Before creating walls in SketchUp it’s necessary to have the dimensions of the room or house first. This can be either in the form of an Autocad drawing, which can be imported into the Pro version of SketchUp. If you only have the free Make version you can simply use a hand-drawn as sketch as a reference.
Before modeling make sure that Layer 0 is the active layer since this is where we do most of our modeling. Now select the Rectangle tool (or hot R on the keyboard) and trace the plan outline of the building, creating a series of rectangles. The order doesn’t matter. If you have imported a CAD floorplan now make floorplan layer invisible in order to see the new rectangles more clearly. With the Eraser tool erase the inner lines, resulting in the full outline, or footprint, of the building. If you were creating a simple massing model for a larger site you would now simply use the Push/Pull tool to extrude the rectangles upward in the Blue axis by the wall height, for example 2800mm. To do this select the Push/Pull tool, select the face or faces you wish to extrude and type in 2800 into the Measurements window on the bottom right of the screen. Alternatively you can type 2.8 followed by m for metres – this overrides the millimeters of the general model units.
However we may want a more detailed model with wall thicknesses. For this we need to turn on Floorplan layer and use the Offset tool (F) to thicken the walls, either using the CAD plan as a reference, or using the Tape Measure tool (T) to first measure the wall thickness. This could be 270mm for double-brick walls, or 110mm for single-brick walls. To offset select the Offset tool, click on the rectangles of the footprint, then enter the wall thickness value and hit Enter.
Now we measure the wall height from the elevation drawing of the CAD file, for example 2800mm, or 2.8m. Select the Push/Pull tool, click on the new wall thickness face and pull upwards by 2800, resulting in the exterior walls of the building. Next it’s important to triple-click the walls with the Select tool to select all associated edges and faces, then right-click to Make Group. This will become important later if we need to hide or move the walls object. If we forget to do so, the walls can stretch instead of move, and become “stuck” to other objects.
Now it’s good house-keeping to create a new layer for the External Walls, then right-click on the walls and open the Entity Info panel to move the walls to their own layer. In this way we can make this layer invisible if necessary. We would now repeat the process for the internal walls, first selecting and deleting any infill rectangles. Then Push/Pull these walls also upward by 2800. Make these a group also and create a layer for them too.
Note that unsightly seams may appear where exterior and interior walls meet. To hide these first double-click to enter the Exterior wall group, select the line and right-click to Hide. Note that you’ll have to repeat this for the same seam in the Interior wall group. It’s not possible to delete these lines since lines define surface faces in SketchUp, and to delete an edge will result in the associated face disappearing also.
Creating walls in SketchUp is a simple process if you follow a logical workflow like this one.