Abstract: A low temperature gas-fired or electrically heated oven and warming unit for domestic purposes having a chamber enclosed by walls and a door at the front. The chamber is variable in volume, for example by being vertically extensible by having overlapping, relatively movable wall portions at the side and back and a door which automatically adjusts to the volume of the chamber for example by being of the tambour or roller shutter type. The unit can be fixed by the top section under a kitchen wall unit and extended downwards for use. Removable, lazy-tongs linkages at the sides of the unit control the extension of the chamber and are jointly operated by a single adjustment control. Shelf supports on the linkages move to alter the spacing of the shelves as the chamber volume is varied.