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Installing Copper Strips Under Shingles

Copper Strips
Installing Copper Strips on a Shingle Roof

Watch this short video first. The column below it was written ten years before I taped the video.

Think of how many people are out there who just had a new roof put on this past year. Not counting the one million new homes built last year I'll bet there were at least three million new asphalt shingle roofs installed on existing homes in the USA.

The sad fact is that the wide majority of those new roofs have no protection against roof algae. The roofers or the homeowners simply are unaware of the problem and unaware that you can buy shingles that have copper coated colored granules.

I hope you are not in this situation. If so, no problem, as there is a way for you to poison those little devils, bacteriologically known as Gloeocapsa magma. We just need to clean your roof and then introduce copper onto your shingles. I know, you may not like the look of a 2 inch copper strip at the top of your roof. However, it will look a whole lot better than the unsightly algae stains!

Clean the Roof First

Common sense should tell you that you need to clean your roof first. That process is described in another article.

Getting the Copper or Zinc

Sheet copper or zinc is usually available at any roofing supply house. These are the places that REAL roofers go to purchase their roofing products.

What is the Best Copper to Install on the Roof?

The best copper is a lightweight version. I happen to sell the best copper roof strips you can get in the USA.

Do NOT confuse these places with the large home center stores sprouting up everywhere! The roofing supply houses sell copper for all kinds of roofing uses. They also sell zinc. Both metals will kill the algae, but I think you should use copper. Zinc has a tendency to produce a grayish film over time, so it may discolor your shingles. Copper should not cause a problem on your roof.

How Many Strips and Where?

That's tough for me to answer without seeing your individual roof. One thing is for sure, you need the strips as high up on the roof as possible, so that the copper coats as many shingles as possible. Depending upon how long your roof is, you may need a strip of copper halfway up the roof as well. Some roofs are big, some small. One strip, across the entire roof, having a 2 inch exposure should protect 14 to 18 feet of roof below it. This photo shows how the strip should look once installed. This strip is near the top of the roof and is tucked under the last fully exposed course of shingles. It is a piece of tin, not copper, and is only 20 inches long. I didn't have a strip of copper in stock at the time I took the photo. I just wanted to show you what it should look like. Your strips will run the entire width of the roof.

Installation of the Strips

Most asphalt shingles are installed so that they have a five inch area of the shingle exposed to the weather. You will also notice that you don't see any visible nails. If you lift up a shingle you should see the nails. They are just above the bottom edge of the shingle you just lifted. This means that you should be able to slide a piece of metal up underneath a shingle and not hit anything for about six inches (five inch exposure plus one inch nail height.)

Copper Strips


Can you see how you should be able to slide a piece of metal up under a shingle for about six inches? At this point, it hits the nails holding that shingle in place.

Your task is simple. Cut long 7 to 8 inch wide strips of copper. Slide them up under the shingles until you hit the nails. Then, every four feet or so, lift a shingle tab and drive a copper nail through the copper strip. When you let the shingle tab back down, it should completely cover the nail. If this doesn't make sense, you had better call a professional roofer. I have seen lots of mistakes by homeowners with good intentions.

Column B374


10 Responses to Installing Copper Strips Under Shingles

  1. We were told it would be a good thing to glue pennies on our roof to inhibit moss. But we can not find out anywhere how to do that. I have been googling how to glue pennies to your roof, etc and it just wants to give me answers for how to make a penny tile floor. Can you help.

  2. Tim - Can I nail your Copper Roof Ridge Roll 12-Inch Wide X 20-Feet Long underneath the 1st course of shingles below the ridge cap? I only have discoloration on 1 side (North) of my roof and I think the strip would look nicer if approximately half of it was nailed underneath the first course of shingles, similar to what you are showing here. As opposed to atop the ridge cap.

    • You can, but I wouldn't. Based on all my research in my http://www.RoofingRipoff.com book, you want all the copper exposed up at the ridge so it extends the life of the shingles by decades.

      Just do a test. take a piece of plastic or aluminum foil and go up and tape it to the ridge. Come down and look at it.

      I'll bet it looks the same as if you put 6 inches exposed up under the cap shingles as you suggest.

      • Tim- Thank you for your reply. I followed your advice and put on top of the roof ridge (it does not look as good, but it's not bad at all).
        Question: The instructions you included did not mention caulking the nail heads. Should I do that, and if so, what kind of caulk is best for copper nails?

          • Tim- Thanks again for your reply. I nailed into extra thick, ridge cap shingles (GAF TImberTex) and I did not normally feel the nails drive into solid roof sheathing (maybe 20% of nails?).
            I did some research and found that 100% silicone sealant and elastomeric polyurethane are supposed to be okay for copper, so I used that on top of my nail heads. I filed it under "little to lose": It was only $7 plus 30 minutes effort.

  3. In 2009 I bought 50 yr GAF-ELK Timberline shingles with "algae resistance". Not sure if they are capping yet but they sure are discoloring in the shadiest sections. I used your bleach in 1 portion and it worked well. Does "algae resistance" mean the shingles have copper or zinc? Could it be the zinc that is discoloring my roof? Is my algae resistance fading over time? If so do you provide detailed instructions with your copper sheets? My roof caps vary from 1" to 1 1/2" thick and I'm not sure how to calculate the best copper nail length.

  4. Tim - we put a new roof on in 2002 with tamko heritage 50 year shingles.
    This past winter we had two different leaks and the last rainstorm another new leak. After the
    recent leak, we decided we are going to put on a new roof. However, after reading your installing copper strips
    Under shingles, should we try this first before the new roof. Our shingles seem to be degranularizing and approximately eight years ago a contractor who installed skylights for us told us our roof shingles seemed to be brittle for their age. I can send a current roof picture if necessary. We are 66 and 65 years of age and thought the roof of 2002 would last our lifetime. This is very disheartening but we do very much appreciate your investigation. We started a warranty claim this past week but only expect $500.00 if anything. Very expensive Planned obsolescence by the industry for the homeowner. If you think we should replace the roof, what shingles would you put on your roof. Please answer ASAP because if you recomend a new roof and not trying the copper strips we would like to do the new roof ASAP before this winter. Thanks.
    Sandra Boyer

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