Exhibit 21.1 Subsidiaries of Atrium Companies, Inc. Atrium Door and Window Company-West Coast, a Texas corporation Atrium Door and Window Company of the Northeast, a Connecticut corporation Atrium Door and Window Company of New York, a Connecticut corporation Atrium Door and Window Company of Arizona, a Delaware corporation Atrium Door and Window Company of New England, Inc., a Connecticut corporation Door Holdings, Inc., a Delaware corporation R.G. Darby Company, Inc., an Alabama corporation R. G. Darby Company-South, a Delaware corporation Total Trim, Inc., an Alabama corporation Total Trim, Inc.-South, a Delaware corporation Wing Industries Holdings, Inc., a Delaware corporation Wing Industries, Inc., a Texas corporation Heat, Inc., a Delaware corporation H.I.G. Vinyl, Inc., a Delaware corporation Champagne Industries, Inc., a Colorado corporation Thermal Industries, Inc., a Delaware corporation Best Built, Inc., a Delaware corporation