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Joef
2006-02-16, 12:47 AM
I know there is a trick to creating a roof with eaves at different heights (but the ridge still in the middle of the supporting walls) but I cannot recall it. Any tipsters out there that can clue me in?
Thanks,

Joe

sfaust
2006-02-16, 12:55 AM
I just shut down revit for the day, but I believe if you go into the properties of the sketch line defining the eave there is a property for "offset" or something like that which will let you move the eave up and down.

I also think that if you use pick walls and an overhang the ridge will be between the walls anyway, but I'm not sure.

Hope that helps.

Tobie
2006-02-16, 03:03 AM
When you create the roof, use "roof by footprint". When you have the different overhangs the starting point on the wall would be the same but the eaves height will change.

bowlingbrad
2006-02-16, 01:49 PM
During the sketch mode of roof by footprint, select an eave line, open the properties of that line and give it an "offset from roof base" value.

Max Lloyd
2006-02-16, 02:11 PM
Either I have, or everyone else has misunderstood the question.

You want differing eaves heights, not overhangs. But you want the ridge line to stay in the middle relative to the 2 supporting walls. Therefore, the suggestion about using the wall plate offset on its own will not suffice as you also need to adjust the angle of the roof. (the 2 pitches clearly can not be the same in order for the ridge to remain in the middle.)

The easiest way to do this is draw a footprint roof, with whatever overhangs you want. Draw a ref plane centralised between your 2 supporting walls. then use the slope arrow function to draw a line from say the inside of one supporting wall to the ridge, then repeat for the other side. If you now go to the properties of those arrows, you can set the starting height and end height. This should get you what you want.

Do note though: as revit does its roof calculations to the underside of the roof, it is the inside intersection that is perfectly centred between the 2 walls and not the external intersection (ridge). You can adjust this of course, but as there are 2 differing slopes (assuming the roof thickness is the same for both slopes) it is of course impossible for both junctions to be centred.

The other option, which may be even easier, is to draw it as 2 roofs, using a common ridge line, and just adjust them from an elevation view until the ridge lines up!

Hope this helps.

Max.

(sorry for the double post!)

bowlingbrad
2006-02-16, 02:23 PM
Sorry, didn't read the complete post.

Another way is to create two roofs. The first with equal ridges on each side of ridge. Then a second with a single slope. Move the second to align with the first and join geometry. Adjust the location of the lower eave in sketch mode.

Max Lloyd
2006-02-16, 03:04 PM
Brad, this does not keep the ridge in the middle relative to the 2 eaves. You need to have 2 different angles for this to work.

Joef
2006-02-16, 03:37 PM
Thanks for all the suggestions! I will try them out today. I think the trick is to use "pick walls" when setting out the roof. That keeps the ridge in the center when you adjust the eaves and the overhang.

Joe

rookwood
2006-02-16, 03:53 PM
To keep the ridge line CENTERED ON THE STRUCTURE and have 2 eaves at different heights with identical overhangs, you would HAVE to have 2 different roof slopes. Just simple geometry.

The roof with the lower eave height would require a roof slope (pitch) greater that the roof with the higher eave height.

Of course this applies only to GABLE roofs and would not, or could not, work for hipped roofs. I suppose you could force some type of funky return, but it would be funky.

wwyatt.87825
2006-03-26, 05:03 PM
I am new to Revit and currently trying to transfer an Autocad project into Revit, which consists of some larger roof overhangs that have varying slopes within the same overall roof footprint (think of a piece of paper that has been cut partially in half and then you fold one side up and the other side down, with both 'cut' sides at different slopes than the 'non-cut' side, i.e. you have three slopes coming together along one valley line)
I tried making three separate roofs and joining them, but that hasn't been working, and I tried making one large roof and then using the slope arrow function to chnage the slope properties, but I can't control where the 'shared' valley line is located.
Is there anyone who can help me out?

Steve_Stafford
2006-03-26, 05:56 PM
I know there is a trick to creating a roof with eaves at different heights (but the ridge still in the middle of the supporting walls) but I cannot recall it. Any tipsters out there that can clue me in?
Thanks,

JoeSlope arrows

Joef
2006-03-26, 07:38 PM
Thanks Steve!

I finished this project a few weeks ago but can't recall now which method I used! :smile: Thanks for all the tips.

Joe

Tobie
2006-03-26, 10:02 PM
Please send image wwyatt