enter image description hereI have a 30 x 15 stick built shed with composition shingles over 1/2" sheathing. I would like to take 12 lineal feet off the end, remove the roofing and sheathing and install corrugated plastic to turn it into a greenhouse. How do I make that joint between the remaining composition roof and the corrugated plastic weatherproof?


This is what I'm going to try. Any comments would be appreciated.

  • Did you ever get this resolved? If so, please give a check-mark to the answer that helped you the most, or write up your own answer explaining what you did to get it fixed and give yourself a check mark. That will help others with this kind of problem know that this has a resolution and is a good place to look for their answer.
    – FreeMan
    Aug 15, 2020 at 20:43

2 Answers 2


I'd think you'd abut the two roofing types and overlay a flashing, lapping onto each 6 inches or more. The outcome would be similar to any hip or ridge.


Plastic does not last more than a couple years. I have used about 3 types on my shed roof all failed. I "bit the bullet" and put in 1/4 plate glass , 2 X 4 ft. panels. They have survived a hail storm which damaged our composition roof so badly that the insurance company replaced it.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.