Roof Inspection-Lifting Shingles-Missing Aggregate-Alligatoring

On a recent Pre-Purchase Home inspection in Ormond Beach we came across a roof that had examples of most of the possible concerns during a home roof inspection. I thought I would take the opportunity to share this for the educational benefit of home buyers. While I have and use infrared cameras it has become a common practice among home inspectors to assume that the use of such equipment negates the need to actually crawl inside the attic. This article will show why it is still necessary to do the crawl no matter how hot and uncomfortable it is. In this one roof inspection-lifting shingles-missing aggregate-alligatoring and broken shingles were found. Along with severe wood rot that did not show up with the use of an infrared camera.


Infrared camera did not pick this up. I have on more than one occasion been called out to a home a month after the purchase to find and document damage of this nature that the previous home inspector did not find. “He had all kinds of infrared cameras and moisture detectors and the inspector said he did not need to go into the attic” is what the new home owner will typically say. If I can get into the attic safely then I need to crawl the attic. The reason the infrared did not “see” this is because it was dry. No moisture means no evaporative cooling thus no temperature differential for the camera to detect. Sometimes the infrared won’t even pick it up when it is still wet if there is no airflow to create evaporative cooling and a temperature drop. Luckily I did not walk across this roof prior to looking in the attic… it was bad enough that I might have fallen through.




Lifting shingles are one of the first things I look for when I get on the roof. A roof can look to be in perfect condition from the ground. The test for lifting shingles is very simple. Use your finger to see if you can lift up a tab as you see in the photo here. A tab like this will flap in the wind of even a moderate storm. It will break off and in the process leave the next shingle tab vulnerable. The tabs then start breaking off like dominos. If there are only a few lifting and the shingles are not yet dried out and brittle from age they can be adhered back down with the proper roofing cement. This will often allow the roof to last several more years.





Notice in this picture to the left how the aggregate is washed away. This could simply be because of the roof covering age. It is also possible that it was caused by pressure washing the roof. Do not pressure wash a roof under any circumstances. It will inevitably remove aggregate. Aggregate is the shingles only protection from the harmful UV rays of the sun. When the aggregate is missing the shingles become dry and brittle. Making them susceptible to breaking off in minor wind conditions. There is no fix for this. The roofing must be replaced.






Roll roofing used on low slope/flat roofs is subject to “alligatoring.” The two examples of alligatoring to the left are beginning and extreme stages found on the same roof. Cracks resembling alligator skin begin to form. This allows water down into the cracks causing more deterioration. As the process progresses the surface begins to shrivel up until it looks like little cheese curds. At this point the underlying material is exposed to the suns UV rays and leaking occurs. The roof covering needs to be replaced.



I do not know why the squirrels do it but they eat the lead flashings off the vent pipes. Quite often I will even find dead squirrels laying around. Apparently it is not good for them. Rain water will now run down the exposed pipe and enter the attic space causing water damage. These flashing need to be replaced. There is a product on the market to protect the flashings from this type of damage. It is a plastic sleeve/cover that slips over the lead flashing. While the squirrels love the flavor of lead they are not interested in the plastic.






Leave a Reply

Your email address will not be published. Required fields are marked *