# Architectural Plan vs Floor Plan vs Site Plan vs Section vs Elevation: Types of Architectural Drawings Explained **An architectural plan is not one drawing but a family of them, and each member answers a different question.** The floor plan shows how a level is laid out. The site plan shows how the building sits on its land. The section shows the building cut vertically. The elevation shows what each outside face looks like. Together with a roof plan and a few details they describe a building well enough to discuss it, price it and build it. People searching for a "building plan", "architecture plan" or "blueprint" are usually after one of these. This guide explains what each drawing shows, how to read it, and which one answers which question. --- ## The short version | Drawing | Direction of view | Answers the question | Typical scale | |---|---|---|---| | Site plan | From above, whole plot | Where is the building on the land, how do people and cars get to it? | 1:500, 1:200 | | Floor plan | From above, cut about 1 m above the floor | How are rooms arranged, where are walls, doors, windows, stairs? | 1:100, 1:50 | | Roof plan | From above, nothing cut | What is the roof shape, where does water go, what sits on the roof? | 1:100, 1:200 | | Elevation | Horizontal, flat on to one façade | What does each side look like, where are openings, what are the materials? | 1:100, 1:50 | | Section | Vertical cut through the building | How do floors stack, what are the heights, how is the roof built? | 1:100, 1:50 | | Detail | Enlarged cut or view | How do two parts actually join? | 1:20 to 1:1 | Scales differ between countries, so treat the numbers as a common range and not a rule. --- ## Floor plan: the layout of one level A floor plan is an imaginary horizontal cut through the building at roughly window-sill height. You remove everything above the cut and look down. What the cut passes through (walls, columns) is drawn heavily; what lies below (floor edges, stairs going down) is drawn with a thinner line. **What to look for when you read one:** - **Walls.** Thick lines are structure or party walls; thinner ones are partitions. Hatching or solid fill usually marks cut material. - **Openings.** A gap in a wall is a door or window. The arc next to a door shows its swing. Three thin parallel lines in an exterior wall usually mean glazing. - **Stairs.** An arrow shows the direction of travel, normally "up" from the level you are viewing. A diagonal break line means the stair continues beyond the cut. - **Rooms and labels.** Rooms are named and often given an area. Dimensions run as chain lines along the outside. - **Orientation.** A north arrow, usually in a corner, tells you how the plan sits on the site. A multi-storey building has one floor plan per level. Levels that repeat exactly, such as typical office floors, are drawn once and labelled as typical. If you are designing rather than reading, the floor plan is where most early decisions are made: how rooms connect, where circulation runs, where the stair goes. For how to turn a written brief into a first plan, see [From Brief to Floor Plan with AI](/blog/brief-to-floor-plan-concept-phase/). --- ## Site plan: the building on its land A site plan is a plan view of the whole plot. It shows the building outline (usually the ground-floor footprint or the roof outline), boundaries, setbacks, access roads, parking, paths, trees and neighbouring buildings. It also records levels and slopes where the ground is not flat. The site plan is what planning officers look at first, because it answers questions that do not depend on the interior at all: Does the building keep the required distance from the boundary? Where does the entrance sit relative to the street? How much of the plot is covered? Do not confuse it with a **location plan**, which is a small-scale map showing the plot within the street or district, or with a **masterplan**, which organises several buildings and open spaces at neighbourhood scale. For the multi-building case, see [AI Masterplan Generator for Multi-Building](/blog/ai-masterplan-generator/). --- ## Roof plan: the building seen from above A roof plan looks down at the roof without cutting anything. It shows ridges, hips and valleys, slopes (usually with arrows pointing downhill), gutters, roof openings, chimneys, plant and parapets. On a flat roof it also shows terraces, access hatches and the direction of drainage falls. Roof form is a large part of how a building reads from outside, so this drawing matters beyond waterproofing. A simple change, from a single-pitch roof to a pair of offset gables, shifts the whole character of the massing. It is also the drawing that most often gets skipped in early sketches and then causes trouble later. --- ## Elevation: what a façade looks like An elevation is a flat, perspective-free view of one outside face. Imagine standing far away with a very long lens: all lines that are vertical stay vertical, and all windows on the same wall keep their true proportions. A house normally has four elevations, named by compass direction or by their role (front, rear, left, right). Elevations show: - openings: window and door sizes, positions and rhythm; - materials: brick bond, timber boards, render, metal panels, usually by hatching or a note; - vertical levels: floor lines, parapet height, ridge height, often with level marks; - projections: balconies, canopies, bays, eaves overhangs. Because an elevation has no perspective, it is exact but not pictorial. It is the drawing to use when asking: Does the window pattern feel too busy? Is the proportion between solid wall and glass what we wanted? Is the façade too flat? --- ## Section: the building cut vertically A section slices the building from roof to foundation. It is the drawing that explains what plan and elevation cannot: heights. From a section you can read: - floor-to-floor and floor-to-ceiling heights; - stair geometry in profile; - double-height spaces, mezzanines, voids; - roof build-up and how the roof meets the wall; - ground levels, basements, steps at the entrance; - how the building steps with a sloping site. Sections are normally cut through the most informative places: the stair, a double-height room, the point where the roof is most complex. A plan carries a line with arrows to show where the section was taken and in which direction you look. A **longitudinal section** is cut along the long axis, a **cross section** across the short one. A cut through a wall, floor or roof at large scale is called a **wall section** and is where the construction is explained. --- ## Details: where the building is actually made Details are enlarged drawings of a junction: window head, threshold, eaves, balustrade fixing. In early design you do not need any. For permit and construction you need many. They are what a contractor builds from, which is why they sit outside the scope of any concept tool. The bridge from concept to this level is covered in [From AI Concept to Construction Drawings](/blog/from-ai-concept-to-construction-drawings/). --- ## "Architectural plan" versus "blueprint" versus "drawing set" A few words that are often swapped: - **Plan** on its own usually means floor plan. "Architectural plans" in the plural usually means the whole set. - **Blueprint** is the old term for a reproduced drawing, used loosely today for any construction drawing. - **Drawing set** is the correct term for the full package: cover sheet, site plan, plans, roof plan, elevations, sections, details, schedules. - **Schematic design** drawings are an early, simplified set: floor plans, a site plan, a couple of elevations and a section, made to agree on the idea before detail. - **Construction documents** are the full technical set used to price and build. When a client asks for "the plans", it is worth asking which of these they mean. --- ## Which drawing answers which question | If you are asking... | Open this drawing | |---|---| | Will it fit on the plot? | Site plan | | Is the kitchen next to the dining room? | Floor plan | | How do I get from the entrance to the bedrooms? | Floor plan | | What will the street side look like? | Elevation | | Is the ceiling high enough for a mezzanine? | Section | | What is the roof going to look like from above? | Roof plan | | How is the window sealed into the wall? | Detail | | How does the building step down the slope? | Section and site plan | --- ## A practical way to start a set For a house or small building, a sensible order is: 1. **Site plan sketch.** Boundaries, access, rough footprint. 2. **Ground-floor plan.** Entrance, living areas, stair position. 3. **Upper floors.** Align stairs, bathrooms and structural walls with the floor below. 4. **One section through the stair.** Check heights early. 5. **Four rough elevations.** Check that openings follow the plan and do not clash. 6. **Roof plan.** Settle the roof form after the plan is stable. The common mistakes are the same every time: stairs that do not line up between floors, windows in the elevation that do not exist in the plan, and a roof that cannot cover the footprint without awkward intersections. Drawing the section and elevations early catches most of them. --- ## Where AI helps and where it does not For concept work, a generated plan is useful as a starting layout to react to: room count, adjacency, circulation. It is schematic only: dimensions are approximate and nothing checks codes. The honest limits are laid out in [AI Floor Plans: How Accurate Are They?](/blog/ai-floor-plans-accuracy/), and options across tools in [Best AI Floor Plan Generators in 2026](/blog/best-ai-floor-plan-generators-2026/). In Nuit you can describe a plan in words, review the layout, and branch from it to try an alternative arrangement without losing the first one. Plans can be taken further into a 3D massing (see [From an AI Floor Plan to a 3D Model](/blog/ai-floor-plan-to-3d-model/)) and exported as DXF for an architect to continue in CAD ([What's Inside an AI-Generated DXF](/blog/dxf-layers-ai-export-what-architects-get/)). Sections, details and permit drawings stay with a licensed professional. --- ## Related reading - [House Architecture and Design: Roof, Massing, Plan and Materials](/blog/house-architecture-design-guide-form-roof-plan/) — the form decisions behind a house - [AI Architecture Glossary: 50 Terms](/blog/ai-architecture-glossary-50-terms/) — plan, section and the rest of the vocabulary in one place - [From Brief to Floor Plan with AI](/blog/brief-to-floor-plan-concept-phase/) — turning a written brief into a first layout - [AI Floor Plans: How Accurate Are They?](/blog/ai-floor-plans-accuracy/) — what generated plans get right and wrong - [What Architectural Style Is This?](/blog/what-architectural-style-is-this-identification-guide/) — reading a building from its form - [AI Site Feasibility and Massing](/blog/ai-site-feasibility-massing-vs-concept-design/) — the site plan stage in more depth