First time posting. I’m a new inspector and did my first inspection today. A real nightmare. Homeowner additions were caving in. At any rate, ran into this roof appearance I’ve never seen before. Any ideas what may have caused this. The entire west side was textured with these bumps on the shingles.
Hope this pic posts. Never uploaded one before.
Looks blistered
Here is one perspective on the subject
http://www.iko.com/misc/FaqPdf/CRC%20Tech%20Bull%20Blistering.pdf
Thank you. Being in new construction all my life, I’ve nevr seen this before.
Don’t take what I post as fact I wasn’t there doing the inspection and would never write in stone or attest to the actual type of damage from a picture.
You definately should note this for a roofer to determine the type, cause and remedy of any damage you find when and if you are the least bit uncertain of the materials conditions.
BTW, WELCOME!
Look forward to seeing you on the boards more often now that you’ve broken the ice.
Wasn’t so bad now was it? 
Funny there is no reference to manufacturing quality control, materials substitution, etc. Bill Rose has been claiming shingle quality seems to be slipping. I’ve seen this up here with shingles losing granules severely in 13-15 years, not the 18-25 that I used to see in the 1980’s!!
Chris
Welcome to INTERNACHI and the boards.
How old is the roof in question? The pic looks to me like something may have either been applied or somehow drifted onto the roofing material. Based on your visual inspection (on the jobsite), does that seem possible?
I agree with Barry, defer to a Prof. Roofing Contr. to verify condition and remedy.
Good Luck
Thank you. Been here a couple months, but, been very bust setting up my company and all that goes with it. So, mostly just spent a lot of time reading posts and learning.
The roof was actually a minor problem compared to the rest of the home so I just deferred it. It was a 33 year old home and had extensive roof leaks in the past so something very well may have been applied.
The only things in the home that actually were functioning as intended were the stove and sewer lines. The garage had no footings, a three in slope and a feeble attempt to jack it up in the past, which was failing.
The worst thing though was an addition where a 24 foot exterior bearing wall had been removed with nothing added to replace it. The only thing holding the roof up were a few 16P nails and sheetrock.
The client declined to purchase.
It was a very educational first inspection. Should make the rest look easy.
Congratulations! On your very first inspection you’ll get to hear a realestator say “Darn inspector blew my deal over little things”. 
Welcome to the BB.