topic Re: How to remove the outlines between 2 overlapping roofs? in Modeling

How to remove the outlines between 2 overlapping roofs?

SomeGuy — Sat, 14 Mar 2026 04:14:49 GMT

In the process of learning, thank you for any patience required.
So there was an instance that required a thicker section of a roof for insulation. The way they did it was to make a copy of the roof, size it for the indoors part, edit the thickness and reposition against the original roof, and then they did a solid element operation > subtraction with upward extrusion. Hopefully I didn't miss a step, had to reproduce later on my own.
But effectively got the windows to not look strange and the roof is in position, but this generates outlines between the 2 where simply removing outlines will not make it any better. Is there anything that can help here, or is this version of the software they use(Archicad23) too old for that?

Operating system used: Windows 11

Re: How to remove the outlines between 2 overlapping roofs?

Durval — Sun, 15 Mar 2026 15:45:53 GMT

It would help if you showed us a section, but if I correctly understood your issue, you shouldn’t use a Solid Element Operation in this case (actually, you should avoid it whenever you can get the same shapes by regular modelling).
You can create a hole in the bigger roof by simply selecting it and drawing a new outline. The new outline will be the contour of the roof hole.
But instead of making a hole, in your case I would probably create a new Roof element with only the insulation layers placed below the other Roof with tiles/panels, without creating any hole in it.

Re: How to remove the outlines between 2 overlapping roofs?

cuba — Mon, 16 Mar 2026 05:39:05 GMT

Don't use solid element operations for the substractrion, just make a hole in the roof by selection it and the tool and draw a rectangle.

Or make the whole roof with insulation en make a second roof to cut the the insulation of, the second roof won't touch the windows and will be displayed ok.

Re: How to remove the outlines between 2 overlapping roofs?

SomeGuy — Mon, 16 Mar 2026 06:03:57 GMT

Without any holes in it, wouldn't the windows look questionable in 3D?
Here's the cut, hopefully makes it a bit clearer what is currently going on.

Re: How to remove the outlines between 2 overlapping roofs?

MitchD — Thu, 19 Mar 2026 21:13:56 GMT

merging the roofs should remove any unnecessary lines

Re: How to remove the outlines between 2 overlapping roofs?

Lingwisyer — Mon, 16 Mar 2026 06:48:38 GMT

Your Skylights will be in the thicker roof, so you will see the penetration in section. The thicker roof sits within a cutout in the thinner roof, no SEO required. OR, if you model it as Durval is suggesting, as a roof with an underlay of insulation, you can use the opening tool to cut the insulation inline with the Skylight.

Ling.