What is the difference between a plan, an elevation and a section?

A plan is a view looking down from above, showing the layout of a floor. An elevation is a flat, head-on view of an external face of the building, showing what it looks like from outside. A section is a vertical cut through the building, showing heights, the roof structure and how floors are built. Together they describe the same building from three different directions — you read them alongside each other, not in isolation.

What does the scale on a drawing mean?

Scale is the ratio between the drawing and real life. A scale of 1:100 means one centimetre on the drawing represents one metre on site, so the drawing is one-hundredth of full size. Knowing the scale lets you understand real distances, but you should always use the figured (written) dimensions rather than measuring off the paper — printing and photocopying can distort the scale slightly.

Why should I not just measure dimensions off the drawing?

Printed and PDF drawings can be scaled up or down when produced, so measuring with a ruler can give a misleading figure. That is why drawings carry written dimensions for anything important. The rule on every professional drawing is "do not scale" — use the figured dimensions, and if a dimension you need is missing, ask the designer rather than guessing.

What is a title block and why does it matter?

The title block is the panel, usually in the bottom corner, that records the project, the drawing title and number, the scale, the date and the revision. It matters because construction projects generate many versions of the same drawing as the design develops. Always check the revision and date so you and your builder are working from the latest issue — building from a superseded drawing is a classic and costly mistake.

Do I need to understand drawings if RCB is doing design and build?

You do not need to read them like a professional, but understanding the basics helps you make confident decisions and spot anything that does not match your expectations early. With RCB's design-and-build service we walk you through your drawings in plain English, explain what each one shows, and make sure you are happy before anything is built. Contact us to talk through your project.

How to Read Architectural Drawings: A Homeowner's Guide

How to Read Architectural Drawings

A set of architectural drawings can look like a wall of lines, numbers and symbols. But once you understand what each drawing is for and how to read the basics, the whole picture comes together — and you can make confident decisions about your own project. This is a homeowner's guide, not an architecture lesson.

Why It Helps to Understand Your Drawings

Drawings are the language a project is designed and built in. They are how your ideas become a planning application, how a builder prices the work, and how the structure actually gets built. You do not need to read them like a professional — but understanding the basics means you can check the design matches what you asked for, spot problems early, and approve drawings with confidence rather than crossing your fingers.

The most expensive misunderstandings happen when a homeowner signs off a drawing they did not really understand. A little knowledge removes that risk.

The Main Types of Drawing

A typical project set includes several drawing types, each describing the building in a different way:

Floor plans

A view looking straight down from above, as if the roof were removed, showing the layout of each floor — walls, rooms, doors, windows, stairs and fixtures. This is the drawing most people find easiest to read and where you check that the layout works for how you live.

Elevations

A flat, head-on view of each external face of the building — front, rear and sides. Elevations show what the finished building looks like from outside: window positions, materials, rooflines and heights. They are how planners assess the visual impact of your project.

Sections

A cut-through view, as if the building were sliced vertically, showing floor-to-ceiling heights, roof pitch, foundations and how floors and the roof are constructed. Sections reveal the things plans and elevations cannot — what is happening inside the structure.

Site / location plans

A wider view showing your building in relation to its plot, boundaries, neighbouring properties and the road. Location plans (usually 1:1250 or 1:2500) are required for planning applications; block plans (1:500 or 1:200) show the site in more detail.

Detail drawings

Large-scale close-ups of specific junctions — how a wall meets the roof, how a threshold is built, how insulation is detailed. These are construction-stage drawings that tell the builder exactly how a tricky part is put together.

Structural drawings

Produced by a structural engineer, these show beams, columns, foundations and steel or timber sizes, with calculations. They sit alongside the architect's drawings and are essential for Building Regulations and the build itself.

Understanding Scale

Drawings are produced to scale — a fixed ratio between the drawing and real life. Knowing the scale lets you understand real sizes at a glance:

1:100 — 1cm on the drawing equals 1 metre in real life. Common for floor plans and elevations.
1:50 — a more detailed plan; 2cm equals 1 metre. Used where more detail is needed.
1:20 — close-up detail, often for kitchens, bathrooms and joinery.
1:1250 — location plans for planning, showing the wider context.
1:5 / 1:1 — construction details and full-size templates for specific elements.

Always use the written (figured) dimensions for anything important. Never measure critical sizes off a printed drawing — printing can distort the scale. Professional drawings carry the note “do not scale” for exactly this reason.

Common Symbols and What They Mean

Once you can read a handful of conventions, a floor plan becomes far easier to understand:

A thick lineA wall that is cut through by the plan — usually a solid structural wall.

A thin lineAn edge or object below the cut, such as a worktop or a change in floor level.

A gap with a quarter-circle arcA door, with the arc showing the direction it swings.

A break in the wall with thin parallel linesA window opening.

Dashed linesSomething hidden or above the cut line — often a beam, a roof overhang or a wall removed.

A circle with a number or letterA reference tag pointing to a detail drawing or a room/door schedule.

A line with arrows and a numberA dimension — the measured distance between two points, usually in millimetres.

North arrowThe orientation of the building, important for light and for reading the site in context.

A Checklist for Reviewing Your Drawings

When a set of drawings lands in your inbox, work through this before you approve them:

Read the title block — drawing number, scale, revision and date — and check you have the latest version
Confirm the scale before you measure anything off the drawing
Match the floor plan to the elevations and sections — they describe the same building from different angles
Check dimensions are stated; never scale critical measurements off a printed drawing if a figured dimension exists
Look for the revision cloud or notes that show what has changed since the last issue
Cross-reference detail tags to the detail sheets
Check window and door schedules against the plan
Ask your designer to explain anything that is unclear — that is part of their job

We Walk You Through Every Drawing

With RCB's design-and-build service we do not just hand you a set of plans — we sit down and explain them in plain English, so you understand exactly what is being built before a single brick is laid.

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