Ridge Cap Necessary

On a DIY website I occasionally check out and see if I can help anyone with the little knowledge I have, a lady posted this.

“We are in a semi-detached home & have just replaced our roof. Our attached neighbor did not. Where our shingles meet the neighbors, should we not have a ‘cap’ or something where the two different types & color shingles meet?
On houses down the street where two different roofs come together, there is a line of shingles that cap the border. Is this just aesthetic or is it functional?”

I explained they are functional and I have never seen a method where this is acceptable. Her roofer on the other hand claims it is perfectly fine.

"Caps are required for install that have a shingle layer difference. Not installing caps works better because there are no exposed nails on the slope downward which can cause a leak. Creating a straight line with the Landmark 30 and using plastic cement gives a 100 % seal, which is the best option in your case. We install the correct procedure required for the job, therefore we have certainty that warranty work will not be necessary. The reason why other companies use caps is because its less labour intensive than installing a straight cut. "

What do you guys think? Am I the crazy one? I can post the link to the page so you can see the whole conversation if you would like.

I read that too.Depending how they were tied in I guess,would determine the need for ridgecap.She needs to post some pics…

Agreed I want pics

I saw that too. I’ve weaved them, and installed some form of cap/step combo. Each one is different. Never used black mammy. That’s not a roofer item for tying in a roof. JL’s seem to favor it right much though. #1 tool in their kit.

Yeah Tinner, I have seen them weaved and the step combo you mentioned but to me it sounded like he just folded over the tops of the shingle, nailed down the otherside and put some cement over it.

using that sort of logic why would you ever install cap shingles? Less labor intensive to install caps as opposed to just flopping the shingle over and tarring is just BS imo

If they are weaved to togather then there is no need for tar.

Who gets to pick the cap color? Her or her neighbor with the different color shingles

just reread the first post and I misunderstood what they were saying, when I heard cap shingles i assumed they meant the ridge and now I see they mean the joint where the field shingles meet. Like RooferR says if they are weaved in right should be no need for tar or a cap shingle

I have never done it before, but why wouldn’t you just cut the shingles like the OP described and instead of using tar use metal flashing in a step type manner?

This would be water tight and look good, as much as two different color roofs connected together can look.