Exhibit 21

HEADWATERS INCORPORATED

Subsidiaries

The ownership of each direct and indirect subsidiary is 100%, except where indicated below.

Construction Materials



| |  |  | Headwaters Construction Materials, Inc., a Utah corporation
| | - |  | -----------------------------------------------------------

The following subsidiaries are part of HCMs block, mortar and stucco group:



| |  |  | Best Masonry & Tool Supply, LLC, a Texas limited liability company
| | - |  | ------------------------------------------------------------------



| |  |  | Dons Building Supply, LLC, a Texas limited liability company
| | - |  | -------------------------------------------------------------



| |  |  | FlexCrete Building Systems, LC, a Utah limited liability company, of which HRI is a 90% member
| | - |  | ----------------------------------------------------------------------------------------------



| |  |  | Headwaters Construction Materials, LLC, a Texas limited liability company
| | - |  | -------------------------------------------------------------------------



| |  |  | HCM FlexCrete, LLC, a Texas limited liability company
| | - |  | -----------------------------------------------------



| |  |  | HCM Utah, Inc., a Utah corporation
| | - |  | ----------------------------------

The following subsidiaries are part of HCMs manufactured architectural stone group:



| |  |  | Chihuahua Stone LLC, a Utah limited liability company
| | - |  | -----------------------------------------------------



| |  |  | Eldorado G-Acquisition Co., a Utah corporation
| | - |  | ----------------------------------------------



| |  |  | Eldorado SC-Acquisition Co., a Utah corporation
| | - |  | -----------------------------------------------



| |  |  | Eldorado Stone LLC, a Delaware limited liability company
| | - |  | --------------------------------------------------------



| |  |  | Eldorado Stone Acquisition Co., LLC, a Delaware limited liability company
| | - |  | -------------------------------------------------------------------------



| |  |  | Eldorado Stone Funding Co., LLC, a Utah limited liability company
| | - |  | -----------------------------------------------------------------



| |  |  | Eldorado Stone Operations LLC, a Utah limited liability company
| | - |  | ---------------------------------------------------------------



| |  |  | Eldorado Stone Philippines, Inc., a Philippines corporation
| | - |  | -----------------------------------------------------------



| |  |  | HCM Stone, LLC, a Utah limited liability company
| | - |  | ------------------------------------------------



| |  |  | L-B Stone LLC, a Utah limited liability company
| | - |  | -----------------------------------------------



| |  |  | Piedras Headwaters, S. de R.L. de C.V., a Mexican limited liability company
| | - |  | ---------------------------------------------------------------------------

The following subsidiaries are part of HCMs shutters, siding and tools group:



| |  |  | Atlantic Shutter Systems, Inc., a South Carolina corporation
| | - |  | ------------------------------------------------------------



| |  |  | Metamora Products Corporation of Elkland, a Pennsylvania corporation
| | - |  | --------------------------------------------------------------------



| |  |  | Metamora Products Corporation, a Michigan corporation
| | - |  | -----------------------------------------------------



| |  |  | MTP, Inc., an Ohio corporation
| | - |  | ------------------------------



| |  |  | Tapco Europe Limited, formed in the United Kingdom
| | - |  | --------------------------------------------------



| |  |  | Tapco International Corporation, a Michigan corporation
| | - |  | -------------------------------------------------------

Alternative Energy



| |  |  | Headwaters Energy Services Corp., a Utah corporation
| | - |  | ----------------------------------------------------

The following subsidiaries are part of HES coal cleaning group:



| |  |  | Covol Engineered Fuels, LC, a Utah limited liability company
| | - |  | ------------------------------------------------------------



| |  |  | Covol Fuels No. 2, LLC, a Utah limited liability company
| | - |  | --------------------------------------------------------



| |  |  | Covol Fuels No. 3, LLC, a Utah limited liability company
| | - |  | --------------------------------------------------------



| |  |  | Covol Fuels No. 4, LLC, a Utah limited liability company
| | - |  | --------------------------------------------------------



| |  |  | Covol Fuels No. 5, LLC, a Utah limited liability company
| | - |  | --------------------------------------------------------



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The following subsidiaries are part of HES alternative coal-based synthetic fuel group:



| |  |  | Covol Coal Company, LLC, a Utah limited liability company
| | - |  | ---------------------------------------------------------



| |  |  | Covol Services Corporation, a Utah corporation;
| | - |  | -----------------------------------------------



| |  |  | Environmental Technologies Group, LLC, a Utah limited liability company
| | - |  | -----------------------------------------------------------------------



| |  |  | Headwaters Synfuel Investments, LLC, a Utah limited liability company
| | - |  | ---------------------------------------------------------------------

The following subsidiaries are part of HES liquid fuels group:



| |  |  | American Lignite Energy, LLC, a Delaware limited liability company, of which Headwaters Energy Services Corp. is a 40% member
| | - |  | -----------------------------------------------------------------------------------------------------------------------------



| |  |  | Blue Flint Ethanol LLC, a Delaware limited liability company
| | - |  | ------------------------------------------------------------



| |  |  | Headwaters CTL, LLC, a Utah limited liability company
| | - |  | -----------------------------------------------------



| |  |  | Headwaters Ethanol Operators, LLC, a Utah limited liability company
| | - |  | -------------------------------------------------------------------



| |  |  | HES Ethanol Holdings, LLC, a Utah limited liability company
| | - |  | -----------------------------------------------------------

The following subsidiaries are part of Headwaters specialty chemical group:



| |  |  | Degussa Headwaters LLP, formed in the United Kingdom, of which Headwaters Incorporated is a 50% member
| | - |  | ------------------------------------------------------------------------------------------------------



| |  |  | Degussa Headwaters Korea Co., Ltd., a Korean limited liability company, of which Headwaters Incorporated is a 50% member
| | - |  | ------------------------------------------------------------------------------------------------------------------------



| |  |  | Headwaters Heavy Oil, LLC, a Utah limited liability company
| | - |  | -----------------------------------------------------------



| |  |  | Headwaters Heavy Oil Canada, ULC, formed in Nova Scotia, Canada
| | - |  | ---------------------------------------------------------------



| |  |  | Headwaters Refinery Investments, Inc., a Utah corporation
| | - |  | ---------------------------------------------------------

Coal Combustion Products



| |  |  | Headwaters Resources, Inc., a Utah corporation
| | - |  | ----------------------------------------------



| |  |  | Headwaters Resources Limited, formed in New Brunswick, Canada
| | - |  | -------------------------------------------------------------



| |  |  | Headwaters Services Corporation, a Utah corporation
| | - |  | ---------------------------------------------------



| |  |  | VFL Technology Corporation, a Pennsylvania corporation
| | - |  | ------------------------------------------------------

Research and Development



| |  |  | Headwaters Technology Innovation Group, Inc., a Utah corporation
| | - |  | ----------------------------------------------------------------

Other Subsidiaries



| |  |  | Global Climate Reserve Corporation, a Utah corporation
| | - |  | ------------------------------------------------------