Convert open Polysurface to solid

RoofHelp.3dm (18.2 MB)
Hello I am having trouble converting this object to a solid. I want to boolean union it but it keeps saying it failed. I am pretty new to rhino so I understand my design may have some errors. Are there any quick fixes to make this object into a solid?

Thanks

Hi Bryce -the grid thing has many many duplicate and unfortunately (cannot be found with SelDup) near-duplicate faces as well as internal faces… the grid thing is a mess - I would start that again, to be honest. How did you make it? It looks like you could draw a grid in curves and extrude it to get what I think you want.

Something like this
RoofCleanup.3dm (4.5 MB)

-Pascal