Trimming/SEO to roof

[Florin Luca]

I wonder if anyone has come across something like this. I have two roofs that I trimmed to each other. Then I tried to trim the dormer walls to the two roofs and here is what stumbled upon. It could be that it has always worked this way, bc until now I only used SEO to trim my walls to roofs.

The dormer wall on the right, I had it trimmed at the bottom to the larger roof, which worked fine, but when I tried to trim the top to the dormer roof, nothing happens. Not only that, but when I tried to SEO to the dormer roof, still nothing.

The dormer wall on the left was SEO-ed to each roofs and it cleaned out nicely.

As an aside, I found that using beams for side dormer walls is more accurately shown on plans than walls, as the walls are shown to their full length, as though untrimmed, regardless of the FPCP height.

Question is, has this always been "working" like this or it is a bug? As I said, haven't used trim much before so I can't tell.

Operating system used: Mac Intel-based 26 Tahoe

[Charlie64]

Hi,

I am not sure from this pictures, but could it be possible that you trimmed the wall down? Like, if you rotate the view, would the wall be visible only up from the dormer roof?

Usually archicad asks you if you want to trim up or down and it selects depending where you click (it is visible in red).

Hope that helps, if not, can you share more screenshots from different angles?

[Florin Luca]

Thank you for answering, I was beginning to feel left out! 🙂

Yes, the wall in the background has been trimmed down by the larger roof bc I didn't want the dormer side wall to come down into the attic; it should stop at the roof (it asked the direction, as you said), but the issue is that it cannot be trimmed/SEO-ed up by the dormer roof, so that the upper part doesn't stick out. That's why I left it sticking out. Wall in the foreground has been SEO-ed up and down by both roofs.

Again, the issue is that you can only trim/SEO once, in one direction, even if you use different roofs. Bear in mind my two roofs have been trimmed to each other so that might have something to do with it.

So I want to know if this is how it works or it is a bug.

[Barry Kelly]

Trimming to both an upper and lower roof should work just fine.

"Trimming' a roof uses the trimming body of the roof.

For a roof this can be set to 'Pivot line down' or 'Contours down'

Your dormer roof may be set to pivot lines down and the wall may be outside of the pivot line, so it will not trim to that upper roof.

There is an on-screen option to see the trimming bodies in 3D.

Trimming also uses the building material strengths, so you might see the top of the wall level with the top of the roof if the wall materials are stronger than the roof.

You want the roof materials to be stronger.

SEO works with upward or downward extrusion of the roof mass, so the wall will never poke through.

But if you already have a trim in effect, this will cause a hole in the roof where the wall is, and no matter how hard you try, the SEO will not work as there is no roof where the hole is to SEO to.

So be sure to use one or the other.

Personally I prefer SEO as it cuts to the top/bottom surface of the roof, does not rely on building material strengths and does not use the trimming body.

But both 'trimming' (connecting) and SEO have their place.

Barry.

[Florin Luca]

Hi Barry,

Thank you, yes I know about all that and I have only been using SEO, but I thought I mix it up a bit. Actually, I found roofs, such as in my configuration, clean up nicer with Trim then with SEO (bc of overhangs, usually SEO is not working for roofs, so I need to use a morph, and then hide it).

What I found puzzling here (and I can move on, as I have workarounds, but it bugs me as I want to understand what's going on) is that once trimmed by the main roof, I cannot SEO the top of the wall by the dormer.  Yes, I discovered that my dormer pivot lines are outside of the wall, so it won't trim no matter what.  Still, you tink it should SEO the top though. If I only use SEO for both bottom and top, no trouble at all.

If you have time, I attached the file, set to generic materials, so no priority conflicts. The two roofs are already trimmed to each other. If you can play around with it, you'll see what I mean.

Thank you,

Florin

[Barry Kelly]

Because your main roof and the dormer roof are connected, when you trim the wall to the main roof, it creates a hole in the dormer roof as well.

Select the dormer roof and you will see the hole.

Because there is a hole in the roof the SEO will have no effect - there is no roof passing through the wall to trim to.

It seems that the connect > trim to roof does not work either as the roofs act as one when connected.

So, 2 solutions I can think of.

Only use SEO and subtract with downward extrusion to the lower roof and with upward extrusion to the dormer roof (the roofs can stay trimmed to each other).

Or don't connect the roofs, but you will have to manually cut a hole in the lower roof that is the shape of your dormer.

Now you can connect > trim to each roof.

Barry.