white filler to block UV and I would probably paint it to make doubly sure.

[GEOD998]

if we are going to use store bought materials for a ridge cap-why not just use  ridge vent that is cheap,some have high% of PCRMs, made of plastic,and helps cool the roof surface-which can only help the lifespan of the CD/DVD roof? If we're going to paint,the ridgecap,why not use an automotive grade paint on the whole roof? -it is UV resistant-Just my two cents ,take no offense-Jayefuu-nice use of stuff that would have ended up in a landfill. BTW- I have warmed these with a heat gun and used a bolt thru the center hole to pull these into tiny parabolas-they do work-and with a coat of clear automotive urethane-based paint,they seem to have held up very well-I'm gonna have to go back to that project now that I've seen this-just what I needed,another project,thanks alot Jayefuu-lol

[Jayefuu]

Thanks :) Post photos if you roof anything with this, I'd really like to add them to the instructable.

[GEOD998]

Jayefuu-most of what I've done with DVD/CDs is for solar concentrators,but I do construction and roofing (among other things) in my business. A few ideas from my construction experiences-if you were doing a large area,a roofing nail gun with a foot attachment for vinyl/alum/cementitious siding could be helpful.The attachment is adjustable and stops the nail from going all the way in.This is used for vinyl siding so it can "float"-allowing for expansion and contraction-when you see siding that has buckles in it during the summer,its usually because the contractor didn't have one of these,or if they hand nailed they drove the nails down tight.But anyway,many rental stores have them to rent for a day,some will even give a 4 hour rate!  With that little tool you could rock n roll,just like asphalt shingling a roof without worrying about cracking the CDs.Also,using a heated rod to make the holes may reduce any tendency to crack or "run",I've done that when making holes in siding.When it's all said and done,Kudos to you-Its your great Idea-i'm just one of those guys that stand back and say"you shoulda/coulda done this or that"-lol.sorry,I hate when people do that to me,but in this case ,its done with the best intentions

[Jayefuu]

I've had success with soldering the CDs together. An old soldering iron works well, poking it through to attach CDs. I'm going to build a plastic bender jig, bend the CDs then solder them together with another layer either side of the apex. I'll probably update this ible then post a forum topic to notify my subscribers I've updated it when I do.

[EmmettO]

 A heat gun might work well for bending them if you have one. It's like a hair dryer on steroids.

[Jayefuu]

I do have one, but think it would heat unevenly; I wouldn't get a sharp and consistent bend. I'm thinking... nichrome wire with a current to heat it up, position several CDs over it then pull a handle to bend them 90 degrees and hold them there. Or just heat them up in a line across the middle and then put them on another jig until they cool.

[tonyi]

Let me know how you go bending them. i tried to bend CD's with heat but it failed.
what i did discover is ... when put them in boiling water it starts to splits the 2 layers so you end up with 2 thinner CDs, but you loses the nice iridescent shinny side. This thinner layer may be better to bend without cracking & breaking them.

[miles-fisher]

Great idea, I will give it a go. I will look forward to reading the weather updates. Personally I cannot see any problems other than driven rain penetrating between the discs.

[Jayefuu]

Thanks. Please post pictures if you have any success :) Would love to include them in the ible.

[jartrimmer]

You need to lap the cd's a little tighter together. If you have a blowing rain the center hole will leak.