476 Interiors Copyright Goodheart-Willcox Co., Inc. ■ Construction model. This is a scaled model indicating construction details or building components. ■ Presentation model. Also called a finish or working model, this is a rough, scaled replication of what the final space or building will look like once built. ■ Daylighting model. This model helps the designer study the shift of daylight across and through an interior during different years and seasons. These models can also be computer generated. ■ Parti model. A type of conceptual model, a parti model is an abstract study of geometric shapes or series of lines and forms. A designer uses it to develop a floor plan. ■ Rip and tear model. These informal models help capture the ideation process. Materials used to make them may be old boxes, paper, plastic, wood, and sheet metal—often scraps of materials the designer does not purchase. ■ Site model. This model places emphasis on architecture to site rather than the interior. Materials and tools for handheld models vary in construction capabilities, composition, and expense. Some are very flimsy, such as cardstock paper, while others are quite rigid, such as balsa wood. Designers can use them in combination, but they are often of pris- tine, monochromatic colors to encourage investiga- tion of the spaces and shapes. The materials come in sheets and can be cut to specific shapes and measure- ments. Professional-looking models (whether concept or presentation) also require the right adhesives to properly hold them together. Adhesives include glue, tape, straight pins, knives (both artist and utility), and pliers. When building presentation models, a few common construction materials include ■ Balsa wood. Strong and lightweight with a tight grain, balsa wood is easy to cut and available in many thicknesses, Figure 13-46. ■ Cardboard. Easy to cut and inexpensive to purchase, cardboard is paper layers glued together. ■ Chipboard. Semi-rigid paperboard comprised of pressed and glued wood chips, chipboard is low in cost and easy to cut. ■ Foam core. Available in many colors and widths, foam core (or foam board) is rigid polystyrene foam that is sandwiched between two pieces of paper. It is easy to cut, but must be scored with a new knife blade several times to achieve a clean cut. ■ Mat board. Available in many colors, mat board (or presentation board) is paperboard with a pulp core. The cut edges look best when the mat board’s core matches the surface paper color. ■ Museum board. Expensive paperboard of high archival (acid-free) quality, museum board is available in neutral colors of white, beige, and black, and comes in several thicknesses. Handle museum board with disposable, white-cotton gloves to prevent hand oils from adhering to the surface. ■ Poster board. Easy to cut, poster board is a thin cardboard. Balsa Wood Models Lisa Taylor, Senior Design Student, Colorado State University Figure 13-46 Balsa wood is a lightweight material that can be used to create handheld models.