wall outlet covers

This is not a prob for a pro, but i did something to cover (pun intended) a common occurence and would love a second opinion.

scenario:
wall was recovered with thick paneling, outlet box not moved to flush for cover.
no prob most of the time, but oh no.
My second floor apartment has got an incredible up and down flow from morning till , well, next morning. (up all morning, down all night). In this new apartment i just rented i found it not only to release a bad stench without covers, dust has caked the all metal box right to the wire screws, and it was a noticable burn! I had to do something right away
This is what I did:
With very thin aluminum sheet painted and plastic covered cardboard I made an exact fit flush for the cover of the outlet box. It is still recessed too much to be normal for a normal cover, but will accept one alot safer than it wasn't.It sealed the box, and kept the wall from leaking in at same time.Is my ingenuity "legal"?