Sloped Roof

[dhurtubise]

I've created a "flat" roof with a slope arrow for water. Now i need to fill the portion underneath to get a flat bottom.
Any suggestion. For now i used another roof with join geometry. The thing is that i have four pieces to create the whole roof, so i can't use Roof by Extrusion.
Am i left only with an in-place ?

[Steve_Stafford]

I happen to think the extra roof underneath and join geometry is a "reasonable" workaround lacking a wrote process within Revit. Another approach is to model the roof one thickness and subtract roof with either In-Place Roof family that uses a void blend or a roof host family that does the same.

Until a roof drain command deforms a roof object for us...

[luigi]

I would actually do it in reverse, since in reallife,it seems, you would be building a flat roof on a flaT structure, and then on top of this roof, placing tapered insulation. Basically I would create the flat bottom portion first, then a smaller roof (top insulation) by copying the first roof and modifying the properties (with apropriate slope and roof type)




I've created a "flat" roof with a slope arrow for water. Now i need to fill the portion underneath to get a flat bottom.
Any suggestion. For now i used another roof with join geometry. The thing is that i have four pieces to create the whole roof, so i can't use Roof by Extrusion.
Am i left only with an in-place ?

[dbaldacchino]

I'm curious...why are you trying to fill the portoin under the roof? Isn't structure typically sloped for positive drainage and then tapered insulation added to direct water to roof drains? I'm not understanding why you want to show a flat underside of roof.

[luigi]

Sometimes the A/E team decided to have dead flat roof structure, and to avoid having a flat roof, a tapered insulation added on top....it boils down to "habits"....it is definately a better design to slope the steel, so the same thickness insulation over the whole roof, and minimizing tapered insulation to get the proper drainage....I remember learning from my "mentor" that the "other" way of doing it is not a good one at all, both in design and cost....but it is still done sometimes.(that is the structure with no slope and with tapered insulation)




I'm curious...why are you trying to fill the portoin under the roof? Isn't structure typically sloped for positive drainage and then tapered insulation added to direct water to roof drains? I'm not understanding why you want to show a flat underside of roof.

[dbaldacchino]

Hehe, in our office we even warp roofs to try get water towards drains without any tapered. I think if you do a dead flat roof and add a lot of tapered insulation, that's basis for getting fired :) We use a lot of lightweight concrete decks, so if you don't slope the structure, you end up with a decent amount of tapering material over long spans, which become heavy and uneconomical.

[Mike Sealander]

I'd build a flat structure in Phoenix, but probably not in N'Awlins.

[HawkeyNut]

...Now i need to fill the portion underneath to get a flat bottom.
Any suggestion...
If you want to solve it graphically rather than in your 3D model, you could use the Edit Cut Profile tool to manipulate the bottom edge of the roof in section...

[patricks]

I recently did a roof with flat structure and tapered insulation. I actually did the entire tapered insulation portion as separate generic families, all with a single slope, and joined geometry to get all the angled lines on the roof plan where the slope changes. The "roof" element was really only the steel deck.

As for thickness, the tapered insulation started at 3/4" minimum thickness and only got up to about 7" thick at the ridges.