topic Re: How to attach floor to a sloped mass surface? in Revit Architecture Forum

How to attach floor to a sloped mass surface?

Anonymous — Fri, 10 May 2019 09:30:50 GMT

Hi everybody,

I would like to know if it's possible to attach several floor to a sloped surface mass.

The idea is to create a sloped element (mass, workplane, etc) to set and guide my floors automaticaly with the correct slope and position.

I think in this workflow to avoid the use the "modify sub-elements tool".

I searched in forums but I didn't find anything.

Thank you.

Re: How to attach floor to a sloped mass surface?

barthbradley — Fri, 10 May 2019 19:35:40 GMT

You could use a variable thickness floor and Modify Sub-Elements tools to achieve that.

Re: How to attach floor to a sloped mass surface?

ToanDN — Fri, 10 May 2019 19:29:43 GMT

Do you want the top to match the slope but the bottom remain flat where they are?

Re: How to attach floor to a sloped mass surface?

Anonymous — Sat, 11 May 2019 05:12:46 GMT

@ToanDN wrote:
Do you want the top to match the slope but the bottom remain flat where they are?

Hi.

No. I would like the different floors that I created to follow the slope. (Floor thickness constant)

Re: How to attach floor to a sloped mass surface?

barthbradley — Sat, 11 May 2019 07:52:51 GMT

@Anonymous wrote:
I would like the different floors that I created to follow the slope. (Floor thickness constant)

So basically, you want a sloped floor? You can slope a floor using the Slope Arrow tool. Or, even use the approach I mentioned before; shape edit a floor (non-variable thickness) using Modify Sub Elements.

...or you could use the Roof by Face tool to attach a roof to the underside of your Mass. No reason a Roof cant be a Floor.

Re: How to attach floor to a sloped mass surface?

Anonymous — Sat, 11 May 2019 08:50:31 GMT

@barthbradley

Yes I know I have the slope arrow and sub-elements options but imagine you have 20 floors that have to follow the same slope which is defined by a only plane. If I use the slope arrow I obtain the slope but I have to calculate the elevation (Z coordinate) for each floor.

I can do that with roofs by face option.

Isn't there any way to do the same thing for floors?

Re: How to attach floor to a sloped mass surface?

matrena — Sat, 11 May 2019 10:15:25 GMT

I don't think sloped floor creation is possible with Revit built-in tools...

The creation option "by face" works with roofs (as you said), but as floors are concerned, you can only create horizontal ones.

Unless you use Dynamo (or another programing strategy), I believe that you can only achieve that with the Slope Arrow.

You could also use the Modify Sub Elements tool as previously mentioned, but in this case you'll have to pay attention because the resulting thickness will not match the floor (type property) thickness "t"! It will be "t cosθ"

If the slope instance parameter could be assigned to a global parameter you would have a workaround, but unfortunately it’s not.

In the hypothetical situation of having a large number of this floors (with the same slope) in your project, I think creating the first one with the Slope Arrow and copying it with the "Paste to Selected Levels" tool (adjusting the boundaries afterwards, if needed) would be the fastest way to go…

Re: How to attach floor to a sloped mass surface?

Anonymous — Mon, 13 May 2019 09:28:15 GMT

Yes I think Dynamo is the easiest way because my floors will have two slope directions.

Thank you for all replies.

Re: How to attach floor to a sloped mass surface?

kgatzke — Fri, 17 Apr 2020 15:55:54 GMT

@barthbradley I can come up with a few reasons why roofs can't be floors. I don't get my metal deck corrugation in section. It can't host rebar. It's useless for structural purposes. Our view templates treat roofs and floors differently.

But according to Revit, floors can only be flat, in spite of all the wonders of mass modeling. Try creating this floor with slope arrows or by modifying sub-elements.

Re: How to attach floor to a sloped mass surface?

barthbradley — Fri, 17 Apr 2020 16:50:56 GMT

@kgatzke wrote:
@barthbradley I can come up with a few reasons why roofs can't be floors. I don't get my metal deck corrugation in section. It can't host rebar. It's useless for structural purposes. Our view templates treat roofs and floors differently.

But according to Revit, floors can only be flat, in spite of all the wonders of mass modeling. Try creating this floor with slope arrows or by modifying sub-elements.

I have no idea where you got that information, but Revit Floors CAN BE Sloped and Shape-Edited.

Re: How to attach floor to a sloped mass surface?

kgatzke — Fri, 17 Apr 2020 17:02:44 GMT

Are you using the mass to slope those floors or are you using sub-elements?

Re: How to attach floor to a sloped mass surface?

barthbradley — Fri, 17 Apr 2020 17:20:38 GMT

I'm not following. Those are Floors created via Floors by Face. The Face is a Mass Floor (shown purple in screenshot).

Top uses Slope Arrow. Bottom is Shape-Edited.

Re: How to attach floor to a sloped mass surface?

kgatzke — Fri, 17 Apr 2020 17:55:02 GMT

Mass floors are limited in that they are flat cross sections of a mass. That's not what I and I believe @Anonymous are getting at. We're looking for a way to create a floor with a compound surface from a mass.

Too often I have to deal with existing roofs where the rectangular portions between columns are level on two adjacent sides while the other two sides pitch down to a low point. This sketch illustrates what I'm talking about.

The blue rectangle is level and each joist is pitched slightly more than the last. We try not to build them like this anymore because you can't get the 1/4" positive slope without additional insulation at the level corner but we still have to deal with refurbishing existing ones.

If you try to model this surface using sub-elements - which appears to be how you are pitching the floors in your model - you don't get an accurate representation of the surface. Instead you get a deceptive napkin fold that appears to produce a drainage pitch where there actually ISN'T any!!

Mass modeling CAN produce that surface, but it seems to be only useful to create a roof but not a floor - two almost identical system families! You can substitute a roof family for a floor family BUT NOT in the ways that I consider valuable.

Re: How to attach floor to a sloped mass surface?

barthbradley — Fri, 17 Apr 2020 18:40:18 GMT

First of all, I didn't respond to the OP of this year-old thread. I was just responding to your ping today. Second, I'm not clear why you couldn't model this condition via a Roof on Mass Face - with the Mass Face having the "deformity" you are showing.