Question

why we refer to the plan when we want to know the measurement of a room in a building​

Answer 1

Explanation:

Buyers use floor-plans so that they can assess whether the property meets their needs. The dimensions allow potential purchasers to see how their furniture would fit in the space so they can picture the property as their own.

Answer 2

It is because to adjust our ideas accord to the measurement of the room....

if we measure and starts to plan it must be difficult...