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Cellophane strip found on / between asphalt roof shingles: this article describes the cellophane strips found between individual asphalt roof shingles - atop the glue strip.
We explain the purpose of this cellophane strip. We answer the question: " Should we remove the cellophane strip when nailing shingles or should it be left in place?" We cite authoritative research from industry experts as well as from shingle manufacturers themselves to give a definitive answer to the asphalt shingle release strip removal question: leave it in place.
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What is the Purpose of the Cellophane Strip on Asphalt Shingles?
The cellophane strip, found between individual asphalt roof shingles and located just over the glue strip that bonds shingles together is factory-installed to prevent shingles from sticking together while they are still in the bundle - in storage.
The success with which asphalt shingles bond together as the glue strip is heated by sun exposure is a factor in protecting roof shingles from wind-damage and blow-off.
Should we Remove the Cellophane Strip when Installing Shingles? Bottom line: NO!
The debate about whether or not a protective cellophane strip found atop this glue strip on new asphalt shingles has gone on for years and comes up again as new roofers enter the field. Do we remove the cellophane from the shingles as we place them on the roof for nailing or or do we leave it in place? Does it matter one way or the other?
No: In answer to a common reader question, not normally: according to roofing manufacturers, it is not required to remove the cellophane strip on the back of roof shingles before they are nailed. Below we quote from a major manufacturer's instructions.
In short, the people who make shingles tell us to leave the plastic or cellophane sealant protectgion strip in place, explaining that when the shingles are nailed in place the strip on the successive shingle course will no longer be in contact with the adhesive sealant strip on the upper surface of the lower or previous shingle course. [There may be other shingle products in which the strip dissolves, but the strip offset explanation is unambiguous - Ed.]
Yes: as we discuss in more detail below, experts familiar with wind damaged roofs (in coastal areas exposed to hurricanes and in other high-wind areas) previously recommended both the removal of the cellophane strip and the installation of double-sticky-sided roofing adhesive mastic tape or roof cement under shingle tabs at the time of asphalt roof shingle installation.
We agree that adding sealant may be appropriate for some shingle products in some wind zones or weather conditions and may even follow the manufacturers' instructions.
But you don't need to remove the protective stripon the under-side of an asphalt shiingle just to add sealant.
Watch out: furthermore, for some shingles or brands we have observed that tearing off a release strip that happens to have strongly bonded to a shingle can sometimes pull off part of the shingle back, damaging the product and shortening its life.
As Cramer reported in 2009 (see "More on the "yes" answer" just below, currently asphalt shingles sold in high wind areas adhere and cannot be pulled apart by wind (nor hand) once they have set on the roof.
What is the Purpose of the Glue Strip on Asphalt Roof Shingles?
Prevent shingle damage from wind uplift
This asphalt shingle adhesive strip is intended to bond to the three tabs of the next shingles nailed atop of this one when the roof is later warmed by sunlight.
On occasions, particularly during high wind conditions such as hurricanes, defective glue strips or adhesive strips on the underside of asphalt shingles may not provide sufficient adhesion, or if the shingles were not properly handled and the glue strip was dirty, an adhesion failure can lead to failure of the shingle tabs to adhere to the nailed-down header of the shingle above.
In this case exposure to high winds can cause shingles to tear or blow off of the roof, increasing the degree of water damage inside the building when such winds are accompanied by rain.
In most climates exposure to even a few weeks of normal sunlight will cause the glue tabs on the under-side of asphalt roof shingles to soften and adhere to the surface below.
We discuss the function of asphalt shingle adhesive strips, handling the protective cellophane strip, and shingle uplift wind damage prevention in more detail at WIND DAMAGE to ROOFS.
Certainly if you wait to remove the protective cellophane strip until the moment that the shingle is about to be nailed, taking it off might do no harm, but because it is nowhere near the actual glue tabs or strip of the shingle course below, removing the release strip will not speed the adhesion between shingles that is intended to resist wind blow-off of roof shingles. We suspect that few professional roofers will add to their roofing time and cost by taking a step that is not recommended by the product manufacturer.
And as we cite elsewhere in this article, in some cases pulling off the release strip can damage the underside of the upper shingle course being nailed.
Roofing Manufacturer's Advice about the Cellophane Strip on Shingles: leave in place
At ASPHALT SHINGLE INSTALLATION we include this quote from the GAF Materials Corporation, Grand Timberline™ Premium Architectural Shingle Application Instructions say about the glue strips and cellophane.
You'll note that according to the manufacturer we are to leave the cellophane strip in place, but if site conditions (high wind) require immediate shingle sealing, an extra step, using additional shingle tab adhesive, is permitted. [Italics ours.]
Our photo at left illustrates the "Miami-Dade County Approved" imprint found on the underside of an asphalt shingle that meets Florida's wind-resistance requirements.
In the warning just above the company is referring to the use of additional roof shingle adhesive, not the factory-applied glue strip. Also see BLISTERS on ASPHALT SHINGLES.
The film strips on the back of each shingle are to prevent sticking together of the shingles while in the bundle and to keep dirt and debris out of the adhesive material so that after installation the adhesive will work. Their removal is NOT required during application.
More on the "no" answer to removing roof shingle cellophane strips
Our photograph of the cellophane strip in place on the underside of an asphalt roof shingle (left) clearly shows that the shingle manufacturer says "Do Not Remove This Tape".
The cellophane tape on the back side of asphalt roof shingles is intended to prevent the glue strips from becoming activated prematurely, in storage or shipping, and equally important, to keep the glue-area clean during the roof installation process: jobsite debris (sawdust, dirt) can prevent the sealant from adhering.
What more can we say: the under-side of the asphalt shingle shown at left plainly says "DO NOT REMOVE THIS TAPE"
[Click to enlarge any image]
Once the roof is installed the heat from sunlight will activate the sealing mastic through the cellophane. It does not need to be removed as part of the roofing process.
Actually, trying to remove the strip after installation might also risk damaging the shingle since you'd have to run along the roof slope lifting nailed-down shingle tabs to try to (unnecessarily) pull off the cellophane - risking tearing shingles and causing also extra foot traffic wear. Indeed a few times we have seen actual pits and holes in the backs of shingles when a roofer ripped off the cellophane that was very bonded to the shingle surface.
More attempts at the "yes" answer on removing roof shingle cellophane strips
One of our readers, Leonard Wheeler, reported that independent analysis of wind damaged roofs concluded that "... many shingles and attachment adhesives used were not adequate for the wind speeds that occurred. The most common failure mode was lifting of the tabs due to failure of the self-seal adhesive, and subsequent tearing of the shingles at the fasteners (Smith, 1994)."
However, because the release strip is nowhere near the glue strip of the shingle course below, the release strip in place will have nothing to do with whether or not the shingle seals adequately from sunlight and heat on the roof. Rather, if more wind uplift resistance is needed, extra adhesive might be added during roof installation.
Our associate, Mark Cramer, a Florida home inspector and educator in the field, reported that houses suffering damage during Hurricane Andrew were generally those not built to code, and that code-built homes survived the hurricane with minimal damage. Mr. Cramer provides this update:
Other measures to reduce water damage to buildings in coastal or high wind areas include use of roof flashing tape or strips of ice-and-water-shield type products over the butt joints between sections of plywood or OSB roof decking. The presence of roofing felt under shingles won't prevent roof leaks after shingles are installed, since the shingle nails will have made thousands of penetrations in that membrane.
A Forensic Engineer's View on Cellophane Strips on Asphalt Roof Shingles
I am a forensic engineer who works for insurance companies. Occasionally I find a limited number of shingles on a roof did not seal because the cellophane strips have attached to the seal strips instead of staying on the underside of the shingles in the package. Let me try to explain that better.
The cellophane strips are attached to the center of the undersides of the shingles at the factory. The seal strips are on the top side at the center of the shingles.
The only time the cellophane strip protects the seal strips is while they are still in the package. Occasionally stacks of shingles are left out in the sun before they are installed, sometimes while at the distribution center, sometimes at the factory, sometimes on the truck that delivers them, sometimes in stacks in the yard before they are installed, and even sometimes across the roof before the roofers open the packages.
In those cases (you see above they can be many cases), the solar radiation can activate the sealing strip adhesive on the top shingle or two or maybe even three, and the cellophane attaches to the top side of the shingle covering the adhesive when the shingles are taken out of the bundle.
Most of the cellophane strips have the instructions not to remove printed on the surface. However, it will be printed in reverse when it sticks to the seal strip (since it is intended to be read from the bottom). However, to most of us that read English it still admonishes that it not be removed, even if it is printed backwards.
With the cellophane in place covering the sealant, the shingles installed over those individual two or three (per bundle) will never seal. This leads to blow-off failure more often than you would think.
I find several like this every year and there may be as many as ten to 15 complete missing shingles on a single roof because of the cellophane sticking to the seal strips.
That is usually enough to put the insurance company on the hook for an entire roof that somebody installed incorrectly.
- James A. Skees, PE 
Opinion on When to Remove Cellophane Strips on Asphalt Shingles -DF
Based on the above our opinion is that you may and should leave the cellophane strips in place on the shingle back surface (which is ok with the manufacturer) so long as the strip is intact and in its original position.
But when installing an asphalt shingle roof if you encounter cellophane strips that have already come loose, you may as well remove them and dispose of them off of the roof. The roof will look like a junky installation if there are inches of cellophane blowing in the breeze all over the new roof.
Watch out: Do not leave loose cellophane strips nor any other extraneous debris on a roof, especially when installing new roof shingles as those materials may interfere with proper roof tab sealing and may lead to future increased shingle blow-off in windy conditions.
About deliberately pulling off all of the tabs: if you are in a high wind area and are going to be adding additional sealant anyway, this step is probably unnecessary and is not specified by the manufacturer.
Earlier, in the 1990's we were concerned with excessive bonding between shingles that combined with a lack of tear resistance to lead to premature roof failures due to thermal splitting. It's fair to add, however, that the root cause of that problem was a specification that led to inadequate tear resistance, not an innate fault with shingle tab bonding.
Reader Question: so what happens to the plastic or cellophane strip? If we knew we might stop arguing about whether to remove the strip from shingles or not
[In the article above] you really should include an explanation from someone about what happens to the cellophane strip in the normal adhesion process. Does it break down and allow direct contact? Does it react with the sealant allowing the sealant to pass through?
Does the sealant simply flow around the strip to achieve adhesion? A proper understanding of any process is key to once-and-for-all removing doubt as to the correct interpretation of a procedure. Someone must know how this works. - D.C. 6/13/2013
Reply: the sealant protection strip is offset from the adhesive strip when the shingles are nailed in place - they no longer touch: leave the sealant strip in place
I certainly appreciate your comment and agree that your question is one that many people ponder. I thought we'd driven the nail in the coffin of this debate by citing the manufacturer's advice above, but your comment is a reminder that we never explained just what happens to the cellophane or "plastic" strip - if anything does happen for that matter.
The company explains that the plastic sealant protection strip is not biodegradable, does not dissolve, melt or anything else. [We add that this means if you could pull off these strips, against the instructions of the manufacturer, you're creating a mess of stuff blowing all over the site: debris that does not magically disappear on its own.
The placement of the asphalt shingle sealant protection strip is the key.
GAF explains that when shingles are in the bundle the plastic (or "cellophane") strip on the underside of a shingle surface is positioned so that it prevents sticking of that shingle to the self-sealing adhesive on the upper surface of the shingle beneath.
But when the roof shingles are installed according to specifications, the location of successive shingle courses will make sure that the stick-preventing plastic strip (bonded to the underside of a shingle) will be offset from the actual location of the sealing adhesive of the shingle course below.
You can see this by noticing where the adhesive strips are in an installed asphalt shingle roof in our illustration (above left).
On the topmost shingle in our illustration, the cellophane strip on that shingle would be on the shingle underside exactly the same distance from the shingle top as is the adhesive strip on that shingle - placing the strip a good 4-inches above the adhesive strip on the course below.
Here is how GAF explains the release strip found between asphalt roofing shingles:
So there is no need to remove the plastic/cellophane strip and further, it should not be removed. Why not? Well in some cases tearing off the strip may remove shingle material, thus damaging the shingle and reducing its life.
In any event, the guideline on leaving the strip in place is clear and unequivocal. Let's hope that with GAF's help we've driven a nail into this popular roofing legend. GAF Technical services can be contacted online or by telephone as we cite in our references below.
Reader Question: determine shingle age from presence of paper-type shingle release strips?
8/19/2014 Matt S said:
I was inspecting a roof the other day, and I found that the strip was made with a paper product (not plastic or cellophane). The roof appeared to be old; however I am unable to verify due to lack of knowledge of the homeowner and the lack of building permits. Would the paper strip help to speak to the age of the shingle? In other words, was there a time when they transitioned from paper to cellophane? Thanks.
Matt that's a very interesting observation. I've installed a few roofs, dating back more than 20 years, without encountering a paper release strip for the adhesive tabs - so the variation may be as much by brand as by age.
These patent disclosures refer to paper release strips on asphalt shingle adhesive spots. The description typically is a silicone-treated paper rather than cellophane.
You'll see the years span quite a range, at least from 1988 through 2004. I *suspect* that the reason we see more cellophane than silicone-treated paper release strips is that should a segment of cellophane escape and show on the finished roof it will break down more quickly and be less visible than its paper cousin.
Continue reading at WIND DAMAGE to ROOFS or select a topic from the More Reading links shown below.
Suggested citation for this web page
Frequently Asked Questions (FAQs)
Question: why are there glue strips or spots on asphalt shingles ?
(Apr 2, 2014) Pat said:
I have installed the shingles on my house and removed the cellophane and in the 20 years since then I have not lost one shingle. I moved to a senior housing development and the roofs here are 14 years old and low and behold we had a wind storm and shingles are all over the place along with the cellophane and now a contractor is going to try to sell us to replace all the houses that were not damaged to get new roofs. What ever happened to 20 or 25 year shingles?
Why put the glue strips in the first place?
Pat, the glue strips are there to allow the single taps of each upper course to bond to the lower course (with a bit of time and heat from the sun). This bonding in turn prevents wind-damage that otherwise lifts the shingle tabs and blows them off of the roof.
The people with the most at stake in this argument are the roofing manufacturers- we should follow their advice.
Leave the cellophane or paper release strip in place; it's not interfering with bonding, it's job is to prevent the shingles from sticking together while still in the bundle. When the shingles are installed in offset courses up the roof the release strip stuck to the under-side of an individual roof shingle is no longer covering the wind-uplift-damage-prevention glue spots or strips that are exposed on the upper surface of the shingle in the course below.
This is of course a separate question from your last sentence.
Question: reader finds experts confirm: leave the release strips in place but still disagrees
(June 20, 2014) Mike O said:
I called the Roofers Union and they backed up the contractor and said leave the cellophane on.
I have had my roof since 1999 and only 5 shingles blew off and they were the 5 shingles that still
Mike, we have researched this question with great care to find and cite authoritative sources and to put the arm waving speculation. The article above gives correct information. Please take another look and let me know if anything you see there is unclear.
Question: reader doesn't understand that staggered shingle courses eliminate release-strip worries
(June 21, 2014) Anonymous said:
Try this simple logic: The manufacturer wouldn't have put the goo on the shingle unless it was going to be used to stick to another shingle. Obviously the cellophane strip is to keep it from sticking to other shingles while in transit. The only unanswered question is: Does the cellophane dissolve swiftly after installed, presumably due to the heat of the sun? If yes,the goo would be allowed to serve its purpose - eventually. How long or what minimum heat does it take to dissolve the cellophane? If the cellophane does not dissolve, the goo was put on for no reason whatsoever. If it does dissolve, removing the cellophane manually allows quicker sealing of the goo to the underlying shingle. In not taking the time to remove the cellophane on installation, the installer is gambling that a high wind won't occur before the tape dissolves. I presume also that, if the cellophane is removed, it opens up a lot of opportunities to touch down the shingle a bit crooked, probably without the ability to lift it back up and straighten it. That is another cost factor - lost time and damaged shingles.
Simple but mistaken logic. Please read the article above. You'll see that at installation the self-adhesive tar strips and the cellophane strips remain nowhere near one another once the shingles are installed - see the arrows on our illustration, and also that forced tearing off of the cellophane is not recommended by the manufacturer, in part because doing so can cause shingle damage.
Question: reader questions why there is sticky stuff on the underside of the shingle
(July 30, 2014) pete ianuzzi said:
so why is there sticky stuff on the bottom, just to hold the cellophane tape in place?? and did mfr.'s original require you to remove this seal. I seem to remember reading that in the small print many years ago...40+years ago
of course not Pete
The functional sticky stuff is the sealant that is present on the upper surface of the shingle in the course below. That sealant is heated by the sun, sealing the next upper course shingle tabs down on to the lower course of shingles.
A small amount of adhesive between the release strip (cellophane or silicone impregnated paper strips) holds the release strip in place bonded out of the way to the underside of the next upper course of shingles. It's not in the way and should be left in place.
Question: reader doesn't understand glue strips, shingle course offset, and does not agree with instructions from the shingle manufacturer
(Aug 8, 2014) Anonymous said:
I just read an article at Inspectapedia.com/roof/shingle....Anonymous below is correct!!!!! Although they go on to
ROOFERS don't want to remove it because of 2 reasons....it takes too long AND if your working like a mad man
ITS ALL ABOUT THE $
One simply cannot imagine any economic benefit to roofing shingle manufacturers that would accrue from your argument.
But you are part of a considerable group of folks who have trouble picturing where the release strip ends up and where the actual glue strips or spots end up as shingles are placed on the roof. Check out the photo with arrows in the article above and you'll see why leaving the release strip alone is harmless and is recommended.
I should add that in a few instances we have actually seen shingles damaged by the pulling off of the cellophane strip.
Bottom line: remember that the manufacturers have a lot at stake in the successful installation and life of their product. While there may be some arguable compromises on product quality, life, warranty and other worries, following the roof shingle manufacturer's own instructions on how their product should be installed is the smartest approach to roofing.
It is unfortunate that so many people are confused about the cellophane strips and roof shingle tab sealant, particularly as the manufacturers and other experts have written so clearly on the matter. What we have published on this matter is hardly personal opinion. It's researched and cites authorities on the topic.
You are mistaken in your "all about money" claim in this case - the manufacturers don't make any more money with or without cellophane strip removal, but they do know what leads to product success or product failure - which is of great import, and which is why shingle tab sealant is provided in the first place - to protect against wind uplift.
It would appear that your confusion and that of some other readers stems from failure to notice that when shingles are taken out of a bundle (in which the cellophane on an upper shingle's underside prevents it from adhering to the adhesive tabs on the upper surface of a shingle below), and then placed onto the roof in successive courses, the underside of the upper shingle is a good 4-6 inches higher up-roof (depending on the shingle exposure) than the tab adhesive spots of the shingle below.
Thus the cellophane, left in place as the shingles are installed, is now here near the sealant tabs so it can not interfere with shingle adhesion.
Take a look at the annotated photograph just above in this article and you can see that shingle layout.
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