Exhibit 21


                             HEADWATERS INCORPORATED

                                  Subsidiaries


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


Global Climate Reserve

     1.   Global Climate Reserve Corporation, a Utah corporation

Headwaters Construction Materials

     1.   Headwaters Construction Materials, Inc. (fka American Construction
          Materials, Inc.), a Utah corporation

     The following subsidiaries are part of the HCM Mortar & Stucco group:

     2.   HCM Mortar & Stucco Holding, LLC, a Utah limited liability company
     3.   Best Masonry & Tool Supply, LP (fka Best Masonry & Tool Supply, Inc.),
          a Texas limited Partnership
     4.   Don's Building Supply, LP, a Texas limited partnership
     5.   HCM Mortar & Stucco Partner, LLC (fka ISG Partner, Inc.), a Utah
          limited liability company
     6.   HCM Mortar & Stucco, Inc. (fka ISG Manufactured Products, Inc.), a
          Utah corporation
     7.   HCM Utah, Inc., a Utah corporation

     The following subsidiaries are part of the HCM Block & Brick group:

     8.   HCM Block & Brick, LLC (HCM-BB), a Utah limited liability company
     9.   HCM Block & Brick General, Inc., a Utah corporation
     10.  HCM Block & Brick Partner, LLC, a Utah limited liability company
     11.  HCM Block & Brick, LP, a Texas limited partnership
     12.  HCM FlexCrete, LP, a Texas limited partnership
     13.  Palestine Concrete Tile Co., LP, a Texas limited partnership

     The following subsidiaries are part of the HCM Stone group:

     14.  Eldorado Stone LLC, a Delaware limited liability company
     15.  Chihuahua Stone LLC, a Utah limited liability company
     16.  Eagle Stone & Brick LLC, a Utah limited liability company
     17.  Eldorado G-Acquisition Co., a Utah corporation
     18.  Eldorado SC-Acquisition Co., a Utah corporation
     19.  Eldorado Stone Acquisition Co., LLC, a Delaware limited liability
          company
     20.  Eldorado Stone Funding Co., LLC, a Utah limited liability company
     21.  Eldorado Stone Operations LLC, a Utah limited liability company
     22.  HCM Stone, LLC (fka Eldorado Acquisition, LLC)
     23.  L&S Stone LLC, a Utah limited liability company
     24.  L-B Stone LLC, a Utah limited liability company
     25.  Northwest Properties LLC, a Utah limited liability company
     26.  Northwest Stone & Brick LLC, a Utah limited liability company
     27.  StoneCraft Industries LLC, a Utah limited liability company
     28.  Tempe Stone LLC, a Utah limited liability company

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     The following subsidiaries are part of the Tapco group:

     29.  Tapco Holdings, Inc., a Michigan corporation
     30.  Atlantic Shutter Systems, Inc., a South Carolina corporation
     31.  Builders Edge, Inc. (fka Specialty Building Products International
          Corporation), a Pennsylvania corporation
     32.  Comaco, Inc. (fka Kool-Vent Metal Awning Company of Pittsburgh), a
          Pennsylvania corporation
     33.  Metamora Products Corporation of Elkland, a Pennsylvania corporation
     34.  Metamora Products Corporation, a Michigan corporation
     35.  MTP, Inc., an Ohio corporation
     36.  Tapco Europe Limited (fka Landpride Limited), formed in the United
          Kingdom
     37.  Tapco International Corporation, a Michigan corporation
     38.  Vantage Building Products Corporation, a Michigan corporation
     39.  Wamco Corporation, a Michigan corporation

Headwaters Energy Services

     1.   Headwaters Energy Services Corp. (fka Headwaters Clean Coal Corp), a
          Utah corporation
     2.   Blue Flint Ethanol LLC, a Delaware limited liability company
     3.   Covol Coal Company, LLC, a Utah limited liability company
     4.   Covol Engineered Fuels, LC, a Utah limited liability company
     5.   Covol Services Corporation, a Utah corporation;
     6.   Environmental Technologies Group, LLC, a Utah limited liability
          company
     7.   Headwaters Synfuel Investments, LLC, a Utah limited liability company

Headwaters Resources

     1.   Headwaters Resources, Inc. (fka ISG Resources, Inc.), a Utah
          corporation
     2.   FlexCrete Building Systems, LC, a Utah limited liability company, of
          which HRI is a 90% member (and manager)
     3.   Florida N-Viro L.P., a Delaware limited partnership, in which VFL is a
          51.5%
     4.   Florida N-Viro Management, LLC, a Delaware limited liability company,
          of which VFL is a 52% member
     5.   Headwaters Resources Limited (fka ISG Canada, Inc.), formed in New
          Brunswick, Canada
     6.   ISG Services Corporation (fka ISG Capital Corporation), a Utah
          corporation
     7.   VFL Technology Corporation, a Pennsylvania corporation

Headwaters Technology Innovation Group

     1.   Headwaters Technology Innovation Group, Inc., a Utah corporation
     2.   Degussa Headwaters LLP, formed in the United Kingdom, of which
          Headwaters Incorporated is a 50% member
     3.   FT Solutions LLC, a Delaware limited liability company, of which HTI
          is a 50% member
     4.   Headwaters Heavy Oil, LLC (fka Headwaters Heavy Oil, Inc.), a Utah
          limited liability company
     5.   Headwaters NanoKinetix, Inc., a Utah corporation
     6.   Hydrocarbon Technologies of Canada, Inc., formed in Alberta, Canada
     7.   Hydrocarbon Technologies, Inc., a Utah corporation

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