Got a minute? We appreciate your feedback:

Graphisoft Learn survey
About Archicad's design tools, element connections, modeling concepts, etc.

Oh that roof!


Most people on the forums, ask questions and ask for help and advice. But I decided to blog about events and work related directly to the Archicad program in my work. About the pros and cons of working with client projects.

Today I want to touch upon such a topic as the stages of the project: the existing building, the demolished part of the building, and the proposed building. The client provided me with the drawings of the existing building (floor and facade plans) in the form of a PDF file and also the proposed redevelopment. He needed a 3D model of the Archicad as the drawings were only in 2D PDF format. But the main problem was that the existing roof had to be partially demolished, which added to the complexity in the construction of the proposed one since the second floor was quite changed from the outside and some problems of displaying the state of the model followed from this. Plus, the main problem was the fact that there were only facade plans where you could see how the roof was arranged, there was no separate view from above. To somehow understand the type of roof, I had to look for the building on the maps. And so began my journey through Google Maps in search of the very roof and the general view of the building in real life. Unfortunately, the customer did not provide photos of the building, so when I found the house on the map, I was very happy!

Once the existing building was completed, it was a difficult task to make the new roof extensions (the roof was complex and consisted of 10 45-degree pitches) as all the walls were adjacent to the previous height of the old roof section and the wall height had already been trimmed with the Solid Element. Fortunately, this problem was only on one side of the facade, and since time was limited, it was decided to close the holes in an easy and fast way, such as adding new pieces of walls and using the Solid Element function to cut under the old walls and new roof. Happiness knew no bounds when switching the display of the existing building to the proposed one, and everything looked perfect! As a result, the new roof had 15 slopes and part of the demolish was correctly displayed on the facades and plans.

I named this type of work: Frankenstein. When you have a project for a very old building with its existing problems of layout and elements, you need to do everything cleanly and beautifully for the client. Plus, I was very lucky with the Team4Bim team, my colleagues will always come to the rescue and help out a lot with advice.

I would like in Archicad there would be a function for selecting the display of the Solid Element individually for each state of the project. This is of course easier said than done, but this is what I would like to see in Archicad and I think it will make the job easier for many.


Have you ever had such situations? If so, please share your experience!

Always in creativity


Doing a lot of renovation work myself I always find myself wishing for the same SEO ability as you.

Often enough the SEO needs to be applied at the "new/proposed" stage, which leads me to just duplicate the geometry and have the SEO to be used on one twin, witch each of them pinned. Sometimes you can get away with using an BMAT intersection ("strong air"!), but most of the times not so much.

In any case you'll have a lot of trouble and it will break easily. It's just so fragile! And God forbid you'll need to show variants or have to do re-planning....


Lucas Becker | AC 27 on Mac | Editor at SelfGDL | Developer of the GDL plugin for Sublime Text |
«Furthermore, I consider that Carth... yearly releases must be destroyed»

Yes, working with change and alternatives in AC is a chore and the usual solution of creating elements ad hoc is obviously not compatible with the development of CAD/BIM. Compared to other issues such as lacking type/instance and references/constraints which actually is a question of catching up with the competition a intuitive - an intuitive and effective way to handle change and alternative designs would be a leap in front of the competition. My wished approach to change and alternative design is outlined here.

Start a new conversation!

Still looking?

Browse more topics

Back to forum

See latest solutions

Accepted solutions

Start a new discussion!