A set of house plans can look like a puzzle. Lines, numbers, symbols, notes in tiny print.
But plans follow rules. Once you learn a few of them, you can read most sets with confidence. That matters, because plans are what you approve, what a builder prices and what a surveyor assesses.
If you’ve never read a plan before, start here.
What’s in a typical set
A full set of plans is usually several sheets. The common ones are:
• a site plan
• floor plans
• elevations
• sections
• details and schedules
• notes
Each sheet shows the same building from a different angle. Read them together, not one at a time. A wall on the floor plan should match what you see on the elevation and the section.
1. Start with the site plan
The site plan shows your whole block from above. It includes the boundaries, the existing house, the new work, driveways, fences and anything else on the land.
Look for:
• the distances from the building to each boundary
• the north point, usually an arrow
• trees, easements and services
• where the new building sits compared with the old
This is the plan that matters most to councils and neighbours. It shows how the project fits the land.
2. Move to the floor plan
A floor plan is a view from above, as if the roof had been lifted off and you were looking down at a single level.
It shows walls, doors, windows, stairs and room layouts. Rooms are usually labelled. Dimensions run along the edges.
Walk through the plan as if you were inside the house. Start at the front door. Go to the kitchen. Go to the bedrooms. Ask:
• Does the flow make sense?
• Is there enough room to move furniture in?
• Are doors swinging into each other?
• Where does the light come from?
This is the best time to find a problem. Changing a drawing is easy. Changing a house is not.
3. Understand the scale
Plans are drawn smaller than real life. The scale tells you how much smaller.
A common scale is 1:100. That means 1 millimetre on the paper equals 100 millimetres in real life. So a line 30 millimetres long on the page is a 3-metre wall.
Other scales you’ll see are 1:50 for more detail and 1:200 for bigger areas. The scale is written on each sheet, usually near the title.
Don’t measure plans with a ruler and expect perfect results. Printed drawings can shrink or stretch. Use the written dimensions instead.
4. Read the dimensions
Dimensions are the numbers along walls and between features. They’re almost always in millimetres.
There are usually two kinds:
• Overall dimensions. The total length and width of a wall or room.
• Internal dimensions. The sizes between specific features, like windows and doors.
Check that a room’s internal dimensions are big enough for what you plan to put in it. A bedroom that’s 3 metres wide may look fine on paper but feel tight with a bed and two wardrobes.
5. Learn the common symbols
Plans use symbols so they don’t have to spell everything out. You’ll quickly get used to the common ones.
• A door shows as a gap in the wall with a curved line showing which way it swings.
• A window shows as thin parallel lines inside the wall thickness.
• Stairs show as a series of lines with an arrow showing the direction up.
• Walls are drawn thicker than other lines. Some are shaded or hatched to show different materials.
• Kitchen and bathroom fixtures usually appear as simple outlines.
Most plans include a legend or key. If you see a symbol you don’t know, check there first.
6. Look at the elevations
Elevations show the outside of the building from each side. They’re usually labelled by compass direction or by position, such as front, rear and side.
They show the shape of the roof, the height of walls, window sizes and external materials.
Compare each elevation with the floor plan. The windows on the plan should match the windows on the elevation. Check the roof pitch and overall height too. Many councils limit how tall a building can be.
7. Study the sections
A section is a slice through the building, as if you cut it with a giant knife and looked at the inside.
It shows floor levels, ceiling heights, roof structure and how the building sits on the ground. It’s where you’ll see things that don’t show up on a floor plan, like a step between rooms or a sloping ceiling.
Look for the ceiling height. It affects how spacious a room feels. Look for how the building meets the land, especially on a sloping block.
8. Read the notes and schedules
Notes are the text on the plans. They say what materials to use, how things connect and what standards apply.
Schedules are tables, usually listing windows, doors and finishes. They give sizes, types and sometimes colours.
Read them. Notes are where builders and surveyors find important details. A plan with no notes is a warning sign. It may be missing the information that stops disputes later.
A good way to read a set
Try this order:
• Start with the site plan and check it matches your block.
• Look at the floor plans and walk through each room.
• Check the elevations against what you expect to see from the street.
• Look at the sections for heights and levels.
• Read the notes and schedules last.
Mark anything you don’t understand. Write your questions directly on a printed copy.
Questions to ask your drafter
Don’t be shy about asking. Good drafters expect questions and are happy to walk you through the plans.
• Does this layout meet the setbacks and height limits?
• Where are the load-bearing walls?
• How does the new work connect to the existing house?
• What materials are assumed in this drawing?
• What’s not shown here that I should know about?
Ask for a walk-through before you sign off. Better still, ask for 3D views or a model if they offer them. Many people understand a space better in three dimensions.
Don’t sign off too early
Once you approve the plans, they go to the surveyor and builder. Changes after that point cost more.
If you’re unsure, take them home for a week. Show them to someone you trust. Imagine living in each room.
When you’re ready to have plans drawn, drafting services Melbourne homeowners trust can produce a clear, accurate set and take you through it page by page.
Reading plans is a skill. Like most skills, it gets easier each time you do it.
