Exhibit 23.1 CONSENT OF INDEPENDENT AUDITORS We consent to the incorporation by reference in the Registration Statements on Form S-3 (File Nos. 333-34488, 333-67371, 333-76724, 333-79385, 333-96919 and 333-100322) and on Form S-8 (File Nos. 333-39674, 333-39676, 333-39678 and 333-103527) of Headwaters Incorporated of our report dated October 31, 2003 with respect to the consolidated financial statements of Headwaters Incorporated included in this Annual Report (Form 10-K) for the year ended September 30, 2003. /s/ Ernst & Young LLP Salt Lake City, Utah December 1, 2003