Architectural drawings are the language between the designer and the builder. They show not just what a building looks like but what it is made of, how it goes together, and how it meets the requirements of building codes and client expectations. Understanding each drawing type — what it shows, what scale it is drawn at, and what information it must contain — is fundamental for anyone working in construction.
Floor Plans
A floor plan is a horizontal section cut through a building, typically at about 1200mm (4 feet) above the floor level, looking down. It shows wall locations and thicknesses, door and window positions (with swing direction for doors), room names and areas, column grid references, stair locations, and dimensions. Floor plans are the primary navigation tool for every other drawing in the set — sections, elevations, and details all reference back to locations shown on the plan.
Each level of a multi-storey building has its own floor plan sheet. Roof plans show the roof drainage, parapet heights, roof access, and equipment locations.
Elevations
Elevations are orthographic projections of the exterior faces of a building — North, South, East, and West elevations are the standard set. They show the building’s overall height, floor-to-floor heights referenced to a datum, window and door positions in elevation, exterior material changes and finishes, and roof form. Interior elevations show the same information for walls inside rooms — particularly critical for kitchens, bathrooms, and feature walls.
Sections
A section is a vertical cut through the building showing the internal organisation from foundation to roof. Building sections — typically drawn at 1:100 or 1:50 — reveal floor-to-floor heights, ceiling heights, structural depth, and the relationship between floors, walls, and the roof structure. Wall sections are drawn at 1:20 or 1:10 and show the detailed construction of the wall assembly: foundations, damp-proof courses, insulation layers, cladding systems, and how the wall meets the floor and roof.
Details
Details are large-scale drawings — typically 1:5 or 1:2 — of specific construction junctions: how a window is fixed and flashed, how a roof edge is detailed, how a balustrade post is anchored. Details answer the questions that cannot be resolved at the scale of the floor plan or section. They are the most construction-critical drawings in the set — a contractor builds from the detail, not the elevation.
Reflected Ceiling Plans
A reflected ceiling plan (RCP) shows the ceiling as if it were reflected in a mirror on the floor — you are looking up at the ceiling but drawn in plan orientation. RCPs show ceiling heights and changes, ceiling grid layouts, light fixture positions, sprinkler heads, HVAC grilles, smoke detectors, and access hatches. The RCP is the coordination drawing for the underside of a floor — it is where architectural, mechanical, and electrical drawings overlap most heavily.
Door and Window Schedules
Every door and window in an architectural set is tagged with a mark number that references a schedule. The door schedule lists every door by mark: type, size (width and height), frame material, fire rating, hardware set, and any special requirements. The window schedule covers glazing type, frame colour, U-value, and sill height. Schedules keep the drawings clean by removing repetitive annotation and provide a direct procurement reference for the contractor.
Finish Schedules and Room Data Sheets
Finish schedules list the floor, wall, and ceiling finish materials for every room. Room data sheets are used on complex projects (hospitals, laboratories) to document the full technical requirements of each room: finishes, temperature, humidity, access controls, medical gas points, and power requirements.
Conclusion
The architectural drawing set is a coordinated system, not a collection of individual drawings. Floor plans reference sections; sections reference details; details reference specifications. Reading any single drawing in isolation gives an incomplete picture. Understanding how the drawing types relate to each other — and being able to navigate from a plan to its section to the relevant detail — is the skill that separates someone who can read drawings from someone who can actually build from them.