attaching beams to reference planes

[Justin Marchiel]

I am learning REVIT and trying to figure out building structure. So far i found that to create a sloping beam i need to create a reference plane then sketch the beam on that reference plane. I also found that you can't attach the top of a structural column to a reference plane, so you have to manaully add the height of the column.

My problem now lies in the fact that i can see to attach a beam (in this case joist) to 2 reference plans. What i mean is that if i had a square building, the edge of the roof would all be the same height. then to create slope i would add a column in the centre and connect it with 2 sloping beams. Then the joists wouldslope from the outer walls done to the beam. so you can imagine that each joist would have a different slope than the first due to the beam it is attaching to being sloped and the outer wall being level.

Can someone send me in the right direction please?

Justin

[janunson]

It's a big pain. Here's the two approaches i've used in the past
1. do all those reference planes.. it sucks.. but there it it.
2. Use roof-based beams. I think there's some in there by default, if not, i know theres at least one available on revitcity.com. You do the roof by drawing a blend mass, picking a face, then attach the beams to it. This way they're all sloping close-to-correctly.

Here's a thread where i was helped w/ the massing part of option 2: http://forums.augi.com/showthread.php?t=28374

[Justin Marchiel]

thanks for the reply. i was afraid that you would say that i need to create each reference plane. Very time consuming in a large steel structure building. Do you have suggestions on managing all thos reference planes? How do you name them and keep track of them?

I think that i will try option 2. being new i might have to post back.

Thanks

[janunson]

when i've done the planes, i've named them S_Roofname_# and numbered them, east to west, or north-to-south. It's definitely easier to go option 2 if you have a regular shape for your roof to follow.

[jamesd10181097]

I have a similar question. When placing a beam or entire series of beams on a referance plane, is there any way to change the angle of the referance plane and therfore all the beams. I have run into a couple of situations where the slope of the roof changed a little. Since I already had a ton of beams placed on the referance planes and I could not change the angle I ended up need to draw a new referance plane and place all the beams all over again. That was a huge pain. So in some areas I ended up leaving the previous slope. Since the slope had only changed a little it was not horrible looking but if you studied the drawing at all you could see the roof and the structure were not at the same slope.

[Justin Marchiel]

[QUOTE=janunson]

2. Use roof-based beams. I think there's some in there by default, if not, i know theres at least one available on revitcity.com. You do the roof by drawing a blend mass, picking a face, then attach the beams to it. This way they're all sloping close-to-correctly.


I tired to look at using the blend and i am not sure if it will work for my instance. I see in your example link that it works great, but i can't see how it would work for my double slope. i dont know what 2 shapes i would be trying to blend together.

anyother advice?

Justin

[Justin Marchiel]

Maybe i was too quick to respond. I still am having problems with the shape but how do i attach the structural member to the the roof that i have created by my mass extrude? also once the roof is created i can delete the mass correct? if i wanted to reshape the roof would i have to recreate a new mass, or could i just edit the current one? i guess just changing the mass will not translate to the roof too, correct?

Thanks

Justin

[James.Lupton]

The following thread has more information on this

http://forums.augi.com/showthread.php?t=29112

Personally I think there is a great need to allow a surface to become host to the components such that any changes to the surface shape will result in a corresponding change to the hosted components.

[Dimitri Harvalias]

AU Class... (Thanks David Conant :beer: )

If you are using 8.1 you can now create families that are Work Plane Based.
Create your beam as a Generic Model and go to Family Categories and Parameters. There is a new check box allowing you to make the family Work Plane Based check that box and then make sure that the always vertical box is unchecked. Re-assign the Family category to Structural framing. You need this extra step because the ref plane based option is not available in the structural framing family template :confused:
Load this family into the project file. I would suggest creating the beam with the top aligned to the ref plane in the family editor. That ensure the top (bearing face) is placed on the underside of the roof structure.
In order to simplify the placing of the beams you can create your roof (or the form which defines the roof) as a mass object. When it comes time to place your beams set your working plane to the top face of the mass by picking it. Place the beam and it should align with the plane of the roof.

I am sitting at the airport in Orlando as I type this and my battery is dying. I'll try to post a better example when I get home.

OK... the good news is I found an outlet and can continue the thought. The bad news is I missed my connection and got to stay in a flea bag motel in Las Vegas just long enough to put my feet up and go back to the airport and my travel 'day' is now 36 hours long.

To conclude, if your beams and your roof are both created or placed by picking their associated faces the beams and roof will flex with the underlying mass object. Several caveats for this type of family.
1 - they can not cut/embed into another object (since they are hosted by a plane and not an object)
2 - they can't be used on curved planes, only planar faces
3 - this is an 8.1 feature

Hope that helps