How can I waterproof a hinged external nest box lid on my copp?

[seanb]

I had a reply with a picture but it wouldn't show up. Not sure if it's the new site format or my PC.

 

[AtholCoop]

https://www.backyardchickens.com/a/small-coop-tutorial

About halfway down the page. Works like a charm.

 

[ECBW]

I use internal nest boxes, but the concept is the same... Why not eliminate the source of the problem, operable "roof". With the roofing material, it can become heavy. It requires two hands to work it.

I would suggest making the backwall the point of access. Mount the hinges at the bottom of the door. When open, gravity keep the door open. when close, keep it tucked under the overhang of the roof and no worry about leaks.