Roof Pitching Point Question

[iankids]

Hi All,

I am a little confused (not an uncommon occurrence as my wife would say), as to the best way of getting a roof to pitch from the correct element of the wall structure.

For a brick veneer wall, the roof pitching point, (the point at which the rafter / truss connects to the wall) is the outside edge of the timber stud frame. From this point, the roof pitches down beyond the external brick cladding to the eaves at whatever distance.

As far as I can see, no matter which way I input the info, when creating a roof by footprint it will always pitch from the outside edge of the brick cladding. In doing so, for a roof at a 30 degree pitch it is sitting 81mm ( 3.18 inches) higher than it will in real life.

Whilst often this is not a problem, sometimes when one is trying to squeeze in a window directly under the eave it becomes critical.

Apart from figuring out what the difference is & adjusting the roof manually (very unrevit imho), is there any other way which I have missed?

Thanks in advance

Ian

[Chad Smith]

I believe the only two options you have are to manually move the roof down, preferably doing a reference move in section for accuracy, or drawn two walls for your veneer wall, which is something I wouldn't be doing.
It would be nice to have a roof parameter to pitch from the core of the wall for housing situations.

[iankids]

Thanks Chad,

The moving it down in a section view is what I had been doing, but had kinda thought I must have missed something!?

This seems to me to be a very inelegant part of Revit. Maybe something for the Wish List - if it hasn't already been listed previously.

Thanks again,

Ian

[patricks]

Yes, Revit will do what you are after, automatically. I'm surprised so many people don't know about this. Maybe it's not in the Help file and I just figured it out on my own or something.

If you draw the roof footprint by picking walls, checking Extend To Core, and specifying your overhang distance (from outside face of core), and then change the roof from Truss to Rafter, it will then sit on the inside face of the stud just as it should.

See my post in this thread:
http://forums.augi.com/showthread.php?t=73221

[iankids]

Thanks Patrick,

That certainly fixes up the rafter construction which is pitched from the inside edge of the stud wall.

It still seems to me to be incorrect for a truss roof where the outside edge of the bottom chord is flush with the outside edge of the top of the top plate, with the bottom edge of the top chord meeting at this same point.

Am I still missing something?

Your help is greatly appeciated

Cheers,

Ian