sloped roof with different height

[andy.van.slambrouck]

Hi all,

I'm currently working on a project where I have sloped steel beams as a underlay structure for my roof. So my roof with steeldeck, isolation and epdm is also sloped.

But on the left and right side of the roof I would like to give the isolation a lower height so I can lead the water to the rain pipes of that side of the roof. I attached a image of one side of the roof and in red color I drawed the profile that I like would have on that side.

Normally I could do this with 'modify sub elements'. But now I cannot use this because my roof is sloped.

I was wondering what would be the best way to achieve this roof sloped and give different height in the isolation layer?

I saw a discussion on the forum about something similar where they are talking about using in place family, but I do not see how you could give different heights with this methode.

regards

[ToanDN]

Can you use a void to cut that part out of the roof?

And, by the way, you can create a sloped roof from a flat roof by modify sub-elements.  You just need to calculate the heights of the points or edges to have proper slopes.

[andy.van.slambrouck]

I was thinking that too as a solution but then I would lose the upper layer epdm too, there wouldn't be anymore a surface on the isolation on the cutted part.

[ToanDN · Accepted solution]

You can paint the surface with the EDPM material and show the layer in your enlarged detail.

If you really want to model the EDPM, just create a Roof type with just one Layer, draw it to match the dip, and join to the main roof.

[PijPiwo · Accepted solution]

You can also use two separate roofs and modify sub elements for the insulation/EPDM roof only. Use variable thickness for the insulation layer and then join both roofs - that will cut off the excess of the insulation. The trick is, both roofs have to be apart about 1/128”, otherwise roof layers will not be visible when roofs are joined.

[chrisplyler · Accepted solution]

So this is not something I would typically model.

I would simply use the View > Graphics > Cut Profile tool in the section/detail view.

PS - it WOULD be nice if we were able to modify sub-elements on a sloped roof instead of just a flat one. I'm looking at you Autodesk.

[andy.van.slambrouck]

Thx for the advice and your example file, your model helped me to understand what you did exactly.

I saw you also placed a void extrusion. Is this because if you don't place a void extrusion the lineweight from the epdm roof is different from the main roof?

 That is what I noticed because first I only created the new epdm roof and joined both roofs, but in that case my lineweight from the epdm was for some reason thinner than the other roof and couldn't change that.

But with the void extrusion is it ok now in my case.

[andy.van.slambrouck]

Another solution, thx for your reply. But cannot make in it my case because the slope of 2% and lenght is too much, I only could make it if I would make my insulation more in height.

But it's good to know this option too.

[andy.van.slambrouck]

Thx for your advice, is possible too. I even never tried this function before

But yes,  the possibility of modify sub elements with sloped roofs would be the most effective way.

[ToanDN]

I use a void to cut the dip exactly how it is supposed to be, including the thickness of the edpm layer. It is fairly simple using a model in place void sweep and pick the edges of the roof as the path. The edpm is another roof by extrusion. The edpm and the main touch each other, but do not not overlap so that when they join, the layers of materials look correct and clean.

[PijPiwo]

Another option would be to use in-place extrusion/sweep for an EPDM. Kinda similar to what @ToanDN has proposed, but I think with the extrusion/sweep you will have more control over the shape of the EPDM and cleaner joint.

[andy.van.slambrouck]

Makes it all clear Thx again