Extension to force being true to 2D plane?



Hi Guys & Gals,

I know I’m taking days longer to model my house designs for clients than I should. :sweat: This is one of the culprits and any advice (beyond staying true to axis, which I am apparently inept at :drooling_face:) or link to an extension that may force 2D results, when designing in plan view, is greatly appreciated!!! :clap:

No matter how careful I try to be… (pre-selecting red/green/blue axis, double-checking closures, etc.), I keep ending up with faceted planes throughout my drawing. It even happens somehow to planes that where already perfect (like my boundary walls… which I could apply material to in one gesture early on… but then have to find all the triangles to do likewise in that same skin later on).

This uploaded example is with those corruptions shown. I can hide them easy enough. But the wanna-be Master knows what lurks in the closets of his craft! Thx in advance for any wizardly advice! :mage::woman_mage:



Download extrude tools (by TIG), then vector extrude the edges you want down through a plane. Intersect, then it’s 2d instead of 3d.

To design in 2d, get really good at inferencing. Which is where you use the arrow keys to keep lines on axis, shift to keep on plane, or whatever.


Have you checked out Dibac for SketchUp?
They have a demo. See: dibac.com


It’s a workflow thing. If you insist on working in plan view, then first draw a really big rectangle on the red/green plane (or any other plane you want to), then double click to select the rectangular face and it’s edges, then make it a group or component.

NOW when you’re drawing in plan view (and presumably parallel perspective) pause with your cursor on the face before beginning to draw. That will indicate that you want to draw on the rectangle to SketchUp’s inference engine.


You haven’t uploaded the drawing so it’s difficult to know everything that is going on. The most likely thing causing all those lines is that you are not grouping things early enough. That may also mean you are not using layers properly either. When designing houses (as I do), most people would have separate groups or components for things like walls, floors, windows, doors, furniture, roofs, and so on. So, you start by drawing your element, say the ground floor, in Layer 0 (you should ALWAYS draw in Layer 0 and no other). When that is done, group it and assign it to a new layer, appropriately named. If it’s something that repeats, like a door, make it a component so that any changes will be repeated across the board.

The inherent stickiness of SU geometry is one of its great strengths, allowing you to extrude shapes, etc. But it is also its greatest weakness if you do not know how to control it. It’s a rookie error and one I made constantly when I started.


Making raw geometry into a Component isolates it from other geometry.
Thus, the geometry inside a Component is protected from inadvertent alteration.

From the very beginning, focus on organizing logical parts of the model into Components.
Build, say, the exterior walls. Make them a Component and then Lock it.

Then build the next logical part, most likely, the interior walls. Make them a Component and then Lock it.
And so on, until the model is complete.

When finished, a properly built model is an assembly of components with no raw geometry left unprotected in the model space.

See this brief training video:


It’s not obvious what you mean by this. The image you uploaded shows a weird combination of a 2D plan and 3d elements like windows and sanitary ware (I expect you downloaded those from the Extension Warehouse).

I sometimes work in 2D when I just need to do some simple space planning. I have made myself a library of 2D components for that purpose. I keep them in a separate folder from my 3D components.

When working in 2D, you would normally use a Top View only and have Parallel Projection switched on. As @sjdorst has pointed out, it can be helpful to start with a rectangle on which to start drawing as that makes it easier to make sure you are only drawing in 2D with no Z dimension. You may also find the extension 2D Tools useful.


To fix up your model I would perhaps take a look at this video.

Though I must admit that I really would want a “look to Z & 0”-plugin developed by someone for all the times when I just want to draw something in 2D.


Hi George.

Thx for the feedback! I wasn’t aware you could “lock” anything!

I also watched the link you provided and learned more about component library management; that also helped.

Thx again!

Billy Ream
Florence | The Shoals


Hi Simon,

Thank you for your feedback. You are right. I wasn’t making groups and components early enough!

I’m redrawing this house from scratch and making everything conceivable into groups… right down to the basement slab’s expansion and control joints (separate from slab itself).

A bonus discovery in doing that is that take-offs (like overall slab area) have become easier. So, my logic now is to group things both for geometric isolation and also for facilitating cost estimating.


Billy Ream
Florence | The Shoals


Sounds good. however, I have found that it is possible to over-group, especially if you end up with multi-nesting (groups within groups). It can make navigation difficult as well as editing. If you haven’t discovered the joys of Outliner you should. I ignored it for a long time thinking it was an unnecessary frill, but it really helps finding your way around a drawing, especially if it is at all complicated.

One other extension you might find useful now you have become group-tastic is Stretch by Area. It allows you to choose points that lie in different groups so that you can move them in one operation. Normally, you have to go into each group and do it laboriously one by one. For reasons I don’t understand it doesn’t work 100% of the time but it works often enough to be useful.


Adding to @simoncbevans reply, if you assign instance names to your groups (and component instances) the outliner will show those. If you don’t do so, it will display “Group” for each group and an auto-generated name such as “Component#12” for each component, making the outliner almost useless! Yes, some speed-freak modelers object to the delay (and mental effort) required to assign names to things, but it will help greatly when subsequently working with your model.


I would second that. One of the great things about Outliner is that if you select a group/component in the model, it will be highlighted in Outliner. But the reverse is also true: select something in Outliner and it will be highlighted in the model.

Some very experienced people here only ever use Components. If you do that, it will encourage you to name each one (though you can accept the default for speed). If you accidentally erase a component instance in the model, it will still be in the In Model group of components so you can always get it back. That isn’t true of Groups.


I have planes set up on my template as you suggest. They are on their own layer and can be turned off when they are in the way. It’s helped me a lot to keep items on planes. I have a template for feet and inches and delete the text once i get started. I also have a 3d centerline on the template that i drop on the center of circles and shafts.


@kcpilotpat, what tread does this answer belong to?