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Art
Posted on Sunday, October 21, 2001 - 2:55 am:   

Steve,

First the picture is NOT of a 25 year laminate. It may be a 30 or 40 but it is definitely at least a 300 pound shingle and could be heavier.

That is, of course, unless you're adjusting claims for Big Red, then they're ALL 25 year shingles unless the policyholder has the receipt tattooed on his forehead and a sworn affidavit from the supplier of the shingles and the roofer passes a polygraph test.

Second, it is cracked coating as explained in my post below. It is NOT due to some of the old wive's tales and theories listed below either.

The thermal explanation comes closest to being correct and the cold weather contraction/hot weather application theory is as laughable as some of the other theories proposed by various engineering companies with no practical roofing industry experience.

Read the real reason below. It has to do with the elasticity and sometimes the quantity and/or positioning of the sealant.

Art
Art
Posted on Saturday, October 20, 2001 - 11:24 pm:   

Actually, this cracking is caused by shrinkage of the asphalt in the shingle's coating. All asphalt shrinks. The cracks were caused when shrinkage occurred between two permanently affixed points - the fastener and the self-sealant material.

New advances in the sealant material have become more forgiving and now allow most shingles to shrink and pull at the mastic while still not "letting go" or losing their wind uplift resistance. The nail is still immovable. Mastic advances using modified asphalt and complying with U.L. 997 have lessened this particular failure problem.

It is a weathering problem associated with age and can be lopped into the product defect category. It's proximate cause is not due to any covered peril.

Art
John Durham (Johnd)
Posted on Saturday, October 13, 2001 - 5:13 pm:   

This photo is almost exactly like the one in the Composition Roofing edition of the Haage Engineering Book I have. I have seen this stress cracking many times over the years and have even invited the insured and his roofing representative onto the roof to view the stress cracks and compare them to the pictures in the book. I had a roof go to appraisal in St.Paul Minnesota in 1999 with this type of stress cracking and the insured lost the contest. This is caused by the below listed (posts) conditions and is NOT a insured peril.
Wray Decker
Posted on Saturday, October 13, 2001 - 12:27 pm:   

CertainTeed has a brosure entitled "The Life Cycle Of Your Roof".It's about 6 pages.Great info and a real help when trying to explain cracking and other noncovered damage to the insured ,or even worse some roof salesman who doesn't know his tape measure from a shingle.The CertainTeed Tech number is (800)345-1145
Strick
Posted on Saturday, October 13, 2001 - 10:00 am:   

Steve,
Based on information from "old" adjusters and "OLD" Honest roofers, they say and I tend to agree that this is "stress" cracks, now we all can decide what type of "stress" , settling,change of temperature, etc.
but it is not from any know "peril" that the policy will assist policyholder in.
John Turk
Posted on Saturday, October 13, 2001 - 9:11 am:   

Another observation could be a decking problem. Was the plywood installed on a staggered pattern with proper allowance for expansion and contraction? Were clips installed joining the plywood in unsupported areas? Often times when a distinct pattern of cracking is observed it can be associated with the decking/sheathing installation. Thermal cycles do affect this.
On several occasions I have had roof claims alledging hail and/or wind damage to the roofing field, observing cracks to the shingle face which ran from the ridge line down to the gutter line. Inspection of the shingle face did not reveal any consistant evidence which would indicate visible hail or wind damage. Inspection to the underside of the roof decking from the attic cavity revealed a remarkable installation of the 1x4 decking. Not one joint in the decking installation was apparent. To avoid destructive inspection I observed the decking installation from the gutter line, lifting the shingles to find every piece of decking was cut to span the 16" o/c rafters and butted together without any observable allowance for expansion. As a result the expansion and contraction affected the shingle installation. The claim was denied, the insured hired an engineer, performed destructive inspection and came to the same conclusion. Often times we are not afforded access to observe such conditions in which case the company must decide if they will honor the adjusters request for an engineer. By the way the home in this case was built around the late forties when materials were in tight supply. Recycling was used even then when wood from packing crates and pallets were used to create decking material, thus the sizing I found.
Just another angle to consider
John Turk
Posted on Saturday, October 13, 2001 - 9:08 am:   

Another observation could be a decking problem. Was the plywood installed on a staggered pattern with proper allowance for expansion and contraction? Were clips installed joining the plywood in unsupported areas? Often times when a distinct pattern of cracking is observed it can be associated with the decking/sheathing installation. Thermal cycles do affect this.
On several occasions I have had roof claims alledging hail and/or wind damage to the roofing field, observing cracks to the shingle face which ran from the ridge line down to the gutter line. Inspection of the shingle face did not reveal any consistant evidence which would indicate visible hail or wind damage. Inspection to the underside of the roof decking from the attic cavity revealed a remarkable installation of the 1x4 decking. Not one joint in the decking installation was apparent. To avoid destructive inspection I observed the decking installation from the gutter line, lifting the shingles to find every piece of decking was cut to span the 16" o/c rafters and butted together without any observable allowance for expansion. As a result the expansion and contraction affected the shingle installation. The claim was denied, the insured hired an engineer, performed destructive inspection and came to the same conclusion. Often times we are not afforded access to observe such conditions in which case the company must decide if they will honor the adjusters request for an engineer. By the way the home in this case was built around the late forties when materials were in tight supply. Recycling was used even then when wood from packing crates and pallets were used to create decking material, thus the sizing I found.
Just another angle to consider
Chuck Deaton
Posted on Saturday, October 13, 2001 - 8:48 am:   

This just an echo to something Todd said. In 30 years of adjusting and God only knows how many climbed and measured roofs I have only seen this condition 5 or maybe 6 times. Undoubtably more of the roofing I have examined over the years was roofed in hot weather. There is some other factor at work.
JimB
Posted on Saturday, October 13, 2001 - 12:25 am:   

In your post you mention that the product is a 25 year laminated shingle, but you don't mention the age of the installation nor whether it is a fiberglass or organic shingle. Cracking is definitely a mode of failure, however the time of occurance during the life span of the shingle determines if it is a premature or a natural demise. All of the defective shingles I have seen have been fiberglass and the cracking occurs somewhere between 9 and 12 years after installation. Also the cracking is very distinct or obvious runnig either perpendicular or diagonal to the shingle butts. This was a manufacturing problem due to sub-standard fiberglass mat used in the composition of the shingle. The mat is unable to withstand the stress of normal expansion and contraction.

From what I see in the pictures this roof appears to be older, say in the 20 year range. The deterioration appears to be widespread and the horizontal cracking is most prevelent approximately 2" up the tab. This coincides with the top of the head lap of the shingle beneath. The tabs settle into the void created where the shingles lap and there is a ridge of sorts that forms at the transition point. When the asphalt ages it be comes brittle it cannot flex over this transition and thus it cracks. I would bet that the mat beneath the crack is still in tact. If the roof is 20 years old on a southern exposure the roof is simply at the end of its service life regardless if it is a 25 year shingle or not. If it is 15 years in age or less, then it is a premature failure. At any rate shingle warranties are pro-rated and limited to the cost of materials.

It will get worse over time because that is the natural order of things (Except for me. I am getting better every day.).

As for venting you could start a whole new thread on the that subject. Ventilation or lack thereof will neither help nor hurt this roof in any significant way. The primary purpose of ventilaton is to create and air flow over the underside of the roof deck. In colder climates the flow of air prevents the formation of condensation on the wood structure of the roof, thus preventing rot, mildew and the latest environmental hazard "mold". In my opinion it cannot be proven beyond a reasonable doubt that passive ventalation cools the roof deck enough to effect shingle longevityin any significant way.
ToddSummers
Posted on Friday, October 12, 2001 - 11:40 pm:   

This is a very perplexing problem. I have seen it only a few times out of a few thousand roof inspections. Sometimes the cracks are diagonal and vertical as well as horizontal. Some of these roofs were less than 10 years old. The explanation offered by Chuck, Ric, Tom and Haag SEEM like a very logical and plausible accounting for what caused this condition. I am not arguing that they are incorrect. I just wanted to share a line of thought... Wouldn't we all agree that most roofs (more than 50%) are installed when it is "hot" ? That said, why do we see so little of this occurrence ? And why are most of the cracks on the upper 2nd layer (laminate portion) and not on the lower portion that is actually sealed to the adhesive strip. And why are there sometimes vertical cracks. I for one am not convinced that this is not a material defect, regardless of what the engineers say. ( Insert your favorite engineer joke here ).There are obviously many manufacturers who make a product that is (flexible, pliable ?) enough that this does not occur in their products, yes, even though they were installed when it was "hot".

The good news is that as a catastrophe adjuster looking for hail damage on a roof, none of this really matters. There is no coverage whether it is a material defect or not. Hopefully you can find hail damage on these roofs. These cracks are definitely not caused by hail.

The only situation that a determination would be needed, is if there was covered damage caused by leaks coming through these cracks. In this case, determination of manufacturer defect and possible subrogation should be decided by management.

In my opinion, there is a question of possible material defect. Just my opinion... I could be wrong.
Tom Toll (Tom)
Posted on Friday, October 12, 2001 - 3:03 pm:   

Chuck and Ric are correct. I had this type of damage investigated by Haag many years ago. If the shinlgle is nailed down while hot and the seal strip adheres, when, in colder climates, the shingles get cold, they contract. Upon contracting over time, the material separates, causing the shingle to fracture due to the expansion and contraction index. This is not a shingle failure and cannot be placed upon the manufacturer.
Ric Vitiello (Ricvitiello)
Posted on Friday, October 12, 2001 - 1:29 pm:   

From what I can determine from photos only, it appears that this is as Chuck has suggested, a case of thermal cycling damage which occurs over time and at a period in the service life at which the shingles have begun to embrittle from age. This does not mean that it is or is not a manufacturers defect. One thing to note: A good test for this is to determine that the self seal strip on "All" of the cracked shingles was successfully adhered and if you can find any shingles where the self seal failed to adhere, "none" of them are cracked. This will further prove thermal cycling as the cause.

Ric Vitiello, president
Benchmark Services, Inc.
Roofing Consultants
Hail Damage Assessment & Trainers
http://www.benchmark-services.com
Chuck Deaton
Posted on Friday, October 12, 2001 - 12:56 pm:   

My understanding is that this type of condition is caused by the expansion and contraction of the shingle.

I would expect that the shingle was installed in the summer months and was expanded when it was nailed down and the seal tabs adhered. Then over time the shingle expanded and contracted and as time went by and the shingle lost it elastisity it cracked.

I think I have seen this condition illustrated in a Haig & Haig publication.
mark (Olderthendirt)
Posted on Friday, October 12, 2001 - 12:33 pm:   

It is my understanding that it is a manufacturing problem. You didn't say how old the roof was, I have only seen this on roofs 15+ years old. This is likely one we can all agree on, not hail.
JohnTurk
Posted on Friday, October 12, 2001 - 9:51 am:   

Its hail damage,
The old razor shaped hail!
Just kidding.
steve florig
Posted on Thursday, October 11, 2001 - 11:43 pm:   

Here's another question for all of you (sure do have lots of stuff going on down here in the fine state of Texas).
Here we have horizontal cracks in a 25 year laminated shingle. These cracks are all over the roof. My resources indicate that this is a problem caused during the manufacturing process. Does anyone know what exactly happens at the factory that causes this to occur? Does it get worse over time? Will an improperly vented roof make it worse?

And please, don't anyone tell me this is hail damage!

cracks

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