mmcelroy1

Can I install 12" x 12" ridge caps over my worn, existing 8"w x 12" ridge caps?......Thank you

oldognewtrick

Can you? Sure you can. Would I reccomend it? No! Remove the old capping and install the new ones.

joecaption

And why would you want to? There never going to stay stuck down and will soon fail.
Since you going to be taking them off, why not add a ridge vent and this time pay a little more and use the thicker ridge caps. There 3 times thicker then just cheaping out and using 3 tab shingle cap.