Draw the base area by plan

To draw the floor area, you can import a floor plan and use it as a template. First scale the floor plan to the correct size and then draw the contour with the line tool.

If a PDF contains vector data, these are stored on a separate layer (see section result on page Import PDF).
You can then also snap to the floor plan lines and thus achieve exact results.

Steps

Click Top in the Views toolbar.
The view changes and in the top left corner the text Top is displayed.
Select a PDF file and click Import or double-click on a PDF file.
The contents of the PDF file are displayed in SketchUp.
Switch off the layer with the image data (in the example Layer_image_1) and check whether the layer with the vector data (in the example Layer_1) is switched on.
Zoom an area where you know the length of a specific distance.
Select the Tape Measure Tool in the Getting started bar.
A Tape measure and a violet dot with the icon --+ is displayed at the cursor.
Press the Ctrl key.
The guide line icon --+ is not displayed at the cursor any more.
You switched to the Measure mode.
Snap to the 1st end point of the known distance.
Snap to the 2nd end point of the known distance.
The distance you have marked is measured in the current scaling.
Type the correct length and press [Enter].
A dialog is displayed.
Click Yes.
The floor plan is resized.
Select the Line tool in the Getting started bar.
A Pencil is displayed at the cursor.
Trace the outsides with the Line tool by snapping and clicking all corner points one after the other.Z
Close the base area by setting the last point on the start point.
Press [Space].
The spacebar ends the line tool and activates the select tool.

Result

You traced the base area from a floor plan true to scale.
Define the building height in the next step.