of this first course 120 of tiles once the first course 120 has been applied similar thick beads 125 having lengths l 2 which match the length of the second course 126 of tiles are applied to the roof substrate 23 and the first course 120 of tiles although the use of the two component foam 114 in this type of roof construction 100 is effective enough to adhere the roof tiles 102 in place upon the roof 22 such two component foams are generally expensive furthermore the teachings of the 39 342 patent direct one skilled in the art to apply an adhesive foam bead for the entire length or substantially the entire length of the tiles 116 this fashion of adhesive foam application promotes the use of more adhesive foam than necessary it has been discovered with the development of the present invention that a more economical one component adhesive including an adhesive foam may be used to reliably adhere roof tiles to a roof substrate and in a particular pattern which uses significantly less adhesive than taught by the aforesaid 39 342 patent and other prior art roof adhesive foam applications in an important aspect of the present invention a one component adhesive is utilized to adhere the roof tiles to the roof substrate one advantage the use of one component adhesives especially one component adhesive foams have over two components adhesive foams is cost another advantage is that one component adhesives are dispensed from single pressurized containers which avoids.