How to install T-lock shingles 

I can’t make any promises lol

You are wrong. He installed them correctly but didn’t use any underlayment

Yeah all that work and don’t spent $20 on felt seems crazy to me.

they are discontinued/won't be covered because if a *single* shingle gets damaged you need to replace the entire roof to fix that one shingle.

I don't know why this cat isn't using any vapor barrier. I was a roofer in central Kansas for over 20 years and I've tore off hundreds of roofs with T locks and when they were put down on the original decking there was always tar paper. Usually those shingles were over laid. Either over wood or over asphalt over wood. It used to be the wood shingles were considered decking and people would have three layers of roofing. I got to be the generation that had the privilege of tearing all those old dusty roofs off. Then we nailed 7/16" OSB over the space sheeting from the wood shingles. It ruined my lungs breathing in all that nasty dust off the old cedar shingles. You see when all of the shingles were cedar they had to leave a two to three inch gap between the 1×6s so that air could get under the shingles and dry them out. Otherwise the roofs would have prematurely rotted away underneath while appearing fine on the top. Now this dude here is going to have the decking rot away under the Tlock shingles because he didn't use a vapor barrier. And he has plywood decking. The absolute worst there is when it comes to moisture warp and rot when exposed to even small amounts of moisture. Even in the form of vapor. So there is your roofing education for the day thank you very much and GOD bless you.

If you do you roof properly you don’t need any underlay in my experience I’ve torn off roofs that are 40+ years old with no underlay and the plywood is brand new underneath, like a lot of things nowadays, underlay is just an extraneous money grab

I ? That too

No I believe that is just a waste of resources if you shingle properly in the first place that’s all you need! I’ve seen roof decks that are 100 years old and have never had any of that fancy stuff and they are in perfect shape

Ty Austin, I had heard that but no reasoning behind it. It does seem to be the local practice.

@@AustinTischler I was wondering about the need for a water barrier as well. Thank you for explaining that Austin! ☘️☘️☘️

I found them in an old barn, they have been discontinued for about 20 years

That’s a little far for me lol I usually keep things under a 30 mile radius of home