Sloping an entire building

[tomm]

I need to model a building that slopes on a 1% grade over the 168'-0" length. I am able to get the floors and associated curbs to slope but the roof seems to be a problem. Does anyone have any experience with this? I did a search but came up empty handed.
Thanks
tomm

[cliff collins]

When in a roof by footprint sketch, use a slope arrow, specifying heights at the head and tail of the arrow.

This way you can control the pitch front to back or side to side.

Another way is to create a refernce plane in a section or elevation view,
and then use thr roof by extrusion tool, sketching over the sloped ref. plane.

Hope that helps.

cheers.....

[tomm]

Thanks Cliff, but I must be doing something wrong. When I try a footprint roof with the slope arrow, when I click "finish roof", I get a error dialog box that says "can't make footprint roof". Like most of these I get no explanation. I thought it was because I was trying to slope an existing roof, so I tried it with a new building. Same result. I also tried an extruded roof but can't figure out how to get it to extrude along my sloping reference plane. any suggestions?
Thanks

[cliff collins]

When in footprint roof sketch mode, using the slope arrow, draw the arrow from high point
at head, with low point at tail. Then, specify levels/offsets of heights at head and tail, then
finish roof.

Works perfectly.

The roof by extrusion method should also be very straightforward.
Try drawing a detail line in an elevation view which is at the correct angle or slope
across the building. Then use the roof by extrusion tool, go into sketch mode
and pick the detail line you drew. Then specify the start and end of the extrusion back into the building ( how far it goes in plan. )

Hope that helps--try looking at the Revit Help and Tutorials--this should be a simple procedure.

cheers

[tomm]

Thanks again Cliff, but all I get is that error dialog. It sounds very simple, but I have tried every combinaton of methods and just can't it to work. If anyone has any other ideas I am open to anything.

[cliff collins]

Can you post an example?

cheers

[tomm]

Attached is a simple building with a flat roof that slopes 15" from end to end. I can get that to work, but as soon as I edit for the 2 long sides to be at a 4/12 slope the roof cannot be completed.

[Scott D Davis]

Change the properties of the roof to "Plumb Cut" in the properties before you finish the sketch of the roof. Let me know if that takes care of it.

[dfriesen]

Thanks again Cliff, but all I get is that error dialog. It sounds very simple, but I have tried every combinaton of methods and just can't it to work. If anyone has any other ideas I am open to anything.
Do any of the roof sketch lines "define slope"? The Slope Arrow can only be used on an otherwise flat roof.

[edit] nevermind - I see my reply was way late

[tomm]

It is already set to plumb cut. If I change it to 2 cut plumb, or square, I get the same results.
Daniel: I was begining to suspect that. I need a gable roof with a 4/12 pitch that slopes at a 1% grade over it's length.

[cliff collins]

Tomm,

Please clarify:

The roof is not "flat"--it actually needs to slope in 2 directions.
15" in one direction, and 4:12 pitch in the other direction?

If so, starting with a totally flat roof, you might consider using points, and specifying heights at each point. This will give you precise control over each individual point.

-OR- Create a Mass with the geometry you need, and then convert the faces
of the mass to roofs.

cheers...

[tomm]

Thanks Cliff I will give that a try tomorrow.

[Scott D Davis]

but a 1% grade over 168' is not 15". its 1.68". Try a roof by extrusion set to a Ref Plane at the 1% grade.

[eric.piotrowicz]

My math most be way off cuz 168' x .01 =1.68' or 20.16"
In any case, would it be feasible to create the 4/12 roof as a GM family then load into the project and rotate it into the 1% grade position? I can think of a few reasons not to do it this way but if the other approaches aren't working out then it might be a clunky work around to get you what you need.

[tomm]

Thanks Cliff, using points worked fine. For the mathematicians I rounded off I am actually using 3/4% which equates to 15 1/8"

[cliff collins]

Glad it worked for you!

cheers