Abstract: An adjustable sill assembly includes a substrate base; a sill plate connected with the substrate base; a riser having a top and two downwardly-extending legs defining an interior of the riser, said interior of the riser having a first flange and a second flange angling downward and toward one another; and means for supporting the riser on the substrate base including an adjusting screw and a corresponding T-nut, said adjusting screw having a head adjacent the substrate base and said T-nut slideably supported by the first and second flanges and wherein the riser is supported by the substrate base by threading the adjusting screw into the T-nut. In another embodiment, the adjusting screw is provided with a head that extends beyond at least one of the downwardly-extending legs of the riser to allow engagement and turning of the adjusting screw from the side of the riser.

Abstract: An adjustable sill assembly includes an elongated substrate base composed of a molded composite material and defining a T-shaped slot extending along the length of the substrate base and open to a top surface of the substrate base; a sill plate connected with the substrate base; a riser having a top and two downwardly-extending legs defining an interior of the riser, the interior of the riser having a pair of flanges angling downward and toward one another; and means for connecting the substrate base with the riser including a T-nut having a flange and a corresponding screw, the T-nut being slidebly and non-rotatably supported within the T-shaped slot and the screw being rotatably and slideably supported by the pair of flanges and wherein the riser is secured to the substrate base by inserting the screw into the T-nut.

Abstract: An extruded aluminum sill member is supported by and attached to a wood base member which also supports a longitudinally extending inner wood trim member. The sill, base and trim members define a longitudinally extending cavity which receives a vertically adjustable rail member. The rail member has longitudinally spaced captive screws which are threaded into inverted T-nuts confined within laterally extending slots formed within the wood base member, and the trim member covers the slots. The sill member also extends under a jamb or mullion and a fixed side panel, and a snap-in extruded plastic cap covers the cavity under the panel and has an upwardly projecting and inwardly curved flange with a flexible lip for engaging the outer surface of the panel to form a water-tight seal.