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A floor plan is a drawing that shows a room from above, like you are looking down through the ceiling. In this project, you use grid paper to draw a room, label its side lengths, and show where furniture could fit. This helps you practice area and perimeter in a way that feels real and useful.

Architects, builders, and designers use the same ideas when they plan homes, classrooms, and playgrounds.

Key Facts

  • Area of a rectangle: A = length x width
  • Perimeter of a rectangle: P = 2 x length + 2 x width
  • A square unit, such as 1 square foot, measures the space inside a shape.
  • A linear unit, such as 1 foot, measures distance along an edge.
  • Scale example: 1 grid square = 1 foot means a 12 by 10 room is drawn as 12 squares by 10 squares.
  • Total floor area can be found by adding the areas of smaller rectangles.

Vocabulary

Floor plan
A floor plan is a drawing that shows the shape and layout of a room or building from above.
Area
Area is the amount of space inside a flat shape, measured in square units.
Perimeter
Perimeter is the total distance around the outside edge of a shape.
Scale
Scale is a rule that shows how distances on a drawing match real-life distances.
Dimension
A dimension is a measured length, width, or height used to describe the size of an object or space.

Common Mistakes to Avoid

  • Counting inside squares for perimeter: Perimeter is the distance around the outside edge, so count only the outer sides, not every grid square inside the room.
  • Writing area with regular units: Area must use square units, such as square feet or square meters, because it measures a two-dimensional surface.
  • Forgetting the scale: If 1 grid square equals 2 feet, each square is not just 1 foot wide, so all real measurements must use the scale.
  • Adding furniture area to room area: Furniture takes up part of the floor, but it does not increase the total area of the room.

Practice Questions

  1. 1 A rectangular bedroom is 12 feet long and 9 feet wide. What are its area and perimeter?
  2. 2 On a floor plan, 1 grid square represents 1 foot. A closet is drawn as 3 squares by 5 squares. What is the closet's area in square feet, and what is its perimeter in feet?
  3. 3 A student draws a room with the correct area but the wrong perimeter. Explain how two rooms can have the same area but different perimeters.