How to Read Blueprints: Floor Plan Symbols & Scales

What is a floor plan scale?

The ratio of the drawing size to the actual size of the building (e.g., 1:100 means 1 cm on paper equals 100 cm in real life).

What does a double solid line represent on a plan?

It represents a solid brick or concrete wall, with the thickness indicating if it is a main structural wall or a partition wall.

What does a curved arc line near a door mean?

It shows the direction and path the door will swing when opened, helping you plan furniture placements.

What is an electrical symbol layout?

A dedicated drawing showing the positions of switchboards, lights, fans, power outlets, AC points, and distribution boards.

What does a dashed line represent on a floor plan?

Dashed lines represent hidden structures or features above head level, such as ceiling beams, arches, or loft boundaries.

What is carpet area vs. super built-up area?

Carpet area is the inner usable floor area. Super built-up area includes walls, common corridors, lift shafts, and balcony spaces.

What symbol represents a window on a blueprint?

A window is represented by thin double lines or a narrow rectangle inserted within the thick solid wall lines.

What is a sectional drawing?

A drawing showing a vertical cut view of the building, detailing floor heights, roof thickness, and staircase profiles.

What is a site plan?

A map showing the complete plot boundaries, including the building footprint, roads, pipelines, and garden setups.

How do I verify room dimensions on paper?

Read the dimension text listed inside each room box (e.g. 10' x 12') rather than scaling the paper drawing manually.

A Guide to Floor Plan Symbols and Architectural Blueprints