Changing Floor Joist Size--Is this the mortal sin of Chief?

[Ed_Orum]

This building is a "slab on grade", or at least that is what we call it here in the North East.
The first floor is a slab, the slab sits on top of the stem walls.  

The stem walls have a footing.

So far, so good.

The ceiling height of the first floor is 120"

I drew the plan with the 2nd floor joists at 9-1/4" with a 3/4" Plywood Sub Floor.
So, from top of the slab to the top of the first floor wall plate is 120", and from top of the slab to the top of the 2nd Floor Sub Floor is 130".

The second floor ceiling height is 108".

So, from the top of the slab to the top of the second floor wall plate is 238" (19'-10")

So far, so good.
But I need to change the 2nd floor floor joists to be 11-7/8" with a 3/4" Plywood Sub-Floor.
So, thinking it would be simple I went in and changed the ceiling joists on the 1st floor to 11"-7/8 with a 3/4" Plywood Sub-Floor.

And that was the beginning of another version of "Chief Frustration" or "Why I Should Have Stuck With Vaudeville".

The 2nd floor ceiling height will not stay at 9' with the new floor joist height, nor will the first floor ceiling height.
No matter what I try, something always reverts back to the original 1st Fl. ceiling joist/2nd Fl Floor Joist size of 9-1/4".

So what is the proper procedure for changing a 2nd floor, floor joist AKA 1st floor ceiling joist to a different size?  
There must be a sequence that has to be followed.
I cannot attach the plan because it exeeds the maximum allowable size.

Thanks in advance,

 

Lane

[tundra_dweller]

A couple things you can try:

Go into your default settings->Floors and Rooms->Floor Levels->2nd Floor and change the structure to your new joist size here first. Also make sure the ceiling heights for you 1st & 2nd floor are set correctly in this dialogue.

 

 

 

If you resize your floor joists through the room spec dialogue, try checking "Lock Floor Bottom" in the "On Structure Resize" option.

 

In either case if you don't have auto roofs on, you might have to manually raise your roof planes the height difference of the new floor joists.

I've been through this tail chasing scenario many times, it can be a total PITA.

[Ed_Orum]

Thanks, I was afraid it was very simple and straightforward, and I was about to lose all faith in Chief if it was as simple as changing a joist size and then everything above it re-sized and re-positioned automatically.
But, Chief does do a great job of renderings, so even if it takes hours to get the model right it has that going for it.  Sadly accuracy in the model should take priority over a rendering, but that does not seem to be a big strength in Chief.

I am sitting here with a friend of mine who asked me to walk him through doing drawings in Chief.  If he laughs any harder they will probably hear him in Coeur D'Alene.  He draws in a competetiors program and told me to come over to his office and he can show me how to do it in about 4 clicks.
So I will end up doing what I have learned how to do very well in Chief--fake the elevation views, override the story pole dimensions, and change the section views to CAD views so I can make the adjustments.

[Kbird1]

6 hours ago, Ed_Orum said:

I went in and changed the ceiling joists on the 1st floor to 11"-7/8 with a 3/4" Plywood Sub-Floor.

 

That is your Mistake, with a 2nd Floor above there is no Ceiling Joists on the 1st floor, they are all Floor Joists..... of the 2nd Floor Structure.

 

Chief would only use the ceiling joists Setting in Areas that are not covered by the 2nd floor ie a 1st floor bump-out for example.

 

M.

[Ed_Orum]

I finally got it.

Step 1, raise the roof.

Step 2, change 2nd floor joist sizes.

Step 3, change 2nd floor ceiling height.

Step 4, change 1st floor ceiling height

Step 5, change all window and door height above floor relative to new floor heights.

Thanks!

 

[SNestor]

@Ed_Orum - all you needed to do in the beginning was open “defaults” >Floors and Rooms>2nd floor. Change the joist size…

 

As long as each room is set to use defaults the model will update. You may have to rebuild the floor framing…but that’s it. 
 

If you have already built the roof and had turned off auto rebuild roofs you will have to manually move the roof up/down depending on the difference in the joist size. 

[GeneDavis]

Floor structure is a room setting not a joist setting.  You don't edit the joists for height.  You edit the floor structure of the room.  With autoframing on, Chief will change the joists from whatever to your new whatever height.  What was it, 9.5 but needing 11.875.

[Ed_Orum]

Thanks,
I took the following steps :
Raised Ceiling Height.

Changed 2nd floor Height

Changed 1st Floor Height.
I thought Chief would automatically raise everything if I raised the 1st floor ceiling height, but each one had to be done manually. Then it worked.