Starting A Project With The Foundation On Level 1...good Or Bad Idea?

[j_in_ky]

So here's the deal...I've got a project where the client has an existing garage and what's to add a second story to it and add a wing to it. But here is the tricky part...the garage is sunken into the terrain because the alley that the garage uses is lower than the rest of the terrain. So just behind the garage, the terrain is a foot or so below the gutter line but then dramatically slopes down to the level of the alley (the slab of the garage roughly). To the side of the garage is a set of stairs to get from the garage up to the backyard and to the right of the stairs is more terrain, with a slab on it, which is the same level as the backyard. I attached two photos so you can see.

 

We are only drawing the garage and the terrain and not the main house because we're not doing anything there. So essentially the existing garage will still be a garage but will also be the foundation/basement for what is going on top. We are just starting the design so don't have a floor depth yet so the question is should the existing garage go on the foundation level or the floor one?

 

I'm worried that if we draw the existing garage on the foundation level, which would make sense because it essentially will be the basement of what is to come, we will run into problems once we build the first floor because as we adjust where exactly 0' 0", from trying different floor systems, trusses, I-joists, joists that have different heights, it will start moving the floor of the existing garage. Which can't move because it's already there!

 

I don't want to have this project just about wrapped up and after talking to the contractor we decide to change the floor system and what should be a simple change becomes a nightmare because I have to go and fix what ever havoc occurs after changing the floor 1 height.

 

So I'm thinking that I'll just draw the garage/foundation on the first floor and go from there but I just have never done that before and am wondering if anyone has come across a situation like this? I mean would I put the terrain on level 2 than? I just haven't come across a situation quite like this before.

 

Any insight would be appreciated. Thanks

[Kiwideziner]

FOUNDATION LAYER 0  for the foundations is my way of thinking

[CJSpud]

I do the same as Graeme .... foundations at level or floor = 0.  BUT, there are many Chiefers who prefer to have there foundation level at floor 1 because of code/building department issues, etc.  You'll have to decide what works best for you.

[Bill_Emery]

Most of the projects that I do have a crawl space, a spread footing, and a stem wall. foundation on level 0 works well.

If I have a basement, or a daylight basement, I prefer to use floor 1 for the basement, or daylight basement, and use level 0 for the foundation/footings for the following reasons.

Although information can be sorted by layer, and annotation sets, I find it much easier to sort the footing and floor information by having level 1 for the floor information, and level 0 for the foundation/footing information. This method just keeps it simple. We're dealing with two distinct sets of information, and separate levels makes sense.

The answer may come down to what seismic zone your project is in; if you're in Zone D1, or D2, or your project is in California; then keeping the basement, and the footings separate levels is the best answer. keeping them separate also makes sense with engineered retaining walls and for foundations with complex insulation details.

[j_in_ky]

Thanks for the responses.

 

I am with you all in that I always put the foundation on 0 because usually I am drawing something that already has a first floor. I do mostly home additions so I don't start by drawing the foundation, I rough in the first floor before I go to other floors and to the foundation to get the existing.

 

It's just in this case, which I haven't come across before that I can remember, the existing is just a garage that is going to end up being the basement/foundation level for all intents and purposes and the height, relative to the slab of the garage, of the next story is undetermined. It's height will be determined by whatever structure we decide is right for the project and other design considerations which may pop up.

 

My worry is by making the existing garage on the 0 level, the height of the first floor, which in Chief is 0 is determined by the ceiling height of the garage. Once I have the garage drawn and modeled I need it to not move because I'll have the terrain modeled and everything will be ready to go. When I start the first floor and I realize that actually (hypothetically) I may want a small entry with two or three steps to get into the first floor, I think that means I'll have to move all of the existing that I already have accordingly. Now I can do that with edit area, etc. but it will be a huge pain if, which often happens, if I try a few different designs and I'm having to constantly make sure and adjust the existing back to how it really is. 

 

My thought is by putting the existing garage on the first floor, it's slab becomes zero and I can change whatever I want above it without it affecting what is in situ. I just have never done it before. This particular situation just doesn't come up often. So my worry isn't about codes it's about the nuances of the software. If that makes sense.

[WendyatArtform]

Life will be a lot easier if you use Chief the way it was designed to be used.  Put the first floor on the first floor (Level 1).  If your garage is at grade, put it on the first floor.  If you manually assign a floor height after you create it, it will not change that.

 

You can use some QC tools to keep an eye on things like this that are "mission critical".  We have a "working" layerset where we do most of our editing.  In that layerset is a "working" layer that holds some QC tools.  For splits and other times when we want to keep a sharp eye on floor height - one of those is a floor height backcheck - desired height in just text, actual via a text macro.

 

 

 

[HumbleChief]

My thought is by putting the existing garage on the first floor, it's slab becomes zero and I can change whatever I want above it without it affecting what is in situ. 

That's a good strategy and another option is to put the garage on floor 1 and set its floor height to a negative number below the main living floor (floor level 2) above which can be set at '0' - 0"'. Both strategies work bit since most of the of design work will probably be done on the floor above it might be nice to have that floor set to '0' - 0"'.

 

Also if you consistently set the main living floor at '0' - 0"' you have a conscious place that all your buildings, now and in the future, will start and stop their floor levels from.

[HumbleChief]

Here's a vid of the above strategy. There are a few land mines that you must avoid and if you watch through to the end you will see THE SINGLE MOST FRUSTRATING THING ABOUT CHIEF'S STRUCTURE DBX.  Hope this helps.

 

http://www.screencast.com/t/Qsc4usSSnwDP

[HumbleChief]

Here's a quick terrain video that may or may not be relevant.

 

http://www.screencast.com/t/geVV2Cbm

[jbaehmer]

I have done a number of basements and don't run into a lot of these issues.  They come up once in a long while, but not as much as I hear about from others.  Not sure what I am doing different besides that I don't put a basement on floor one.  I always have the basement on floor 0 and it works smoothly 98% of the time.  I have watched the videos by others, but just I can't seem to understand why the basement would be put on floor 1.  Is there anyone who does put basements and such on floor 1 that wants to meet up online too discuss this with me sometime this week?  Maybe there is something we can learn from each other.  Shoot me an email if interested....I really would like to understand the concept and as to why.

[WendyatArtform]

That's a good strategy and another option is to put the garage on floor 1 and set its floor height to a negative number below the main living floor (floor level 2) above which can be set at '0' - 0"'. Both strategies work bit since most of the of design work will probably be done on the floor above it might be nice to have that floor set to '0' - 0"'.

 

Also if you consistently set the main living floor at '0' - 0"' you have a conscious place that all your buildings, now and in the future, will start and stop their floor levels from.

 

What he said.

 

At the expense of repeating myself - you will almost always be better off using Chief the way it was designed to be used.  

 

To understand how Chief is designed to work, do this quick exercise:

Start a new plan using the default template (profile.plan).  Draw a simple first floor with an attached garage.  Assign the garage to be the room type "garage" and then let Chief build a foundation using the Floor Tools.  If you now look at the garage room dbx you'll see that Chief has automatically dropped the garage slab.  That's the way it's designed to work.  You can change the amount it's dropped it, and it will hold that setting.

 

And another important thing to know about Chief:  The terrain base height is not set relative to the first floor.  This setting is in the terrain dbx, but it's actually the opposite.  The first floor height is set relative to the terrain.  "Building Pad" means default first floor subfloor.

 

So - to have your garage slab stay correctly located relative to the terrain, here's what we do, that works perfectly every time:

1. Your first floor is at 0".  (And btw, this will mean you will NOT be fighting with room ceiling and floor heights for the duration of the project).
2. Set your garage slab at whatever distance it needs to be from that.  Let's say 30".  You can do this before or after building the foundation.
3. Set your terrain to match.  So if your garage slab is at -30", your "Building Pad" will be at +30"  (because it's the distance the first floor is above the terrain).
4. If you have any terrain modeling, put a flat Terrain Elevation Region at the garage doors.

This file has a quick example:  reliable garage and terrain heights.zip

[HumbleChief]

What he said.

 

At the expense of repeating myself - you will almost always be better off using Chief the way it was designed to be used.  

 

To understand how Chief is designed to work, do this quick exercise:

Start a new plan using the default template (profile.plan).  Draw a simple first floor with an attached garage.  Assign the garage to be the room type "garage" and then let Chief build a foundation using the Floor Tools.  If you now look at the garage room dbx you'll see that Chief has automatically dropped the garage slab.  That's the way it's designed to work.  You can change the amount it's dropped it, and it will hold that setting.

 

And another important thing to know about Chief:  The terrain base height is not set relative to the first floor.  This setting is in the terrain dbx, but it's actually the opposite.  The first floor height is set relative to the terrain.  "Building Pad" means default first floor subfloor.

 

So - to have your garage slab stay correctly located relative to the terrain, here's what we do, that works perfectly every time:

1. Your first floor is at 0".  (And btw, this will mean you will NOT be fighting with room ceiling and floor heights for the duration of the project).
2. Set your garage slab at whatever distance it needs to be from that.  Let's say 30".  You can do this before or after building the foundation.
3. Set your terrain to match.  So if your garage slab is at -30", your "Building Pad" will be at +30"  (because it's the distance the first floor is above the terrain).
4. If you have any terrain modeling, put a flat Terrain Elevation Region at the garage doors.

This file has a quick example:  reliable garage and terrain heights.zip

Great advice Wendy and I think if your post shows anything it shows that a person has to develop a strategy that works for them and stick with it.

 

I'm leaning toward the 'set the terrain perimeter/building pad at 0' and adjust the terrain with elevation regions but I can see your strategy working just as well and as long as ones approach is consistent the crazy making should be kept to a minimum.

 

BTW the file you attached had 0k and I could not open it.

[Joe_Carrick]

My approach is a bit different because I very often am working with a site that slopes up or down away from the street.  Depending on the terrain, the Garage may be at the lowest level, an intermediate level or the top level.  I seldom have a basement that's totally below grade - mostly every floor exposed on at least one side.

 

Consequently I set the lowest Floor at "0" elevation and that's my Level <1>.  I really don't care what it's called Basement, 1st Floor, Sunken Grotto, etc.  I then set the Terrain using that Floor as the "Pad".  If it happens to be the Floor that has the Garage then it's pretty much what Wendy described.  However, if the Street and Garage are 20 feet higher then it's a different situation. 

 

So basically what I'm saying is that I always make the lowest usable floor Level <1> and I don't care what I name that Floor.  If it's a 3 story house with the Entry on the Middle Floor I will call that Main Floor Plan and the others Lower Floor Plan and Upper Floor Plan.

 

IOW:

 

Level <0>     Foundation Plan

Level <1>     Lower Floor Plan

Level <2>     Main Floor Plan

Level <3>     Upper Floor Plan

 

Floor Names are just NAMES.  Levels are numbered and Chief has it's own rules.

 

Unlike Scott, I use Level <0> for the Foundation - but I do handle the Foundation Stem Walls in a similar way.

[WendyatArtform]

There are many terrain strategies.

 

Terrain - we've sometimes set it at 0 and used regions for adjustments - perfectly valid.

 

I think my main point is that you leave the house at 0 and make any adjustments in the garage.  Anything else is letting the tail wag the dog, and not in a good way!

 

Let's try again for that file - must have had it still open..

reliable garage and terrain heights.plan

[HumbleChief]

I think my main point is that you leave the house at 0 and make any adjustments in the garage.  Anything else is letting the tail wag the dog, and not in a good way!

That strategy works best for me as well but as illustrated above Joe uses a different strategy. The key is to understand how Chief works/thinks/is designed to work, which is the hard part, then develop a strategy that works for you.

 

Really appreciate you taking the time to post the plan. I learned just a little more.

[dshall]

.........

 

Unlike Scott, I use Level <0> for the Foundation - but I do handle the Foundation Stem Walls in a similar way.

 

I thought I used level zero for the foundation.  I think on the last 500 projects  I have used level zero as the foundation.  

[Joe_Carrick]

I thought I used level zero for the foundation.  I think on the last 500 projects  I have used level zero as the foundation.  

Perhaps I misunderstood one of your videos.  It looked like you were using Level 1.  I will have to review that vid again.

[jbaehmer]

Perhaps I misunderstood one of your videos.  It looked like you were using Level 1.  I will have to review that vid again.

 

In that video, Scott did have it on level 1.  I think Scott does put a standard FDN (when there is only one structure in the plan file) on level 0, but when he has a house that has a walk out basement and a detached garage on the same level, he puts the basement on level 1 so it lines up with the detached garage since the detached garage would be difficult to build almost all of it on level 0.

[Charlie]

Interesting topic for a couple of reasons. First of which - it is one of my projects and J of KY is working on it with me and we have to figure it out.  I have been using CA since V2 or 3 - so I know a tricky situation when I see it.  I try to always look at a project and sort out how to approach it and set it up before I begin.  When this was laid out with garage at floor 1 (this was done since all the terrain elevations were derived from that floor level) I started thinking that then floor 2 (where most of the new construction will occur) will be easier to control if it was floor 1 as it will at 0" floor.  This test plan has garage at floor 0, new additions above will be floor 1.  Terrain data has been adjusted from field measurements to get it relative to the new floor zero (lowered 112.25"). I assumed an 18" engineered floor system at floor 1 and set the floor 0 default floor ht to -112.25" and that gives be the 93 1/2" ceiling ht below (existing block w/ a plate).

Always a different way to get these results in CA, but I wanted to have relatively simple approach nailed down early in these drawings as I do not want to go in later and have to tweak all the room elevations.  This way the lower garage (and there will be another lower garage added next to it) will be easy to control and all the new construction above will be at 0" floor ht, terrain will all be referenced from 0".  If I change floor joist size, I can change the building pad ht.

 

Peters, Tim 2237 Bonnycastle Ave_Existing test 2.plan

[Rashid_Garuba]

I take it all this planning (My current project is "wrong?!) is because we can't change the elevation of an entire building once built?

[HumbleChief]

There's nothing wrong with the approach you're taking. You can use floor 0 for the garage as you clearly illustrate, or you can use floor 1, not important. Sometimes floor 1 will give you some more options than floor 0 and if the garage is on floor 1 then you can add a foundation on floor 0. If the garage is already on floor 0 then where does the foundation for the garage go? - if you need one?

 

Another thing to consider is which floor plans you want to show on the same level. If you want to see the garage and another floor on the same level in floor plan (for whatever reason) then obviously the two areas have to be on the same floor level.

[Joe_Carrick]

I take it all this planning (My current project is "wrong?!) is because we can't change the elevation of an entire building once built?

You can change the "Pad Elevation" for the Terrain.  IOW, you move the Terrain up or down - not the building.

[Charlie]

If I ever have to change a whole floor's elevation, I go in select interior walls and to change to "no room definition" and then select the whole interior area as one room - change your defaults and set to new default.  Then go back and set walls as room def walls.  Can be tricky - do a save as first.

[WendyatArtform]

That strategy works best for me as well but as illustrated above Joe uses a different strategy. The key is to understand how Chief works/thinks/is designed to work, which is the hard part, then develop a strategy that works for you.

 

Really appreciate you taking the time to post the plan. I learned just a little more.

 

bingo, Bingo, BINGO

 

Red highlighting is mine.  You can certainly make a whole lot of other strategies work.  But if you first and thoroughly learn the program the way it was intended to be used - then when you go cowboy, you'll know where you're going and how to get back if you need to.

 

It's like music.  Before you improvise, learn to sing the tune.  Otherwise instead of cool jazz, you're just out of tune.

 

So when I see a question that's kinda clearly from someone still learning, I head right back to basics.  I think about getting it done in a reliable way rather than "could" they do it some off-label way.  I'm all for off-label uses of the program - (Chief dudes can attest to that!).  But I'm not going to lead a newbie down that path if they're then not going to know how to make all the other adaptations, or even what caveats to put in subsequent questions, like "oh by the way, I put my first floor in the basement"

[WendyatArtform]

I take it all this planning (My current project is "wrong?!) is because we can't change the elevation of an entire building once built?

 

Nope - not what it means at all.  But you don't "change the elevation of an entire building", you change the elevation of the terrain relative to your building.  You just open up your terrain and change that "Building Pad" number.