Basement below 1st Floor

[Joe_Carrick]

I have an 3 story house I'm working on.  I need to create a partial basement without effecting the elevations of the existing floors and all the structure above.  This seems to be almost impossible to accomplish.  It would be great if I could just create a room recessed into the foundation.

 

Does anyone have a good way of ensuring the floor elevations above don't change?  

[robdyck]

That doesn't sound like it should be a problem, but I'd need to take a look at the plan to know exactly why you're having this issue. If you don't want to post the file here, you could send me a PM with a link and I'll take a look.

[VHampton]

A question Joe...

 

Why won't the foundation level allow floors 1, 2, & 3 to be created without any issues?

 

Is the basement partial crawlspace and partial living? (like a split level ?) 

 

Sounds like the project might be on a hillside.

 

A quick cross section would help answer.  

 

[Joe_Carrick]

The project is definitely on a hillside.

• 1st Floor with Foundation
• 2nd Floor extends over 1st floor and grade 10' above. with foundation
• 3rd Floor directly above 1st floor area.
• all floors are at relative elevations to sea level.

I've tried just about everthing to add a interior stairway down from the 1st Floor into a room 10' below.  The results just don't cooperate and I get the 2nd & 3rd Floors floatint 20 to 40 ft above where they should be.

 

I suspect it's due to a mixup between terrain, floor, & absolute elevations.

 

Chief doesn't provide for inserting a new floor below Floor 0.

[GeneDavis]

So, Joe, you've already built a floor 0?

[glennw]

20 minutes ago, Joe_Carrick said:

Quote

all floors are at relative elevations to sea level.

 

By this, do you mean that the floor level for level 1 is not zero, but it's real world height?

 

Quote

It would be great if I could just create a room recessed into the foundation

What is stopping you from doing this?

 

Time to post a plan.

[Joe_Carrick]

38 minutes ago, GeneDavis said:

So, Joe, you've already built a floor 0?

Yes, so do I need to delete the foundation first?

[Joe_Carrick]

14 minutes ago, glennw said:

Time to post a plan.

Way to complicated with lots of custom macros.

 

14 minutes ago, glennw said:

By this, do you mean that the floor level for level 1 is not zero, but it's real world height?

No, but elevation markers report relative to sea level./ terrain.

[JiAngelo]

Joe, when you say "all floors are at relative elevations to sea level." Don't you mean all floors are relative to the terrain and you've given your terrain a relative sea level value?

 

I ask this because Chief maintains level 1 floor relative to the terrain.  We built a 3 story house 10 years back with a 2 level basement.  2x10 joists. Our desired CA levels were as follows;

0 = Cellar = ‐22' 11.5" below 1st Floor

1 = Basement = ‐10' 11.5" below 1st Floor

2 = 1st Floor = 0

3 = 2nd Floor = 10' 11-1/8" above 1st Floor

4 = 3rd Floor = 20' 10-1/4" above 1st Floor.

 

Level 2, 1st Floor, was 2' 11.5 above Terrain.

So we had to tell chief Level 1 was -8' from the Terrain.  This placed Level 2 exactly where we wanted it in relation to the terrain being 814.33 above sea level.  It also set our cellar floor to 794.67 and cellar walkout patio at 794.00 (top of footers being 794.33 everywhere else.)

 

Back then I created an excel sheet to track the elevations and overwrote our story pole values because it measures everything relative to CA level 1.  I'm fairly certain you'd create a macro variable that would handle this discrepancy automatically.

 

Long story short, if you insert a level between your plan's 0 and 1, making your first Floor now on.level 2, then tell chief your terrains relationship to new level 1 so that it is the proper height below.level 2, then all of your sea level measurements as they relate to the terrain should then be correct.  Anything referencing level 1 would be off the distance terrain is above this level.

 

I hope this helps.