Sloped Concrete Porch Slab

[Ed_Orum]

This house has a 10' wide, 4" thick concrete slab for the porch floor.  The outside edgeof the slab will be thickened to 12" Deep x 6" Wide.
The slab needs to have a slope of 1/4" per foot, so over the 10' distance the outer edge of the slab needs to be 2-1/2" lower than the edge against the building.

So, my question is how does Chief apply a slope to a slab?

Thanks in advance.

Lane

[rlackore]

Chief doesn't have a function to slope a slab, so you'll need to roll your own. Possible solutions are: polyline solid; or a ramp applied to the top of a flat slab (or floor). I'm sure there are other methods.

[CharlesVolz]

59 minutes ago, rlackore said:

Possible solutions are: polyline solid; or a ramp applied to the top of a flat slab (or floor).

And/or just a ramp by itself, a roof or ceiling plane and my favorite . . . an arrow with a note.

[robdyck]

I'm with Charles, most of the time a note will suffice. When I must show a slope, there are different approaches based on your desired end result. For a ground level sloped slab that may be irregular in shape, I'll use a 3d solid. For a rectangular sloped slab that will have railing on an edge, I'll use a ramp with my own railing wall set to 'follow stairs'. For a sloped balcony that needs to be framed, I'll use a roof plane and possibly a ramp as well (to get the railing to slope). The project has to be pretty special for all this!

[GeneDavis]

If you just absolutely must have it for 3D realism and the customer is paying for it, draw the 4" slab and put a 3D solid wedge atop, 2.5" to zero.

[Ed_Orum]

Thanks everyone.
I was hoping X15 would be able to do this.  I am still working with 13 because I don't see enough "substance" to justify upgrading.  Lots of nice fluff in X15, but not enough on the meat and potates end of the program.
If the programmers at Chief are listening, wouldn't this be a great addition to an Architctural CAD program?  There is not a garage floor in any residential building that does not have a slope (by code) so couldn't you add a feature where you set the elevation of the slab on one end, and the elevation of the slab on the other end, click the Apply button and ta da, the magic of a program that reflects real world conditions.
Work arounds are great, but this really seems like a very basic function, as basic as a flat slab itself.
Just my humble opinion.
 

[Gawdzira]

The real time ray tracing/ rendering changes from 13 -15 are huge. But, it will mean that you may need a new computer or graphics card. 

[GeneDavis]

Garage floor slopes are typically more complex, with hips and valleys.  I just draw the lines and annotate.  No one has ever asked for 3D realism in something so subtle.

[rlackore]

5 minutes ago, GeneDavis said:

No one has ever asked for 3D realism in something so subtle.

 

It's not just 3D though. When you cut a section, you have to use CAD to properly illustrate the slope. Lots of things can be affected by the slope: porch columns, piers, top-of-foundation, minimum thickness of a wear layer (at precast decks), etc.

[GeneDavis]

58 minutes ago, rlackore said:

 

It's not just 3D though. When you cut a section, you have to use CAD to properly illustrate the slope. Lots of things can be affected by the slope: porch columns, piers, top-of-foundation, minimum thickness of a wear layer (at precast decks), etc.

And if this is your absolute need, gotta have it, write it up in the Suggestions section.  For me, the sloped sections would be drawn like the way we draw roof planes.  The image shown here is of a 22 x 22 2-car garage, sloped the way one of my builder clients does it.  His flatwork sub places screeds to get it right.

[Ed_Orum]

2D is not a problem, but showing it in 3D is. So I put a disclaimer on all of my 3dViews that they are an "artist rendering" and may not fully represent the actual structure.  Too bad, but thats the lay of the land.

[CharlesVolz]

On 10/17/2023 at 3:24 PM, rlackore said:

Chief doesn't have a function to slope a slab, so you'll need to roll your own. Possible solutions are: polyline solid; or a ramp applied to the top of a flat slab (or floor). I'm sure there are other methods.

 

It would be nice if CA would improve/expand the ramp feature or combine its features with slabs so that we could:

1) shape/angle all four the sides

2) create complex curves (or join ramps to create them)

3) have material layers (like roofs & floors)

4) be used as a terrain feature

5) include arrows showing downward slope and amount of slope (by length) with number and size controlled in DBX (like revision clouds are)

 

I do not know if I would use it for subtle slopes like garage floors but it would be great for getting the terrain looking better adjacent to buildings, especial at porches, entries, garage overhead doors, etc.

 

Any additional ideas before I send this in as a request?

 

 

[robdyck]

39 minutes ago, CharlesVolz said:

Any additional ideas before I send this in as a request?

In response to some of the earlier conversation in this topic; While in some ways a sloped garage floor modeled accurately may seem trivial, when designing an accessible home with an attached garage and a zero-threshold concept, the accurate modelling of the garage floor and exterior sidewalk slopes are critical. These calculations shouldn't be left for trades to make on site.

I appreciate that you'd take the time to submit a comprehensive suggestion, Charles!

Railing control on a per edge basis (like landings) would also be helpful to add to your suggestion.

[CharlesVolz]

10 minutes ago, robdyck said:

In response to some of the earlier conversation in this topic; While in some ways a sloped garage floor modeled accurately may seem trivial, when designing an accessible home with an attached garage and a zero-threshold concept, the accurate modelling of the garage floor and exterior sidewalk slopes are critical. These calculations shouldn't be left for trades to make on site.

I appreciate that you'd take the time to submit a comprehensive suggestion, Charles!

Railing control on a per edge basis (like landings) would also be helpful to add to your suggestion.

Got it!

[Kbird1]

On 10/19/2023 at 11:01 AM, Gawdzira said:

The real time ray tracing/ rendering changes from 13 -15 are huge. But, it will mean that you may need a new computer or graphics card. 

 

Not in Ed's case the A2000 is an RTX capable Workstation GPU...........   https://www.nvidia.com/en-eu/design-visualization/rtx-a2000/ 

 

The down side is the need to go subscription these days.....

 

 

* On topic       Yes I agree,  we should have had Sloped Slabs by now being they are a Code requirement everywhere for 10yrs? .....

 

M.

 

[RobDesLLC]

On 10/17/2023 at 4:01 PM, Ed_Orum said:

This house has a 10' wide, 4" thick concrete slab for the porch floor.  The outside edgeof the slab will be thickened to 12" Deep x 6" Wide.
The slab needs to have a slope of 1/4" per foot, so over the 10' distance the outer edge of the slab needs to be 2-1/2" lower than the edge against the building.

So, my question is how does Chief apply a slope to a slab?

Thanks in advance.

Lane

 

I set the floor elevation to the lowest point and let it stay flat. I address the slope in notes and annotations. In my opinion, most of the time the juice isn't worth the squeeze for sloping slabs.

[Ed_Orum]

On 10/26/2023 at 11:37 AM, RobDesLLC said:

 

I set the floor elevation to the lowest point and let it stay flat. I address the slope in notes and annotations. In my opinion, most of the time the juice isn't worth the squeeze for sloping slabs.

The problem is a couple of local building inspectors who want the plans to show the slope in section views.  I did a section view, then had to change it to a cad view, then had to slope the garage floor in cad.  Not so bad except if something changes, and the section in cad must be re-drawn.
The other issue is with the garage door heights.  Since the floor is 2" lower at the door, the automatic story pole dimensions are inaccurate.  Again, back to CAD or over riding the dimension.

[Chrisb222]

45 minutes ago, Ed_Orum said:

I did a section view, then had to change it to a cad view, then had to slope the garage floor in cad.  Not so bad except if something changes, and the section in cad must be re-drawn.

 

I would just indicate the slope using cad in the live section view. Then if something changes, the model will update live, and you'd just need to adjust the cad for the slope. 

[RobDesLLC]

On 10/30/2023 at 12:20 PM, Ed_Orum said:

The problem is a couple of local building inspectors who want the plans to show the slope in section views.  I did a section view, then had to change it to a cad view, then had to slope the garage floor in cad.  Not so bad except if something changes, and the section in cad must be re-drawn.
The other issue is with the garage door heights.  Since the floor is 2" lower at the door, the automatic story pole dimensions are inaccurate.  Again, back to CAD or over riding the dimension.

 

That is insane. In my opinion, you should talk to the building official about it. If your plans went through the plan reviewer and a permit was issued, it isn't the inspector's role to make that demand. They have the authority to demand a revision for a code compliance issue, but not a minor graphic issue such as this. They're way out of line. 

 

A design alternative I use regularly that could solve the problem in a less confrontational way would be to specify a flat garage slab with a 1.5" x 11.25" recess at the overhead door opening. The recess would have a chamfered edge. I then use a standard recess detail for this section of the slab, show a dashed polyline on the foundation plan and call out the recess detail, and make no corresponding change to the model itself.