Roof Deck with Roof Tool or Slab Tool

[rmcelvain.103137]

Hey, is it better to use the SLAB tool for a roof or should I use the ROOF tool from the architectural tab?

thanks,

[David Harrington]

I tend to use the Slab tool typically. I perhaps might use the Roof element if I had a hip/gable type roof though.

[rmcelvain.103137]

David,

It's a sloped roof that I need to attach my structure to. I've just posted a question in the Building forum to get some advice on that part......I'm not so good at making roofs yet!

Thanks for the reply,

[David Harrington]

Yep, I would still use the Slab object type. I would create several triangular shaped slabs, each with a slope arrow controlling the slope. Remember that there are no 'warped' slabs or roofs in Revit.

Then I would reference planes for the roof beams to attach to.

[Tom Weir]

Hi,
If it is a roof I use the roof function. There are a few added parameters for end conditions that the slab function does not have.
Like David I would use triangle shapes for the corners. For the warped portions (the inner diamond) you can use a blended solid. That is your only hope for now for that part.

Tom Weir
Los Angeles

[rmcelvain.103137]

Don't you find that if you create the warped portion and then place the beams where they actually occur that the beams protrude into the roof?

I've been playing with it today and the most accurate way I've found is a recommend from Scott Brown (LINK TO SIMILAR THREAD IN REVIT BUILDING FORUM); (http://forums.augi.com/showthread.php?t=33603#post278074) he mentioned using the TOPO tool, exporting to Acad and importing as a mass. It seems to yield quicker results than using individual triangles. It does make for too many lines though (I'm sure it's something I don't know but there it is).

I'll try and post a sample file with what I've done......and here it is, let me know what you think, I've got the topo approach (I left the topo and imported mass objects in for viewing) and the triangle roofs with slope arrow approach. I did not try the blended solid with voids (that seems like a bit of a learning curve and I'll try it when I'm not so swamped).

thanks again for the replies,

[Tom Weir]

Hi,
There is no way around saying that this is a profound weakness of Revit Structure. It is one I hav repeatedly worked with th developers to improve. I hope in the next release we will see substantial improvement in the tools. At the moment you can futz around with topo and blends and approximate things but none are too satisfying and all takes lots of time.
A chain is as strong as its weakest link, and this is the weakest link in RS.

Tom Weir
Los Angeles

[rmcelvain.103137]

Tom,

From what I am experiencing, I would have to agree with you. In my opinion the things that we need most have to do with sloped and curved framing.

We need to be able to easily identify start and end point elevations of main framing members and we also need to be able to somehow snap secondary framing to those sloped members so that when the elevations of the main framing change the secondary framing will adjust itself.

This seems like a lot of work but really, I'm spending 20 hours right now going through and sloping my beams and joists. The budget on the entire job is around 200 hours. 10% just to have the model look right when the architect imports it into their model is not acceptable. I know they're working on it and I really can't wait to see how they solve this issue.

To the development team, thanks for all the hard work and consideration of our feedback. It's a really good product with a ton of potential!