I had a skylight in a small barn I have on my property which had a branch go through one of the plastic bubble like skylights. I have been trying to find a replacement for it but can’t find any that match.
It doesn’t need to match the old one but everything I find is flat around the edges or pre-flashed. Anyone happen to know the name of what was previously on there where it has sides on it too?
Here is a picture of the skylight hole itself. The dimensions are
Inner - 21 inch 3/4 x 21 inch 3/4
Outer - 26 inch 1/8 x 26 inch 1/8
 

I found this after I posted, so I guess it is called Dome over Frame but can’t seem to find any online.

- That looks like an RV skylight. Maybe ask an RV dealership where you could find one with the correct dimensions? - It really looks like one of the ones on my Airstream. It’s almost exactly the same size even. This company makes well-regarded replacements. - Totally it! On their measuring instructions page they even have a picture of an old one with the flange just like OPs - Yep that is it! Thanks so much for the help! Man this was a pain to try to find. Now to contact them! 
 
 
 
- I used this site in the past for a custom sized plastic dome for a cosplay and they were great and a good price - I will check them out and see what they say. Thanks! - edit I got a reply stating the following “Our skylights do not have the downward turned flange, just a flat flange.”. - Ah, alright. Sorry about that. 
 
 
- It looks like a curb mount dome but the closest I can find is this: - Yeah its weird, I am starting to think it may be best to just remove the skylight all together. - Alternatively you could replace the entire assembly with a comparable one. 
 
 


