Sheet metal roofing

Claim 1

A METAL ROOF COMPRISING A PLURALITY OF ELONGATED METAL SHEETS AND A PLURALITY OF JOINT STRIPS, SAID METAL SHEETS AND SAID JOINT STRIPS BEING HORIZONTALLY MOUNTED ON A SLOPING SURFACE TO BE ROOFED AND SECURED PARALLEL TO EACH OTHER, SAID JOINT STRIPS EACH COMPRISING A FOLDED METAL PIECE OF UNITARY CONSTRUCTION HAVING AN UNDERLYING PORTION WHICH SEATS SUBSTANTIALLY FLUSH ON SAID SURFACE AND UNDERLIES THE UPPER END OF A FIRST OF SAID METAL SHEETS, AN INTERMEDIATE PORTION FOLDED DOWN SUBSTANTIALLY AGAINST SAID UNDERLYING PORTION AND FORMING THEREWITH A FIRST RECESS IN WHICH THE UPPER END OF SAID FIRST METAL SHEET FITS SNUGLY, SAID UNDERLYING AND INTERMEDIATE PORTIONS BEING OF A REDUCED COMPOSITE THICKNESS ADJACENT SAID FOLD WITH RESPECT TO THE COMPOSITE THICKNESS OF SAID PORTIONS AND SAID FIRST METAL SHEET ADJACENT THE MOUTH OF SAID FIRST RECESS TO DEFINE A FASTENING MARGIN EXTENDING LONGITUDINALLY ALONG THE JOINT STRIP AT THE FOLD OF SAID UNDERLYING AND SAID INTERMEDIATE PORTIONS, FASTENING MEANS RECEIVED BY SAID FASTENING MARGIN FOR CONNECTING SAID JOINT STRIP TO SAID SURFACE, AND OVERLYING PORTION FOLDED UP FROM SAID INTERMEDIATE PORTION AND BACK OVER SAID INTERMEDIATE PORTION AND FORMING THEREWITH A SECOND RECESS IN WHICH THE LOWER END OF A SECOND OF SAID METAL SHEETS FITS SNUGLY, AND OUTLET MEANS PROVIDED AT THE BASE OF SAID OVERLYING PORTION FOR RELEASING ANY MOISTURE WHICH MAY PENETRATE INTO SAID SECOND RECESS.