Interior Design and Environment
The Interior Design and Environment domain covers elements and principles of design, colour, lighting, furniture arrangement, finishes and the immediate environment. Questions ask you to design a described room and justify each choice.
Elements
Line, form, shape, space, texture, colour, pattern and light. Horizontal lines broaden; vertical lines heighten; curved lines soften.
Principles
Balance, rhythm, proportion and scale, emphasis, harmony and unity. A room should have one dominant element, not five competing ones.
Colour
Hue is the name, value is lightness/darkness, intensity is saturation. Primary (red, yellow, blue), secondary and tertiary. Schemes: monochromatic (one hue), analogous (neighbours on the wheel), complementary (opposites), split-complementary, triad. Warm colours advance; cool colours recede.
Lighting
Ambient (general), task (reading, cooking), accent (display). Natural light changes through the day; artificial light needs the right level and colour temperature. LED is energy-efficient.
Furniture and finishes
Scale furniture to the room; keep 75–90 cm circulation paths; group seating for conversation. Hard finishes reflect sound; soft furnishings absorb it.
Worked example. Make a small north-facing bedroom look larger and warmer. Use light, warm-neutral walls, one accent wall, a large mirror facing the window, vertical stripes on curtains, low-profile furniture and layered lighting. Label each choice with its principle.
Traps. Confusing value and intensity; calling adjacent colours complementary; and adding many focal points, which destroys emphasis.