Basement under a basement addition?

[twalkman]

I have modeled a 1 story ranch on a very sloping lot.

Current: The ranch has a walkout basement: half slab, and half crawlspace.

Addition: An above grade family room off the basement. Because of the slope of the lot this addition will be over a crawlspace that is up to 7' high. We are considering making part of this crawlspace usable for storage.

Problem: Can I create a foundation off a foundation? Or do I need to change the current basement to the 1st floor?



p.s. I couldn't find a similar scenario using search.

[Ash]

If existing foundation on floor "0" then you need to insert new floor under current foundation (new floor 0). CA will move all your building one floor up.
In plan view, go down to floor 0.
click on "floor tool" icon (the house w/ upper floor in red)
to the right go to the "insert new floor" icon (the icon w/ two floors in white with arrow in midlle.
CA will create new foundation and move all floors one level up.
now the existing foundation will be on floor 1, CA allows no level under floor 0.

[ChiefChris]

Yes...your existing foundation should be drawn on the floor 1 level and the new foundation on the 0 level...

I've done some plans that have 3 levels of foundation based on the grade and I make the lowest level of foundation the 0 level....

[walkman]

I tried inserting a new floor off floor 0 but that's not really what I want to do as it moves the other floors above ground.

Is it possible to change floor 0 so that it's now floor 1? That way every thing stays in place and I can build a foundation level for the new basement.

Otherwise, it seems like I'll have to play around with all the floor/room structures to get them aligned properly -- which is proving to be no easy task.

[lbuttery]

Is it possible to change floor 0 so that it's now floor 1

Nope

Lew

[RMorrison]

Is it possible to change floor 0 so that it's now floor 1? That way every thing stays in place and I can build a foundation level for the new basement.

Of course. You did it the right way before; going to the bottom level and inserting a new floor. Old Floor 0 then becomes new Floor 1. You should probably then "Delete Foundation" and create a new one, just to keep the program thinking properly. (It shouldn't delete the existing foundation on Floor 1.) The other adjustment is to raise the terrain. Then you should be good.

[ChiefChris]

Richard - I don't believe that you can insert a floor below floor 0. If you go to floor 0 and instert a new floor, CA will put in a new level between 0 and 1...thus making a new blank floor 1 while keeping your first floor 0 at the same level....

[Tim O'Donnell]

Nope

Lew

Richard - I don't believe that you can insert a floor below floor 0. If you go to floor 0 and instert a new floor, CA will put in a new level between 0 and 1...thus making a new blank floor 1 while keeping your first floor 0 at the same level....

not so...Richard is correct...in v10, if you are on level 0 it will insert a new blank level 0 and move everything else up one level..

Walkman...you can adjust the terrain independant of the building by opening the terrain dbx>general tab>building pad section... and uncheck the box for autocalculate elevation ...then enter a new value adding to the existing moves you building up...deducting from the value moves your building down...so say it is 18" and the floor level is moved up 7' ...deduct 84" from the 18" and enter -66"(18"-84"= -66") to move it back to the location it was in relation to the original floors

[lbuttery]

Tim:

I was responding to his post #4, where he had aleady tried inserting a floor and didn't like the result.

He wanted to know if he could relabel floor 0 and my response was nope.

Lew

[Tim O'Donnell]

Is it possible to change floor 0 so that it's now floor 1

Nope

Lew

this is what he asked and what you responded to...

the correct answer is yes...go to level 0 and insert a floor...the original floor 0 becomes floor 1 and a new blank level 0 is inserted...and once he does that he can/will need to move his terrain as needed to accommodate the new floor level...which is very easy to do in the terrain dialog

[lbuttery]

Yes, but he had already tried inserting a floor and didn't like the result.

Hence, my reply. I may have read his 2nd question wrong ?

Anyway, I know how to insert floors and use edit area etc. and he knows now also

Lew

[walkman]

Thanks for the responses and help. To clarify, CA added a new floor 0 below floor 1. For some reason it caused my main level to rise 32" pushing everything above grade and made several other changes relative to floor structures, etc.

To fix things I,

- deleted the existing foundation
- corrected the "structures" and "specifications" for the floor and room dbx for the new floors and attic & then recreated the walls and roof
- this put everything back in the right place

- created the exterior walls for the addition on the new floor 1
- created a new "blank" foundation
- turned on "reference display" so I could see the walls above
- created foundation walls for the addition on the new floor 0

[ChiefChris]

not so...Richard is correct...in v10, if you are on level 0 it will insert a new blank level 0 and move everything else up one level..

My bad....

The process moves the entire model up so that the new floor 0 is the foundation...but your exitsing foundation (which was floor 0 now floor 1)..is moved up and what is now floor 2 (ex. floor 1) is no longer at level 0".....which can be changed of course.

[Curtis Johnson]

TW??

Is what you want to do is to just add a storage room behind your "interior" foundation wall? If that is all you are doing, then all you should have to do is add more foundation wall where the room will be located. If I have guessed right, then I would suggest keeping the storage room slab at the same elevation as the basement, otherwise you may need to make a custom door to access your storage room. If the storage room is inboard from the side foundation walls, then the excavation for your basement gets a little more interesting depending on the distance from the storage room foundation walls to the uphill and side walls. If the storage room side walls are in line with the main structure's side walls, then it isn't much of a problem other than putting in foundation steps where you need them and making sure all your footings are on "solid ground" (undisturbed soil or properly compacted approved fill). If I am all confused, it won't be the first time. If you can post a picture or two of what you are trying to do, that would be helpful. If you need help posting pictures, Louis & Katy's website has a tutorial that covers this; it might be covered in CA's help database articles too.