Interesting roof installation! 
Odd…Gussets or black lines?
That is a screwy but there are “3 tab traditional” shingle installation patterns where the tab slots do not line up in every 2nd row as we are used to seeing…one is the Certainteed “**[FONT=Futura-CondensedBold][size=2]
EIGHT-COURSE, FIVE-INCH, STEPPED-OFF DIAGONAL METHOD”. **[/size][/FONT]
Another I saw a few years ago had shingles offset by 1/3 tab (if I remember correctly) not the standard 1/2 tab!
It’s straight
Not even offset by one third of a tab. Substanial water intrusion causing sheathing damage at the center area of this porch roof. This is one that I was glad I did not walk!
In the late 50’s and 60’s roofing pattern and assorted sihngle sizing, shapes, color, and dimension where the norm. and patters where all the rage. I still see some patterned roofs in St.ANN’S . A little collage town on the western side of Montreal. I will try to take photos.
As long as a mathematical equation is used when measuring the pattern out, everything is OK.
It is good for a laugh!
Yes sir. You would know. Thanks. 
Any link to the [FONT=Futura-CondensedBold][size=2]“EIGHT-COURSE, FIVE-INCH, STEPPED-OFF DIAGONAL METHOD”
[/size][/FONT][FONT=Futura-CondensedBold][size=2]Marcel will have it.[/size][/FONT][FONT=Futura-CondensedBold][size=2]
[/size][/FONT][FONT=Futura-CondensedBold][size=2]Brian there use to be many patterns and shingle installation was a valued trade.
Roofs lasted many years beyond there guarantee. I have witnessed 40 year roofs with 6/12 pitch.
Shingle roofers call them self roofers, when all they are is tile men.[/size][/FONT][FONT=Futura-CondensedBold][size=2].
[/size][/FONT][FONT=Futura-CondensedBold][size=2]I saw the term used on a government website.[/size][/FONT][FONT=Futura-CondensedBold][size=2] [/size][/FONT][FONT=Futura-CondensedBold][size=2]They were not speaking of Tera Cota clay Spanish or cement tiling.
Asphalt shingle tiler**s **[/size][/FONT][FONT=Futura-CondensedBold][size=2]wanted. It might have been a misprint or edited wrong.[/size][/FONT][FONT=Futura-CondensedBold][size=2]
[/size][/FONT][FONT=Futura-CondensedBold][size=2]The trade is dead and the product is bad in most cases.[/size][/FONT][FONT=Futura-CondensedBold][size=2]
[/size][/FONT][FONT=Futura-CondensedBold][size=2]I will say it again. the public is being bamboozled.[/size][/FONT][FONT=Futura-CondensedBold][size=2]
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