Interior Doors, Frames and Trim This chapter covers interior doors, trim and cabinetry installed in the finishing stages of house construction. wide. The standard thickness of interior doors is 35 mm (13⁄8 in.). They are available in various widths and heights. The decorative treatment for interior doors and trim may be paint or natural finish with stain and varnish. Prefinished products are also available. The finish selected for woodwork in various rooms may determine the type or species of wood to be used. Install doors so that they open in the direction of natural entry. Doors should also swing against a blank wall wherever possible and not be obstructed by other swinging doors. INTERIOR DOORS Interior doors are used to separate living areas and provide privacy. Options include single and double swinging doors, and pocket doors. Sliding doors and folding doors are popular choices for clothes closets. Bedroom and passageway doors must be at least 760 mm (30 in.) wide and 1.98 m (6 ft. 8 in.) high. Doors providing access to laundry and utility rooms must be at least 810 mm (32 in.) Interior doors are usually made of wood, wood composites or plastic. There are two general types of interior doors: flush and panel. The flush door is made up of facings of plywood or other sheet material glued to a light framework. For a natural or varnished finish, the face plies are selected for quality and colour. For a painted finish, the face plies may be less expensive or non-select grades. The panel door consists of solid stiles and rails with panel fillers of various materials. These create relief panels in the door and are available in a number of designs.