Roof Face Alignment

[Batman]

I am building a Revit model for an existing building to which I am trying to add an extension with roof.

I am having trouble trying to add the new roof to the existing roof as I have found that (due to the existing wall and roof positions) that new face will end up slightly higher than the existing and thus it won't work when I try to join them. I can alter my wall height for the new roof to accommodate the roof alignment but need to know how this could be done in Revit.

Can you align roof faces in Revit or some other way to make sure that the surfaces are even?

What is the best way to add the roof in Revit that allows me to make sure that it is aligned with a face of an existing roof?

[Roger Evans]

In a real life situation I wouldn't align them but would set the new roof back & below the hip
This allows for better detailing & distinction between old & new
ie more or less as it seems you have drawn it

[beegee]

Can you align roof faces in Revit or some other way to make sure that the surfaces are even?

What is the best way to add the roof in Revit that allows me to make sure that it is aligned with a face of an existing roof?
Yes, you can align roof faces.

Cut a section through the existing main roof that will show the new roof in its view extents.

In that section use the align tool to align the new roof with the existing roof.

Now use the Join Roofs Tool.

Now cut out a portion of the existing roof, if necessary, where the new roof joins in, using the Opening Tool.

Post back if you need clarification / more detail on any of those steps.

[Batman]

Yes, you can align roof faces.

Cut a section through the existing main roof that will show the new roof in its view extents.

In that section use the align tool to align the new roof with the existing roof.

Now use the Join Roofs Tool.

Now cut out a portion of the existing roof, if necessary, where the new roof joins in, using the Opening Tool.

Post back if you need clarification / more detail on any of those steps.
That align tool is fantastic. Thanks Beegee.

One slight problem, the join tool reports that part of the roof will miss the target face and as such won't join. Its a small bit at the peak of the new that strikes slightly above the existing ridge by a small amount.

Is there a way to blend it so it will accept the join?

[Batman]

Actually I have found that when you use the align tool for the roof, as I did in the section, the roof doesn't align exactly.

As you zoom closer you can still see a mis-alignment, I thought that I needed to use the tool again, instead it just brings the rooves closer together but it doesn't actually align them properly, as I noticed when I zoomed in further and still found a gap.... you could go on forever but there is point that the align tool won't work on such a close view.

Is this align issue a bug?

Also, after fidling with the roof I managed to get it to join, but the ridge doesn't do as I hoped. Is there a way to fix this (refer attached pic)?

[Scott D Davis]

Drop the ridge of the roof down that is slightly too high and getting cut off? You should be able to slect the roof, then grab a grip on the ridge, and pull it down.

[Batman]

But what if the ridge needs to stay where it is?

[Scott D Davis]

How would you build it? The one roof would be slightly higher, and the little "peak" would get tapered to the slope of the adjacent roof? How much is it off? An inch or so?

[beegee]

Vince, as with most things in Revit, there are a number of ways this can be done.

Here's one I've used before.

1. Join the roofs, accepting the strange result. See image 1. ( similar to your image above )
2. Model an infill roof . I usually y do that using a roof by extrusion and selecting a reference plane at say the existing ridge. See image 2.
3. Join the infill roof to the main roof using Join Geometry. See Image 3.

HTH.

[Batman]

I appreciate your view Scott, but my point is whether it can be done in Revit. Given a higher 'peak' it seems it would do the same thing anyway (chop the ridge for the extended/joined roof).

If I can model it in ADT I should be able to model it in Revit....right?

[Batman]

Vince, as with most things in Revit, there are a number of ways this can be done.

Here's one I've used before.

1. Join the roofs, accepting the strange result. See image 1. ( similar to your image above )
2. Model an infill roof . I usually y do that using a roof by extrusion and selecting a reference plane at say the existing ridge. See image 2.
3. Join the infill roof to the main roof using Join Geometry. See Image 3.

HTH.
Thanks for the work around. I'm getting the feeling rooves are not 1 of Revits strong features.

What if I can build the roof as 1 piece ie. as 1 phase with different pitching heights. Could the attached (done in ADT) be done in Revit?

[Scott D Davis]

If I can model it in ADT I should be able to model it in Revit....right?
You can model it any way that you'd like, but if that's not the right way to built it.....

If it were more like beegee's example where there was a more substantial 'gable' on the higher roof, then I could see why you needed to model it like that. You example had such a slight difference, that you wouldn't really build it that way. You would either set the ridges at the same height, or offset them more significantly to express an architectural detail.

Just because you can model it in ADT, doesn't mean that its buildable.

[beegee]

Thanks for the work around. I'm getting the feeling rooves are not 1 of Revits strong features.

I can't see the difficulty with my method , to achieve what you want.
It takes hardly any time at all to do.

[Batman]

Scott, I disagree, it may be that if you can model doesn't mean it is easy to build. Regardless, the software should be able to model it because in principle it is a plausible method to construct the roof, whether it looks silly or not. The fact that beegee's roof is bigger and looks more 'reasonable' still hasn't fixed the problem has it.

Don't try and make me look biased towards one CAD or the other. If people are going to be defensive about Revit rather than admit full frontal (to answer the questions directly) that something doesn't work whats the point of this forum. I'm sticking to facts, if Revit can't do a roof as ADT can then what do you expect, change the design to make it simpler for the tools at hand and tell the client 'I can't do it'.

Beegee, your solution is a work around and if it could be done better then thats how it I'd rather do it is all. I'm only asking what if.

I post here hoping to receive methods to solve my problems. I appreciate all assistance received through this forum and hope one day to be able to be able to pay it forward within the same forum.

[beegee]

Beegee, your solution is a work around and if it could be done better then thats how it I'd rather do it is all. I'm only asking what if.

OK, heres an even simplier solution.

Draw the new roof sketch so that the gable end aligns with the existing roof ridge line.
Finish sketch and join geometry.

[Scott D Davis]

Don't try and make me look biased towards one CAD or the other. If people are going to be defensive about Revit rather than admit full frontal (to answer the questions directly) that something doesn't work whats the point of this forum. I'm sticking to facts, if Revit can't do a roof as ADT can then what do you expect, change the design to make it simpler for the tools at hand and tell the client 'I can't do it'.
That's not it at all. Beegee showed one way it could be done. I'll try to come up with more for you tomorrow. I wasn't being defensive, and there was certainly no reason to admit "it can't be done" because it can. Finally, it's not about making it more simple so it can be modeled in software, its a question of modeling it so it can be built simply. Don't tell the client it can't be done, tell the client, "sure, we can do anything, but it's gonna cost you more $$$." Is that ridgeline on a roof peak that you probably wont see from the ground worth the extra cost to make 3 inches higher?