To read a plan, look at the scale and overall dimensions first, then find missing lengths by subtraction, then describe how the rooms connect. Doing them in this order helps you avoid careless mistakes.
This lesson belongs to the wider SPM subjects and learning resources section. The plan below is original and described in words.
What should you check first on a plan?
Check the scale, the unit and whether dimensions are internal or external. A plan in millimetres read as metres gives an answer 1 000 times too large.
Then find the overall length and width. Every smaller dimension must fit inside these.
Worked example: a small house plan
An original plan shows a rectangular house with an overall width of 9 000 mm and depth of 6 000 mm. Along the width, reading left to right, there is a bedroom of 3 500 mm, a hall of 1 200 mm and a living room whose width is not shown. The plan uses external dimensions.
Missing width. Subtract the known parts from the total: 9 000 − 3 500 − 1 200 = 4 300 mm.
Check. Add them back: 3 500 + 1 200 + 4 300 = 9 000 mm, which matches the overall width.
Area of the living room. If the depth is 6 000 mm, the area is 4 300 × 6 000 = 25 800 000 mm², which is 25.8 m² because 1 m² is 1 000 000 mm².
Explaining relationships
A relationship answer needs a pairing and a reason. In this plan the hall sits between the bedroom and the living room, so it acts as a link and keeps bedroom activity away from the main living space.
If the living room window faces the front, say what that does, for example letting daylight into the room used most during the day. The reason is what turns an observation into an explanation.
The mistake that loses marks
The usual error is to read off a dimension and stop. “The living room is next to the hall” is true, but it earns few marks.
The second error is skipping the addition check. If you find 4 300 mm and move on, you will not notice an arithmetic slip that leaves the parts short of the total.
Describing a conceptual build sequence
Some questions ask for the order of construction at concept level. A sensible order is setting out the plan, preparing the ground, laying the foundation, raising the walls, then adding the roof and finishing.
Explain why each stage comes before the next, for example that walls need a foundation that can carry them. Site safety, tools and hands-on steps are taught by your school teacher, not from a web page.
Check yourself
A second original plan has an overall width of 8 400 mm. A kitchen of 2 800 mm and a dining area of 3 100 mm sit side by side, and a store fills the rest. Find the store width and explain in one sentence why the check works.
Answer
Store width = 8 400 − 2 800 − 3 100 = 2 500 mm.
Check: 2 800 + 3 100 + 2 500 = 8 400 mm. The check works because the three spaces fill the width exactly, so their sum must equal the overall dimension.
What to study next
Use the structured-answer self-review tool to test whether your explanation includes a pairing and a reason.
For a teacher to work through more plans with you, see online one-to-one Domestic Construction tuition or the one-hour trial class (from RM50). Site and workshop work stay with your school.