topic Re: Creating a roof to sit on walls at different heights in Modeling

Creating a roof to sit on walls at different heights

PHIL7 — Tue, 09 May 2023 13:04:35 GMT

Hey I have a design of a small home on a sloping site where the floor and walls step up about 1m on the high side of the site. I want to create a single roof structure that covers both sides of the home.

How can I, or is it even possible, to set the rotate line (the blue roof line) so that it steps up in height from the top on the walls on one side to the higher walls on the other? I have the step up set to a different story level if that makes any difference...?

I have tried to build a seperate roof on each side, crop them into single planes and stretch the planes out to get something that Im after but this gets pretty messy.

Any ideas?

Thanks 🙂

Re: Creating a roof to sit on walls at different heights

Lingwisyer — Thu, 08 Dec 2022 01:00:55 GMT

Can you show a plan of the roof you are wanting to create?

Re: Creating a roof to sit on walls at different heights

Barry Kelly — Thu, 08 Dec 2022 01:14:55 GMT

For a single plane roof you can rotate the angle of the pivot (pitching) line if you know where it should be.

If not, and you probably won't, you can place a roof plane in 3D and nominate 3 height points that will give you the plane you want - you can edit the perimeter shape further if you need.

Here is one post I found that might explain it.

https://community.graphisoft.com/t5/Design-forum/Create-sloped-butterfly-roof/m-p/277927

Barry.

Re: Creating a roof to sit on walls at different heights

Barry Kelly — Thu, 08 Dec 2022 01:28:08 GMT

But now looking at your image (I should have done that first), it looks like you just need to trim the roofs together.

Separate roofs on each box (area) at the required heightand trim them.

Problem is this will create valleys where you don't want them.

So convert them to single roof planes, or model them with single roof planes in the first place.

The pivot line is in the correct position and height above each wall is correct.

Then you can extend the internal edges and trim each plan to the other adjacent planes.

You will probably need to add extra nodes to the edges as you trim them otherwise you will find it won't work.

You should be able to see in the 3D model where you need to ad nodes to the internal edges - just follow the hips and valleys up from the corners until you see where the planes intersect or divert from each other.

that is where you need to add a node to create a new hip, valley or ridge.

Or if you map out the hips and valleys in plan with lines (not sure if you remember the old days of manually drawing a roof with lines), you can just stretch the edges of each roof plane to match those lines.

Barry.

Re: Creating a roof to sit on walls at different heights

PHIL7 — Fri, 16 Dec 2022 22:09:28 GMT

Hi Barry thanks for your reply.

I did exactly as you said and it worked a treat. I was having trouble to start with because some of my walls were not perfectly square and when I extended up the roof planes they did not align.

Phil