Arched Window Headers

[Anonymous]

For years I have been having the same problem when using a window with an arched header, in 3D the external wall material floods into the arch between the bottom of the header and the top of the window. This does not look right and despite requesting a fix nothing has happened. Does anyone else have the same problem, if so is there an easy option?

[Anonymous]

Hi John,

Welcome to the forum!

Can you attach a screenshot of the problem? Maybe someone will have a solution once they see it. Also it would be very helpful to note what operating system you are on, what version of ArchiCAD are you using, and exactly which window is displaying the problem.

[Anonymous]

Yes, I am running OSX 10.6.6 on a Mac Pro and using ArchiCAD v14. but have had this problem with earlier versions. As you can see from the attached image, with arched head windows the brick material runs through to the window head, but in the real world this should be part of the window material. I have reported this to Graphisoft, as have my support company, but nothing is ever done about it.

[Anonymous]

So far I have only used arched headers with arch top windows or arched openings so there is no gap to fill between the top of the sash and the arch. Have you checked to be sure there is no parameter to substitute another material in the library part? I assume you are looking for a break metal or mortar/grout fill or such.

[Anonymous]

Matthew, I have looked in the parameters of the window library and can't find a way of changing the material at all, it is a mystery that seems to baffle me. Has anyone else encountered the same problem?

[Anonymous]

Hi John,

It looks like there needs to be a new adjustable arched top window where the arch extends right through to the inside of the wall, and the infill piece forms part of the frame and is the same thickness. I've attached a real-life example I've encountered in an old farmhouse recently. I presume this is similar to the type of construction you require.

I think it would also be useful to be able to adjust the radius of the top curve on the other arch topped windows too. Not all are semi-circular in reality.

One way you could work around the limitation at the moment is to cut away the incorrect piece of wall above the window with a hidden complex profiled beam SEOed away from the wall, and then manually add in another piece of shaped beam to infill the gap again with the correct materials applied.

[Anonymous]

For clarity, here's a diagram showing the shape of the beam to cut away the wall at the top.

Hope that helps for the moment. Let's hope they introduce a window that can do this automatically soon! I wouldn't have thought it was a massive job for GS to slightly adapt the wallhole, as the 'W Arched Top Opening 14' window can do this shape already just without the frame.

[Anonymous]

Peter that is exactly the situation, and as an interim measure your measure will work, however I have recently been converting a Victorian Listed Building with many arched head windows, and this method becomes tiresome, especially when amending a scheme. It became essential to keep the 'infill' arches on a separate layer and amend individually. As I have explained to Graphisoft, parameters should be embedded within the window object to sort this out, but no one is taking any notice. I would appreciate it if anyone else with this problem can add it to a wish list for Graphisoft, as I have been for 2 or 3 years now. many thanks for your reply.

[Anonymous]

What part(s) are you using? It might be a simple fix in the GDL.

[Anonymous]

I don't know exactly which one John was using, but I was using was one of the standard rectangular casement windows, with the masonry arched header set to brick. ('W2 Casement' specifically, but all the rectangular ones act the same.)