Where are these inaccuracies coming from?

[Richard_Morrison]

At the outset, let me say that I love working in Chief for its speed. However, today I noticed that the final plan had gotten off from its initial measurements by a number of inches in a number of places, a couple of inches in some places, up to 5 inches in others. I take very detailed measurements at the start, and drew a fully dimensioned plan of the existing conditions. After some scratching of my head when things weren't quite working out after a number of design iterations, I redrew the plan in Archicad because of its renovation filters, using the same measured dimensions. I exported existing conditions in DWG format from each program, and overlaid the plans on top of each other. They did not line up in a number of locations, and Chief clearly was the one that had gone a little wonky. It's easy to say that I just didn't input things correctly in Chief when I first drew it, but this is not the first time its happened and I am pretty careful. 

 

I'm wondering if anyone else has had this experience, and has any insight as to why it might be occurring. (It used to be that Chief would move walls to align automatically with other walls, but I haven't seen that behavior in years.) Maybe solutions to preventing this? I hate drawing things twice.

[Alaskan_Son]

I think the discrepancies are likely a result of your specific workflow in Chief.  How are you drawing walls and inputting dimensions?  I personally draw my walls and manually place dimensions as I go so that I know I'm dimensioning to the correct layer and that I've actually already set the wall(s) in question.  Its also imperative that you select the most appropriate wall and use the most appropriate Move settings.  Quick example where the structure should be 16'x14'.  There are 4 different walls a person could select and 2 or 3 different Move settings for each.  You could select the left or right wall and each of the 3 settings would change the dimension to 14' but one would move the top wall upward, one would move the bottom wall downward, and the other would move both of the aforementioned perpendicular walls....

 

 

That is NOT the wall I would recommend you select though.  I would recommend selecting the wall that you actually want to MOVE not the wall you want to resize.  Its much safer and more predictable this way...

 

Also, as I said previously, I would typically just place the dimensions as I go so I wouldn't have 4 of them like I do in the example, I would likely just have 2.  They represent walls that have been set.  There are other good methods as well and you could even be using the tab input method, but bottom line is that there needs to be a methodical workflow for both drawing the walls and keeping track of which ones you've set and they need to be set in such a way that you're sure to be moving the walls as intended.  It's easy to use the top example and set the dimension to 14' but also inadvertently move the wrong wall.

[lbuttery]

its an old song - but I'll sing it anyways

 

"it would be nice to have wall-room-floor-area locks"

 

Lew

[ricatic]

Richard...thanks for bringing this up. As a relative newbie, I have had this problem bite me more than once. I knew it had to be something in my methods that caused it. I found the damage could be limited by constant vigilance. Subsequently, that vigilance pointed out that the proper use of the provided dimensioning tools so nicely demonstrated by Michael was the real solution.

 

Michael...thanks for all the help you provide...

 

Lew...I have wondered why the options you requested are not available. When I design, I always try to size exteriors  to even number dimensions in 2’ increments. After visualizing a clients ideas and square footage requirements I have a required size ratio in mind...say for example 28’ by 44’. I draw the walls and want them to stay in place...there wandering ways under present conditions is frustrating. We lock roofs... a fair question is “why not walls enter.?”...

 

Regards

 

Rick

 

[lbuttery]

Rick:

 

I have been requesting locks since I started with Chief 9.5 in 2006

 

there has been great resistance from other users and from CA 

 

it is deemed "user error"

 

the chorus to my Lock Song is

 

I don't care if its user error

I really don't care if its user error

LEAVE my walls alone 

 

at a minimum Chief could pop up a warning that a Locked area was going to be changed

this warning could be a user preference item for those who don't want/need such warnings

 

Lew

[Gr8trim4u]

X13 has construction lines. These may help eliminate, or at least provide a lockable layer that will allow you to verify your inputs. I usually create a lockable CAD box for the exterior dimensions on as builds. Our jurisdictions do not trust our as build survey, we have to have the engineering guys site plan. Often times I find discrepancies in their work. The single decimal placement can cause issues over a multiple cornered house. 

 

 

[Richard_Morrison]

7 hours ago, Alaskan_Son said:

I think the discrepancies are likely a result of your specific workflow in Chief.  How are you drawing walls and inputting dimensions? 

 

Michael,

Interesting theory, but no. Over the past twenty-five (?) years of using this program, I have not used your method #1 even ONCE, except for maybe trying it out in beta. I have always moved walls by selecting the wall to be moved, since that was the only method available originally -- and old habits die hard. The usual placement method for me is by using temporary dimensions initially, and then by explicitly placed dimensions later. I am pretty confident that the initial placement is accurate. Somewhere along the process, dimensional creep sneaks in. However, it does occur to me that if the temporary dimension defaults accidentally got changed from surface to dimension layer in the middle of the project, this might introduce some compounding inaccuracies, but I'm not sure how this could happen.

 

I think the best approach right now (which someone mentioned in a thread on measuring existing conditions) is to create room polylines as you go during the initial input, which then act as a "canary in the coal mine" when things get off, as Wendy put it. Adding a transparent fill to them really makes later discrepancies "pop". Now that we can select multiple rooms for group changes, I was hoping that creating multiple room polylines was possible, but it isn't.

 

One of the few things I agree with Lew about is about how lame the layer locking system is. The lock only prevents a user from selecting the wall, it doesn't prevent the PROGRAM from changing it. In fact, you can select all the wall layers and lock them, and then change all of the wall dimensions and appearances in the wall type DBX.

[GeneDavis]

Can you give us an example of dimensional creep?

 

When doing an asbuilt, your measurement tool can give you inaccuracies, but you use Chief to get a plan that is as close to what you can measure.  You have a restraint, in that wall thicknesses have to be gaged somehow, or backed into somehow.  You have a tape or rule or laser that gives a surface to surface reading, that rounds to 1/16".  Somewhere in your scheme, when drawing the plan from the measurements, you have to resolve where to do some rounding.  Where is the creep?  Show us, please.

[Alaskan_Son]

2 hours ago, Richard_Morrison said:

Michael,

Interesting theory, but no. Over the past twenty-five (?) years of using this program, I have not used your method #1 even ONCE, except for maybe trying it out in beta. I have always moved walls by selecting the wall to be moved, since that was the only method available originally -- and old habits die hard. The usual placement method for me is by using temporary dimensions initially, and then by explicitly placed dimensions later. I am pretty confident that the initial placement is accurate. Somewhere along the process, dimensional creep sneaks in. However, it does occur to me that if the temporary dimension defaults accidentally got changed from surface to dimension layer in the middle of the project, this might introduce some compounding inaccuracies, but I'm not sure how this could happen.

 

Okay, then the next places I would look would be these:

 

Your Current Active Dimension Defaults:  Don't forget that your Temporary Dimensions get their rounding behaviors from your Active Dimension Defaults.  Its possible that you're not changing dimensions that appear to be correct when in fact they should be changed because the displayed dimension value is rounded too far.  In other words, if you want to see 14' and your dimensions are rounding to the nearest 1/2" then 13' 11-3/4" would report as 14' and look just fine.  It would however add 1/4" to your compounding problem.

 

Your General Wall Defaults>Resize About setting:  This can be both the source and solution to some of these types of problems.  Depending on how you're drawing your walls, toggling this setting can make accurate placement a lot easier and more intuitive.  This setting also controls how walls get resized so if its set so that your walls are resizing in an unexpected way, it could also cause your dimensions to jump on you.  For example, if you set your walls to resize about the Main Layer Inside during the initial drawing phase and then subsequently change your exterior wall type from 2x4 to 2x6, the overall footprint of your house would increase by 2" in every direction throwing all your dimensions off.

 

Your Wall Direction:  Wall layers can be reversed; either manually or automatically, and doing so can move your dimension ends.  This is just something to be aware of because sometimes--particularly if you JUST placed the dimension recently--it can appear as if though your dimension is wrong when in fact its just measuring the other side of the wall.

 

Your Wall Definitions:  Your various wall layer thicknesses and "Dimension to" settings can play a big role here.  This can be especially true if you are dimensioning to surfaces of walls with unusual layer thickness, when your walls have layer thicknesses that are not 1/32" increments,  when you have multiple main layers, or when your layer thicknesses have a higher degree of accuracy than your dimensions are rounding.

 

Also, just some added tips:

• I personally don't use Temporary Dimensions for initial modeling very often.  They're a little too limiting and don't provide a good way for you to keep track of what you've already set or not set.
• Again, consider toggling the Resize About setting during your modeling process.  This can make it a lot easier to draw walls like you designed them or like you measured them.  Sometimes you may want it to be the Main Layer, sometimes you way want it to be the surface layer, or sometimes you may want it to be the center of the wall. 
• You can use the Tab input method when drawing walls.  This can be particularity useful and accurate when used in combination with the Resize About Setting.
• For your canary-in-the-coal-mine, you can consider starting with a polyline or even using the Input Point tool.  You can then snap your walls to those points.  Again though, that Resize About Setting can make a huge difference here.  Your reference lines/points are only useful if they're snapped to the correct wall layers...and again, the wall layers are only useful of their thicknesses are correct and accounted for.

 

 

[ricatic]

35 minutes ago, Alaskan_Son said:

 

Okay, then the next places I would look would be these:

 

Your Current Active Dimension Defaults:  Don't forget that your Temporary Dimensions get their rounding behaviors from your Active Dimension Defaults.  Its possible that you're not changing dimensions that appear to be correct when in fact they should be changed because the displayed dimension value is rounded too far.  In other words, if you want to see 14' and your dimensions are rounding to the nearest 1/2" then 13' 11-3/4" would report as 14' and look just fine.  It would however add 1/4" to your compounding problem.

 

Your General Wall Defaults>Resize About setting:  This can be both the source and solution to some of these types of problems.  Depending on how you're drawing your walls, toggling this setting can make accurate placement a lot easier and more intuitive.  This setting also controls how walls get resized so if its set so that your walls are resizing in an unexpected way, it could also cause your dimensions to jump on you.  For example, if you set your walls to resize about the Main Layer Inside during the initial drawing phase and then subsequently change your exterior wall type from 2x4 to 2x6, the overall footprint of your house would increase by 2" in every direction throwing all your dimensions off.

 

Your Wall Direction:  Wall layers can be reversed; either manually or automatically, and doing so can move your dimension ends.  This is just something to be aware of because sometimes--particularly if you JUST placed the dimension recently--it can appear as if though your dimension is wrong when in fact its just measuring the other side of the wall.

 

Your Wall Definitions:  Your various wall layer thicknesses and "Dimension to" settings can play a big role here.  This can be especially true if you are dimensioning to surfaces of walls with unusual layer thickness, when your walls have layer thicknesses that are not 1/32" increments,  when you have multiple main layers, or when your layer thicknesses have a higher degree of accuracy than your dimensions are rounding.

 

Also, just some added tips:

• I personally don't use Temporary Dimensions for initial modeling very often.  They're a little too limiting and don't provide a good way for you to keep track of what you've already set or not set.
• Again, consider toggling the Resize About setting during your modeling process.  This can make it a lot easier to draw walls like you designed them or like you measured them.  Sometimes you may want it to be the Main Layer, sometimes you way want it to be the surface layer, or sometimes you may want it to be the center of the wall. 
• You can use the Tab input method when drawing walls.  This can be particularity useful and accurate when used in combination with the Resize About Setting.
• For your canary-in-the-coal-mine, you can consider starting with a polyline or even using the Input Point tool.  You can then snap your walls to those points.  Again though, that Resize About Setting can make a huge difference here.  Your reference lines/points are only useful if they're snapped to the correct wall layers...and again, the wall layers are only useful of their thicknesses are correct and accounted for.

 

 

A question from the relative newbie...What is the "tab input wall drawing method"?...I searched the help files and this forum but did not find any information.

 

Regards

 

Rick

[Richard_Morrison]

41 minutes ago, GeneDavis said:

Can you give us an example of dimensional creep?

Okay, see the attached. When I finished the existing plan, both floors were lined up exactly. Now, while doing the final condocs, I see that they are out of alignment.

[Richard_Morrison]

48 minutes ago, Alaskan_Son said:

Your General Wall Defaults>Resize About setting:  This can be both the source and solution to some of these types of problems.  Depending on how you're drawing your walls, toggling this setting can make accurate placement a lot easier and more intuitive.  This setting also controls how walls get resized so if its set so that your walls are resizing in an unexpected way, it could also cause your dimensions to jump on you.  For example, if you set your walls to resize about the Main Layer Inside during the initial drawing phase and then subsequently change your exterior wall type from 2x4 to 2x6, the overall footprint of your house would increase by 2" in every direction throwing all your dimensions off.

In thinking about this some more, I believe that this is a setting that I have not paid enough attention to, and could be the source of these issues. I have always just left this set to "resize about outside of main layer," because it seemed logical to not want to ever expand the footprint of the house, but on the other hand, when all of the existing dimensions have been taken based on interior finish surfaces, this obviously may not be the best choice.

 

Thank you for getting me to think about this!

[GeneDavis]

You only want to be dimensioning to surfaces when you first draw an asbuilt plan from your field measurements.

 

Imagine the most perfect and useful measuring tool:  a virtual smart bullet, self-leveling, military-class gps on board, data logging, 0.001" accuracy.  Fired through the house at 36" above floor, perfectly level, it passes through a sequence of walls and spaces, recording each.

 

But you can't do that.  Your laser will give you the spaces, and with the right jigs, can give you outside to outside on exterior, but the rest, the wall thicknesses, to the accuracy of your laser for surface to surface spaces (maybe 1/16"?), is harder to get.

 

For an asbuilt to be drawn, I try to find every wall I can, interior and exterior, that can have its thickness somehow measured, and it is almost every time, done using subtraction.  Door frames, trim, moldings, and more, all in the way.  You cannot do forensic chainsaw work to do this, except for walls you know are gonna get demolished.

 

I'll establish those wall types with definitions, ext 1, ext 2, int 1, int 13, whatever, and use those when drawing the plan from the field measurements.  I use wall resizing from exterior surfaces, and I edit walls as needed after a plan is drawn, to get the best combination of walls and spaces to match what that virtual bullet had recorded.

 

And as we all know, the asbuilt house is nowhere near perfectly orthagonal.  Built long ago to a simple plan that called it 24 feet by 40 feet on its frame deck, it's of course out of square.  It's 24'2 on one end and 24'3 on the the other.  And the taper is not linear.

 

So I draw it as best I can with my numbers and wall types, and then make tiny adjustments so the overall length comes either to what I measured, or really close, and it is the walls I play with to do the tuning.

 

Chief doesn't make the mistakes.  I do. 

[SH_Canada]

10 minutes ago, GeneDavis said:

You only want to be dimensioning to surfaces when you first draw an asbuilt plan from your field measurements.

When I do a site visit, I will attempt to take measurements off of one or two reference outside walls, as dimension creep will occur if you do not.i.e 10'+10'+10' is not actually 30'. Essentially I ensure certain critical measurements are accurate, and then move walls to match. It is never perfectly accurate (typically out an inch or two when I compare reference measurements to addtive measurements, but I also round to the 1/4" or 1/2" most of the time), I will move walls in CA, and might even move the exterior wall, maybe up to 2 inches, but it is rare to move an outside wall as I will match it to the survey (with an assumed finish thickeness, i.e. close enough is within an inch). I do a lot of basement renos, which means I will move the interior 2x4 wall in an inch or 2, so in this respect I am lucky to have this leaway for basements. If it is any more than that sometimes I will ask the homeowner to double check for me

 

I also do the math back to stud as I dimension stud to stud. I can double check the original dimensions by looking at the CA room area as it is to finished wall. I did one a couple months ago, and the dimensions were not adding up, the homeowner ended up peeling back some siding and we found some fiberglass batt, about 1.5" on the outside of the walls. weirdest thing. I was also renoing my parents and found one doorway was actually 5" thick instead of 4.5 (and no it wasnt mud). Bizarre.

 

The only time I have seen outside walls move in CA is if I accidently include them as part of a object selection

 

Even if I have changed from 2x4 to 2x6 I have noticed it correctly sits on the outside of my foundation. I have seen a an odd thing on dimensions where I was expecting it to pick up the stud but it picked up the drywall. Ever since then I've been a little paranoid about dimensions, If I remember the other place the behaviour is interesting it top of stair, does it include the nosing or not.

 

renoing is a game of inches so I can empathize with attempting to get the accuracy correct..I've had to detail more than once where interior room door casings are 1.5 at the inside hinge, but 3.5 everywhere else, in trying to recover 2"

[ricatic]

23 minutes ago, solver said:

@ricatic

 

Always best not to clutter another's thread with unrelated questions. Deleting is now via the 3 dots.

We will have to disagree...I believe the question is relevant and related...it is brought up within the discussion by a highly valued member as a possible cause of the OP’s original question...a simple point in the right direction is all I asked for...

 

Regards

 

Rick

[Ridge_Runner]

3 hours ago, Alaskan_Son said:

For example, if you set your walls to resize about the Main Layer Inside during the initial drawing phase and then subsequently change your exterior wall type from 2x4 to 2x6, the overall footprint of your house would increase by 2" in every direction throwing all your dimensions off.

This is the one that has gotten me in trouble in the past. I have learned to watch that setting carefully before I change 2x4 walls to 2x6 (along with the wall main layer side).

[GeneDavis]

3 hours ago, ricatic said:

A question from the relative newbie...What is the "tab input wall drawing method"?...I searched the help files and this forum but did not find any information.

 

Regards

 

Rick

Pressing TAB whenever drag-moving anything, wall, line, symbol, while still holding the left button, opens a dialog box allowing user distance input.  Surely you are using this all the time, right?  Want to move a wall 3 inches right?  Select it, hold, start to drag right, press TAB, and voila! there's your input box in which you type 3.

[ricatic]

1 hour ago, GeneDavis said:

Pressing TAB whenever drag-moving anything, wall, line, symbol, while still holding the left button, opens a dialog box allowing user distance input.  Surely you are using this all the time, right?  Want to move a wall 3 inches right?  Select it, hold, start to drag right, press TAB, and voila! there's your input box in which you type 3.

Gene

 

Thanks for the answer...I do use the tab drag but never associated it with moving a wall...duhhh....

 

Regards

 

Rick

[Alaskan_Son]

34 minutes ago, ricatic said:

I do use the tab drag but never associated it with moving a wall...duhhh....

Its not just for moving objects.  In my post above I was actually referring to using the method to draw the walls...click to start, drag, hit tab, enter distance(s)/direction, hit Enter. 

 

Also, just a side note, but the tab entry method (using the Enter Coordinates dialog) can also be used to accurately move or resize an object to a specific length or distance without even know what that distance is.  Consider the following example:

Let's say you want dimension A to be 12'.  You can simply drag point C so that it snaps to point B, hit Tab, hit the forward arrow, and enter -12' into the dialog....

 

 

Follow that by hitting the tab key and you’ll see how far you actually need to move Point C.  Hit Enter and your desired dimension will be 12'...

[Alaskan_Son]

5 hours ago, Richard_Morrison said:

Thank you for getting me to think about this!

You’re welcome sir.

[ricatic]

Thanks to Michael and Gene I learned a few things today...

 

Regards

 

Rick