Tips for scaling rooms with interior wall thickness?

The topic title probably wasn’t the best, but I’m having a hard to concisely describing what I mean.

When I’m drawing building layouts in sketchup (not professionally, just for fun) I usually don’t add interior wall thickness until I’m satisfied with the room sizes, because I can’t find an easy way to scale a room without also changing its wall thickness. Is there a way around this that I just haven’t discovered?

You could probably select a wall and move it the required distance. That will change the size of the room without changing the thickness of the wall.


And here’s the Sketchup Campus course of the same process:

Manipulate Geometry

In the end there’s no shortcut for practice, but even if it feels wrong at first, creating “real” two-sided walls from the outset will never come back to bite you in Sketchup.

Yeah I get that. although I feel like before the room dimensions are known, it’s easier to just use rectangles, as there are much fewer operations to adjust the room size

Decide on your room sizes before you pull the walls up to 3D. Draw the plan such that the walls will have thickness when you do raise them.

Yeah pretty much what Dave said. You don’t have to limit yourself to rectangles. In the early stages keep it all flat and each space a group. Place them the wall thickness apart. Once your happy with the plan trace the exterior to form a face and offset it the thickness of your exterior walls, delete the inner face and make that a group. Then explode all your rooms and close the gaps until the faces between the rooms are created. Delete the inner faces and pull the whole thing up. Make that a group. You should be left with two groups one for exterior and one for interior walls.

rectangles was more of a shorthand for 2D shapes

With native tools, @DaveR shows how to do it. You have to be editing at the raw geometry level (i.e. enter a group if it’s grouped), and it’s one of the rare times I switch to parallel projection instead of perspective to get exactly the right selection.

When doing this task in PowerCADD, I use a Wild Tools plugin called move points, and I use it a LOT. For the same utility in SketchUp I’ve found the plugin, T2H Stretch by Area, to be very close. With it, you don’t have to be in the context of raw geometry, and your edit can effect more than one group at once.