ACA Structural Member Styles - Part 3A

First Article in the Series (Structural Member Catalog)
Previous Article in the Series (Manually Created Structural Member Shapes)

Manually Created Structural Member Shapes - Fun Facts
Here are a few additional items of interest related to Structural Member Shapes that I have discovered as I was experimenting for the next main article in this series.

1. In order to maintain maximum sanity, set the UCS to World and use the Plan command to orient the screen so that the X-axis is left and right, with positive in the right direction and the Y-axis is up and down, with positive in the up direction. In limited experimentation with a single, 2D polyline as the shape, it appears that the shape will be imported with the World Y axis (or its equivalent, if the plane of the polyline is not parallel to the World X-Y plane) running vertically in the dialog, with positive being up. For example, if you start with the World UCS and rotate the UCS about the Z-axis, that rotation is ignored when bringing the shape into the dialog. When selecting the insertion point, the values of the point selected in the current UCS are used, but are applied relative to the World UCS. In other words, ACA does not translate the insertion point picked from the current UCS to the World UCS, so the insertion point can end up in a very unexpected location, unless it is 0,0 and 0,0 is the same in both the World and current UCS. Someone with a better head for three-dimensional geometry than me may be able to deal with this, but for me, best practice will be to start out with UCS set to World and the screen oriented to the Plan view of the World UCS.
2. 2/10/2012 UPDATE: The following comment only applies to a Structural Member Style that has a single Structural Member Shape assigned to a single component. Insertion points do matter when more complex styles are created.
   When assigning a Structural Member Shape to a Structural Member Style, the insertion point selected for the Shape will not necessarily be on the longitudinal axis of the Structural Member. For Medium Detail and High Detail, the shape is intially aligned at the "midpoint", with the midpoint being the point whose X-coordinate is the average of the shape's smallest and largest X-coordinate values and whose Y-coordinate is the average of the shape's smallest and largest Y-coordinate values. Even if you intentionally offset the High Detail insertion point from the Medium Detail insertion point, both will come in with the midpoint of each at the longitudinal axis of the Structural Member. The selected insertion point does matter for the Low Detail geometry, which does not have to be a closed shape and can have lines and arcs. Low Detail geometry will be placed such that its selected insertion point remains aligned with the selected insertion point of the Medium Detail geometry.

ACA Structural Member Styles - Part 3

First Article in the Series (Structural Member Catalog)
Previous Article in the Series (Structural Member Wizard)

Manually Created Structural Member Shapes
For those times when you want to create a Structural Member Style that does not have a standard cross-sectional shape, you will need to manually create the Structural Member Shape Definition and then add it to a Structural Member Style.

If you enjoy working from prompts on the Command: line, then you can use the
-AecsMemberShapeDefine command to do so. I find it easier to use the Style Manager, so that is the method that will be shown here. Before we dive into creating a custom Structural Member Shape Defintion, lets take a look at one, so we understand how it works. Structural Member Shapes support three levels of detail: Low Detail, Medium Detail and High Detail. Low Detail graphics can consist of lines, arcs, cirles or polylines. The image below shows the W24x76 Member Shape Definition (created from the Structural Member Catalog in Part 1 of this series) on the Design Rules tab in the Style Manager. This tab features a viewer pane that shows the cross-sectional geometry associated with this shape. Selecting Low Detail in the upper right corner highlights the Low Detail geometry in green; the Medium and High Detail geometry remains visible in the viewer, in white. A small "x" indicates the insertion point for the shape. As always, click on any image to see a full size version. If your browser replaces the current page with the image, use the Back button to return here.

Low Detail is intended for small-scale drawings, such as overall floor plans, where representing a wide-flange shape by three lines would be an appropriate level of detail.

The Medium and High Detail graphics have to be closed polylines, splines, elipses or cirlces. You can have more than one of these objects, but they cannot intersect each other, nor can they self-intersect. The Medium Detail graphics for the W24x76 Member Shape Definition consists of a single closed polyline showing the overall size and thickness of the web and flanges, and is appropriate for medium scale representations.

The High Detail graphics for the W24x76 shape also consist of a single, closed polyline, but differ from the Medium Detail graphics in that the fillets between the flanges and the web are shown. This would be appropriate for a large scale representation of the shape.

Each Structural Member Shape Definition must have Medium Detail geometry assigned. The Medium Detail geometry will be used for shapes where geometry is not specified for the Low Detail and/or High Detail conditions. For simple shapes, such as a circular column, assigning geometry to just Medium Detail may be appropriate. A square shape (with a side of 1'-0" for imperial units or 300 mm for metric units) is initially assigned when you create a new Structural Member Shape Definition, so be certain to replace that with the desired geometry. In the out-of-the-box Display Representations for Structural Members, the Structural Member Shape is used for the "Visible Comp n", "Hidden Comp n" and "Component n" Display Components, where n is an integer from 1 to 10. (Structural Members offer display control for up to 10 different components.) The Display Representation that have "Low" in the title use the Low Detail shape. The Display Representation that have "High" in the title use the High Detail shape. All others use the Medium Detail Shape. ("Logical" is a special case, which does not display any of the shapes.)

In the following example, a Structural Member Shape Definition will be created for eventual use in a Structural Member Style that will represent an architectural column cover. A simple circle will be used to represent the cover for Low Detail. In Medium Detail, two circles will be used to show the outside and inside faces of the cover. For High Detail, a closed polyline will represent the detailed profile of the cover. You will need to create the necessary geometry for your shape first, then assign it to a definition.

On the Manage ribbon tab, on the Style & Display panel, select the Style Manager tool. In the left pane of the Style Manager, expand the Architectural Objects and Structural Member Shape Definitions nodes under your current drawing and then select the Structural Member Shape Definitions node. In images below, I have selected the Filter Style Type tool (funnel icon) in the toolbar at the top of the Style Manager dialog to show only Structural Member Shape Definitions. In the right pane, right click and choose New from the context menu. Enter an appropriate name for the new definition - the example definition is called Fluted Column Cover.

In the left pane, select the name of the new definition. Select the General tab in the right pane, and add a more detailed description and, if you want, notes for this definition.

In the left pane, select the Design Rules tab. Take a look at the upper right corner, in the Shape Geometry area. The caution icons in front of the Low Detail and High Detail choices indicate that no geometry has been assigned. As mentioned above, there is already default geometry assigned to Medium Detail for the shape, and the preview window shows the default square shape.

To assign the right geometry for Medium Detail, make certain that Medium Detail is selected in the Shape Geometry area, and then select the Set From button. This will temporarily hide the Style Manager dialog, and, at the Command: line, prompt you to "Select a closed polyline, spline, ellipse, or circle for an outer ring:". Select the outermost geometry ("ring") for Medium Detail.

After selecting the outer ring, you will see the prompt "Insertion point or [Add ring/Centroid]:". Selecting an insertion point or choosing the Centroid as the insertion point will end the ring selection process. In this example, Medium Detail has a second ring, so choosing the Add ring option is appropriate. Continue to choose the Add ring option and select rings until all rings have been selected, and then select an insertion point or use the Centroid option to set the insertion point at the centroid of the selected geometry. This will bring the Style Manager dialog back on the screen, with the newly selected geometry displayed in the preview window.

If you have Low Detail and/or High Detail geometry for your shape, select the Low Detail or High Detail item in the Shape Geometry area and repeat the process of selecting the Set From button and following the prompts. Low Detail will not ask for an outer ring, just lines, arcs, circles or polylines and will not offer Centroid as an option for selecting the insertion point. Make certain that the insertion point for each detail level is the same, relative to the selected geometry. The image below shows the completed Fluted Column Cover Structural Member Shape Definition, with High Detail selected.

You can create a single-shape Structural Member Style that uses your new shape by selecting the Create Style button on the Design Rules tab. The default name for the Structural Member Style will be that of the Structural Member Shape Definition; you can edit the name if you want.

The image below shows an instance of the generated Fluted Column Cover Structural Member Style with the Masonry.Stone.Travertine.Cream Material Definition applied, in Realistic View.

Next article in the series (Manually Created Structural Member Shapes - Fun Facts )

ACA Structural Member Styles - Part 2

First Article in the Series (Structural Member Catalog)

Structural Member Wizard
Sometimes you need a Structural Member Style for a standard shape which is not in the Structural Member Catalog. Or perhaps it is early in the design process, and you have an approximate size for a steel shape, but not an exact size. Rather than pick an exact section, you would like to create a generic member as a placeholder until the structural design is finalized. For these cases, the Structural Member Wizard can speed the creation of the necessary Structural Member Shape Definitions and Structural Member Styles. Access the the Structural Member Wizard on the Manage ribbon tab, by selecting the title of the Style & Display panel to expand the panel and choose the Structural Member Wizard tool on the flyout.

The Structural Member Style Wizard dialog has three "pages". On the first page, you select the Member Shape, from a list of standard shapes in three categories: Concrete, Steel and Wood.

The left pane of the dialog shows a schematic sketch of the standard shape selected, and indicates the dimensions over which you will have control. The illustrations that follow are based on the Steel, Wide Flange (I) shape, but all work in a similar manner.

With the desired member shape selected, select the Next button to advance to the second page, where you will enter the dimensions that will be applied to the Member Shape to be generated.

Most of the values will be shown on the sketch in the left pane; any that are not, such as E - Weld Radius, should be evident from the description. In this case, the Weld Radius is the radius of the fillets between the web and flange. When the values are set as desired, select the Next button to move on to the third page.

On the third page, you specify a name for the Structural Member Shape Definition and Structural Member Style to be created. The page also gives you a summary of the shape type and associated parameters, with the values you entered. Review these to verify that they are correct. You can use the Back button to return to either of the previous screens and make any changes, if needed. When you are satisfied that all values are correct, select the Finish button on the third page to generate the definition and style.

You can check what was created by opening the Style Manager (on the Manage ribbon tab, on the Style & Display panel, select the Style Manager tool). Under the current drawing in the left pane, expand the Architectural Objects node, and then expand both the Structural Member Shape Definition and Structural Member Styles nodes. You will find that a shape definition and a style using that shape definition have been created using the name you specified and the Member Shape selected and the geometric information entered in the dialog.

Next article in the series (Manually Created Structural Member Shapes)

ACA Structural Member Styles - Part 1

AutoCAD^® Architecture provides a number of ways to create Structural Member Styles. This series of articles will take a look at the various options.

Structural Member Catalog
If you are trying to create a Structural Member Style for a standard steel section, or for a typical concrete or timber member, you will want to make the Structural Member Catalog your first stop. The parameters for standard structural members, both Imperial and Metric, are already stored in the Structural Member Catalog, waiting for you to make use of them. Access the the Structural Member Catalog on the Manage ribbon tab, by selecting the title of the Style & Display panel to expand the panel and choose the Structural Member Catalog tool on the flyout.

The Structural Member Catalog is composed of three main sections.

1. The upper right pane will display an image related to the part of the catalog you are currently viewing.
2. The left pane is the navigation pane. By expanding the appropriate nodes in the tree structure, you can drill down to the part of the catalog that contains the member of interest.
3. The lower right pane displays the data associated with the node selected in the left pane. While in the upper level nodes, you can also double-click on an item in the lower right pane to open that node and see its contents.

For example, suppose you needed to model a W24x76 steel beam. In the left pane, expand the Imperial, Steel, AISC and I-Shaped nodes, and then select the W2n, Wide-Flange Shapes item. You will see a list of the AISC wide-flange steel shapes from W21x44 to W27x258 in the lower right pane. Scroll down in that pane until you see the W24x76 member.

Now comes the really hard part. Right click on the the W24x76 member, and choose the only item on the context menu, Generate Member Style.

In the Structural Member Style dialog, give the Style a name. The name defaults to the designation for the member, in this case W24x76.

Once you are satisfied with the name, click OK. You can create as many additional Structural Member Styles as you need. When you are finished, close the Structural Member Catalog by clicking on the "X" in the upper right corner.

You can check what was created by opening the Style Manager (on the Manage ribbon tab, on the Style & Display panel, select the Style Manager tool). Under the current drawing in the left pane, expand the Architectural Objects node, and then expand both the Structural Member Shape Definition and Structural Member Styles nodes. You will find that a shape definition and a style using that shape definition have been created using the name you specified and the geometric information stored in the catalog.

Next article in the series (Structural Member Wizard)

ACA: Model Views and Annotation Scale

I made an interesting discovery yesterday, that may explain why I have occasionally had issues with viewports where the viewport scale and the annotation scale for the viewport are different. I suppose most people are a little more laid back than I am, and tend to draw on the Model "tab" without a lot of regard for how things will end up on the final sheet, and then compose the sheet on a Layout "tab" by eyeballing the corner points of the viewport, pan model space to get the target area roughly centered, use the scale control to set the viewport scale and then pan and/or adjust the viewport extents to suit. I like to think about how what I am drawing will eventually appear on a sheet, and work out how much of a sheet will be required for the drawing at hand. This often results in a non-plotting polyline in model space defining the extents of a particular drawing or detail, and I generally create a Model View of those extents, so that I can later create a viewport of the corresponding dimensions and restore that Model View and be done.

Yesterday's discovery was that I finally noticed that Model Views retain the annotation scale that is current at the time the Model View is created (when using the VIEW command). I did this while using ACA 2010; it may also occur in 2008 and/or 2009.

In the image above, you can see a Model View that I created of the area bounded by the yellow rectangle. This area is intended to be shown at 1/2" = 1'-0" (1:24) on a sheet. I "forgot" to change the annotation scale from the initial default of 1/8" = 1'-0", however, and so the Annotation Scale property of the Model View is 1/8" = 1'-0".

After drawing an appropriately sized viewport on a Layout tab and using the VIEW command to restore the Model View I created in that viewport, the viewport scale is correctly reported as 1/2" = 1'-0" on both the Viewport Scale control on the Drawing Window Status bar and on the Design tab of the Properties palette.

The Properties palette also reveals that the annotation scale associated with that viewport is the 1/8" = 1'-0" that was saved with the Model View. In most cases, having different viewport and annotation scales is not desirable. Note also that if you restore the Model View on the Model tab, the annotation scale will also be changed to that saved with the Model View. If the area is meant to be plotted at a particular scale, having that scale saved with the Model View would help automate getting the right scale associated with annotative content added as well as getting the the right scale when restoring the Model View in a viewport. So I am making a mental note to try to remember to set the annotation scale prior to creating a Model View. But can a Model View created with an incorrect annotation scale be fixed?

Unfortunately, the View Manager dialog does not provide a way to change the Annotation Scale property once the a Model View is created. You can rename the Model View, update the layer snapshot saved with the view (if any) and edit the boundaries of the Model View, but, as you may be able to tell from the gray background in the first image, the Annotation Scale property is not editable. I had hoped that while editing boundaries, that I would be able to change the annotation scale using the control on the Drawing Window Status bar, but that control is disabled when editing boundaries. In order to change the scale, you have to recreate/redefine the Model View, with the correct annotation scale set current prior to the redefinition. This is a fairly straightforward process, but it does require you to reselect the Model View boundaries.

1. With the Model tab current, set the desired annotation scale.
   
2. Start the VIEW command. In the View Manager, select the Model View to be recreated in the left pane, and then select the Name in the middle pane and copy the name to the clipboard. (You can skip this step if you are willing to type in the exact view name in the next step.)
   
3. Click the New button. In the New View / Shot Properties dialog, paste (or type) the view name in the top edit box. Make any other changes to the settings in the dialog as desired.
4. Click the Define view window button (or select the Define window radio button) and define the area of the Model View.
   
5. Click OK in the New View / Shot Properties dialog. Choose Replace in the View - Already Exists dialog.
   
6. In the View Manager dialog, note that the Annotation Scale property for the redefined Model View now matches the current, desired annotation scale.
   
7. Click OK to dismiss the View Manager and register your changes.
8. Return to the Layout tab and restore the redefined Model View in the viewport. Notice that now that the correct annotation scale is associated with the Model View, the viewport gets the correct annotation scale when the Model View is restored.
   

ACA - Multiple Cut Planes in One Sheet

You may have a situation where you would like to show the same plan area more than one time on the same sheet, with the same Display Configuration, but with two different cut planes. For example, you might have a door with sidelights and transom, and you might want to show a plan view cut at the usual cut plane height, through the door, along with a plan view cut through the transom.

This can be done, but you need to remember that the cut plane height is set in the Display Configuration. Recent releases of ACA have had a control on the Drawing Window Status bar that lets you change the value of the cut plane without having to edit the current Display Configuration through the Display Manager.

Someone unfamiliar with the way the cut plane is set in the Display Configuration might think that you could set up two viewports of the same plan area

and make model space active in one and simply change the cut plane for that viewport. Because both viewports use the same Display Configuration (High Detail in the example shown), using the Cut Plane Control to change the cut plane height in one viewport

changes the cut plane in both viewports.

Changing the cut plane back to 3'-6" will, of course, change it back in both viewports. In order to have different global cut planes for the two plans, you will need to have two separate Display Configurations. This is easily done in the Display Manager:

1. With model space in one of the plan viewports active, on the Manage ribbon tab, on the Style & Display panel, choose the Display Manager tool.
   
2. In the left pane, select the Configurations node under the current drawing.
3. In the right pane, right click on the current Display Configuration, which will appear in bold type, and choose Copy from the context menu.
   
4. In the right pane, right click in the white area below the list of Configurations and choose Paste from the context menu.
   
5. In the left pane, expand the Configurations node and select the copied Display Configuration - in the expample, High Detail (2).
6. In the right pane, on the General tab, rename the Display Configuration with a more meaningful name, if desired.
   
7. On the Cut Plane tab, set the desired Cut Height for the cut plane of the new Display Configuration.
   
8. Click OK in the Display Manager to accept the changes and return to the drawing.
9. Set the new Display Configuration current in the plan viewport where you want the new cut plane applied.
   

Because the two viewports now use different Display Configurations, the global cut planes can be different.

Multi-Sheet Plans and Revisions in Revit

Many projects have floor plans that end up being too large to fit on one Sheet. Revit makes splitting a single Level onto two or more Sheets fairly easy by setting up a Dependent View for each sector of the overall floor plan. Revit even includes a Matchline tool to make it easy to designate the extents that each Dependent View documents. Each Dependent View is then placed on its own Sheet.

When choosing where to break up your plan, and how far beyond the matchline each Dependent View should depict (model and annotation), keep in mind that Revit will automagically add a revision to the Sheet if a View on that Sheet contains the full extents of a revision cloud in that View. If you only place revision clouds on the Sheet itself, you have no worries. But for plan revisions, I prefer to place the revision clouds in the View, so there is no need to worry that the View will move on the Sheet without the revision cloud also moving.

If you show large areas of the model beyond the matchline or if the annotation crop extends well beyond the matchline, you are increasing the odds that a small cloud drawn on the View of one Sheet, but near the shared matchline, will also fall completely within the adjacent View's annotation area. If you are issuing both Sheets, that is not a big deal. But if you are only issuing the Sheet that actually has the revision, you would not want the revision to show up on the adjacent Sheet. Keeping things as tight to the matchline as possible will minimize the chance that this will occur.

Sometimes the way the project is laid out makes it difficult to establish a clean matchline to which you can closely crop the Dependent Views. Other times, a revision is relatively small and right next to the matchline. Here are a couple of ways to avoid having the revision show up on the adjacent Sheet.

1. If you have additional revisions in the same View, you can combine the cloud of the revision near the matchline with one that is farther away, and beyond the annotation area of the adjacent Sheet's View.A revision cloud does not have to consist of a single, closed loop of revision arcs. It can be open, and can also have multiple, unconnected runs of arcs. If any part of the graphics of a revision cloud is beyond the annotation area of a View, it will not show in that View, and will not result in a revision line on the Sheet on which that View is placed.
2. If you do not have additional revisions, you can edit the revision cloud to include a very small arc that does not fall in the annotation area of the adjacent View, in a discreet location in the View with the revision. If the graphics this generates disturbs you just as much as having a revision line on a Sheet that was not issued, and you turn off the display of revision clouds from previous revisions when making the next revision, you can wait until after you have printed the drawings to be issued, and then go back and add the small segment just before marking the revision as issued and turning off the display of the revision clouds for that revision.

Rounding and Column Totals

If you have a Schedule Table column that displays real-number values that are rounded by the applied Property Data Format and you also display a total for the column, you may find that the total displayed does not equal the sum of the individual numbers displayed. This can happen because ACA uses the real-number values before the format is applied when calculating the total, and then applies the Property Data Format to the result. So if there is not a balance between round up amounts and round down amounts, the total can differ from the sum of the displayed, rounded numbers.

If this bothers you (it bothers me), you can make use of the same techniques discussed in this blog article, where the task was to get rows with apparently similar values to collapse into one row in a Schedule Table with a Quantity column. The rows were not collapsing because even though the displayed, rounded numbers were the same, ACA was using the actual values, before applying the Property Data Format, to determine whether or not the values were the same.

In response to an inquiry in the Autodesk ACA Discussion Group, I posted a sample file (AutoCAD 2010 format) demonstrating several ways a Formula property can be used to make the source value the same as the rounded value, so that the total for the column will be the sum of the displayed values (and, if you have a Quantity column, that rows with identical displayed values will collapse). The image below shows the test Schedule Table I set up to show how the various properties in the SpaceObjectAreas Property Set display. The file was created using the Aec Model (Metric Stb).dwt template and the AutoCAD Architecture (US Metric) profile.

The columns in that Schedule Table display two properties from the out-of-the-box SpaceObjects Property Set Definition: Name and Number. The remaining columns display properties from a custom Property Set Definition called SpaceObjectAreas. Here is a description of these properties, and the effect that the way they are set up and formatted has on the values displayed and the column total.

• BaseAreaUnformatted: This property, displayed in the column titled "UNFORMATTED", uses the Automatic Base Area property of Spaces to display the area of the space. A custom Property Data Format called Standard-8 has been applied to this property and to the column in the Schedule Table. This is a copy of the out-of-the-box Standard Property Data Format, with the real-number precision changed to eight decimal places and trailing zero supression turned off. There is also no prefix or suffix applied to the value, so when referenced by formula properties, the value will be treated as a numeric value. The areas of the test spaces do not generate any rounding issues when totalled, as they do not require more than the eight digits displayed.
• BaseArea: This property, displayed in the column titled "AREA FORMAT", also uses the Automatic Base Area property of Spaces. It has the out-of-the-box Area Property Data Format applied to it, which in its metric version displays real numbers using an Area unit type, units of square meters, decimal unit format with two-decimal-place precision and a suffix of " M2". Other than Space 101, the area of each space is rounded up when displaying the value to two decimal places. The total is rounded based on the total of the raw values (see the Unformatted column total), and results in a column total that is 0.04 M2 less than the total of the displayed numbers.
• BaseAreaPassThrough: This property, displayed in the column titled "PASS THROUGH", is a Formula property. It takes the BaseArea property and uses the feature added in ACA 2007 that allows you to assign a different Property Data Format for the purposes of the Formula property. In the example file, a custom Property Data Format called Standard-2 is assigned, which is a copy of the out-of-the-box Standard Property Data Format, with the real-number precision changed to two decimal places and trailing zero suppression turned off. The Formula takes the value of BaseArea (rounded to two decimal places by the Standard-2 Property Data Format), makes it a string, converts that to a double-precision real number and passes it through as the final value. Since we want to have a total value for the column, using the default Area Property Data Format would not work, since this includes a suffix of " M2", which would cause the value to be interpreted as a string and therefore not provide a numeric value that can be totaled. Because the Property Data Format has trailing zero suppression turned off, the CDbl conversion is not required, but because I know this value should always be a number, I put it in, should the Property Set ever get copied to a file that already has a Property Data Format called Standard-2 that has trailing zero supression turned on. In that case, if the BaseArea value was a whole number, the result would be interpreted as an integer in ACA and the real-number formatting would not be applied.
  
  Because the Formula property is generating the "raw" values with the area values rounded to two decimal places, the column total reflects the total of the actual values displayed, rather than the rounded sum of the source areas of the actual Spaces.
• BaseAreaRounded_01: This Formula propery is displayed in the column titled "FORMULA ROUNDING 0.01". It accomplishes the exact same effect as the pass-through Formula, but uses the VBScript Round function to do so. CDbl( Round( [BaseArea], 2 ) ) It also assigns a different Property Data Format to the BaseArea property (Standard-8, in this case). In the example file, I could have simply referenced the BaseAreaUnformatted property without reassigning the Property Data Format in the Formula property, but I used the BaseArea property with the reassigned Property Data Format to demonstrate that you do not need to set up a separate, unformatted version of an automatic property if you are using the 2007 or later version. I included the unformatted property here so that I could display the area values to eight decimal places in the Schedule Table, so you could see the effects that the various formatting/rounding options had on the raw numbers. As with the previous formula, the column total matches the sum of the displayed values, because the raw value of the Formula property is the same as the displayed value. If you can achieve the precision and rounding you want with a Property Data Format, then you can use either the pass-through or the Round function method. As you will see in the final example, the Round function (combined with other mathematical operations) can do things that the Property Data Format cannot do, in which case the Round function would be the only choice.
• BaseAreaRounded_05: As seen in the column titled "FORMULA ROUNDING 0.05", this Formula property rounds the area value to the nearest 0.05, and since the raw values are the actual rounded values, the column total is correct for the displayed values. CDbl( Round( ( [BaseArea] / 0.05 ), 0 ) * 0.05 ) The formula achieves the desired rounding by starting with the BaseArea property value, with the Standard-8 Property Data Format applied. It divides that value by 0.05, rounds the result to the nearest whole number and finally multiplies that result by 0.05 to achieve the desired result. I am not certain how often something like that might be used in a metric file (you could use the same technique to round to the nearest half-square meter, just change the "0.05" to "0.5"), but there are occasions, when using imperial units, that rounding room areas to the nearest 25 or 50 square feet is used as a means of not implying too much precision in early test fits.

In all of the Formula properties, the Area Property Data Format is applied to the property (and the column in the Schedule Table) to get the " M2" suffix applied to the value calcuated by the formula. Also remember that when specifying a property reference in a Formula property, you have to select the referenced property from the Insert Property Definitions box in the lower left corner of the Formula Property Definition dialog; you can not simply type in the name of the property, enclosed in square brackets. If you are interested in reading more about rounding in Formula properties or some of the other techniques discussed above, you may want to check out some of these earlier blog articles:
07/09/2005 - Unformatted Properties and Numeric Precision
08/31/2005 - Rounding Up Property Data Values
08/31/2005 - Rounding Revisited
09/03/2005 - Rounding Redux
09/15/2005 - Rounding to Death
05/01/2006 - Using Property Data Formats to Force Real Number Interpretation
04/15/2007 - ACA 2008/ADT 2007: Setting a Different Property Data Format in a Formula Property
06/16/2007 - Rounded Values and the Quantity Column

Revit Key Plans - More Detail

It has come to my attention that my Revit Key Plans article can be hard to follow, particularly if you are not familiar with some of the concepts or procedures used. It was not intended to be a step-by-step tutorial, so I am providing this post to fill in some of the gaps and make it easier to follow along. This tutorial was prepared using Revit Architecture 2011; interface elements in other versions or releases may vary.

1. Start a new Generic Annotation Family. From the Application Menu - Big "R" in the upper left corner - choose New > Family. In the New Family - Select Template File dialog, navigate to the folder where you or your firm have placed the Annotation Family Templates, and choose Generic Annotation.rft.
2. Determine how your Key Plan needs to function. I do not want to have to place the Key Plan family separately on each Sheet; I want it to be part of the title block family so that it need only be placed once, and will always be in the exact same position on each Sheet. I also do not want to set up a title block family type for each Key Plan option. I do not want to show a Key Plan on every sheet in the set, so I will need a Key Plan type that shows nothing at all. There will be plans that show the overall building, as well as larger scale plans showing only one of the two wings. I want a solid fill to show in the Key Plan indicating the area that is being shown on that drawing. I also want to be able to show the Key Plan outline graphics with no fill.
3. Create the graphics for your Key Plan. You are going to have to figure this one out on your own. There does not appear to be a way to make use of any sort of graphics in a project file and transfer them to a family file. You can scale graphics inside the family, so you could draw the building outline in the family to scale and then scale it down to fit the area available in your title block for your Key Plan. As shown below, I created scaled-down outlines of the two wings of my building and then added text to identify the wings, filled regions with solid black fill for each wing, and the north arrow graphics. Keep in mind that the intersection of the two reference planes will be the initial insertion point for your Key Plan family and position your graphics accordingly.
   
4. In order to be able to control the display of the various graphic components, I created three type-based Yes/No parameters in the Family Types dialog. The first is for the outline, text and north arrow graphics that will be on whenever a Key Plan is to be displayed, but off when no Key Plan is to be shown. I called this parameter Outline.
   1. On the Modify ribbon tab, on the Properties panel, select the Family Types tool.
      
   2. In the Family Types dialog, click on the Add button in the Parameters area at the lower right side.
      
   3. In the Parameter Properties dialog, in the Parameter Data area, enter the name for the parameter, change the Type of Parameter to Yes/No, select a parameter category under which to group the parameter - I used Graphics and select the Type toggle. Click OK to add the parameter and dismiss the Parameter Properties dialog.
      
   4. In the Family Types dialog, I cleared the check mark in the value column, so that the current condition will be to not display the graphics.
      
      Repeat the previous sub-steps to add the remaining two parameters, SectorA and SectorB, for the filled regions associated with each building section. Other than the Name, the parameter attributes are the same as those for the Outline parameter. Uncheck the toggle in the value column for these as well.
      
5. With the Family Types dialog still open, create a family type for each display condition you want for your Key Plan, and turn on the appropriate visibility parameters for each type. In the example, I created five: No Key Plan (all parameters unchecked), Outline Only (only Outline parameter checked), Sector A (only Outline and SectorA checked), Sector B (only Outline and SectorB checked) and Sectors A-B (all three checked).
   1. In the Family Types dialog, select the New button in the Family Types area at the upper right.
      
   2. In the Name dialog, enter the name for the Family Type in the Name edit box and click OK to register the entry and dismiss the dialog.
      
   3. In the Family Types dialog, set the appropriate value (checked or unchecked) for the visibility parameters for this type. (For the No Key Plan type, leaving all unchecked is correct.)
      
   4. Repeat the preceding sub-steps to add the remaining Family Types needed for your Key Plan, setting the appropriate values for each type.
      
6. Select all of the graphic elements in your Key Plan that are to be associated with one of the parameters (in my example, I started with the Outline parameter, to which everything but the filled regions will be assigned). On the Properties palette, look for the Visible parameter, under the Graphics parameter group. If you do not see it, you likely selected an object, such as a Reference Plane or a Group, which does not have this parameter. Deselect these items. Select the button at the right side of the Visible parameter line. (In versions prior to 2011, do this from the Instance Properties dialog for the selected items.)
   
7. In the Associate Family Parameter dialog, choose the appropriate Yes/No parameter (Outline, for the graphics selected on the first pass) and then click OK.
   
8. Notice on the Properties palette, the Visible parameter and its value are now grayed out and the button at the right side displays an equals sign ("="). This indicates that the Visible parameter has been linked to another parameter, and cannot be edited directly. You can click on the button to verify (or edit) the chosen parameter.
   
9. Repeat the previous three steps to assign the SectorA and SectorB Yes/No parameters to the visibility of the associated graphics (in my example, the filled regions). Note: If you have any Detail Groups within your Key Plan Graphics, as I did to collect the various parts of the north arrow graphics, you will need to edit the group to be able to assign the appropriate visibility parameters to the nested graphics within the Detail Group.
10. At this point, your Key Plan family is complete. Save the family.
11. Open the Title Block family into which you will place the Key Plan. Load your Key Plan family into the title block family. (One way, with the Key Plan family open and current, on any of the standard ribbon tabs, on the Family Editor panel, choose the Load into Project tool. If you have multiple potential target files, choose only your Title Block family in the dialog presented.)
12. Your Title Block family should be set current and you should be prompted to insert an instance of the Key Plan family. If you are not seeing any "ghost" graphics of your Key Plan family near your cursor, check the Properties palette to see what the default family type is. Mine was set to No Key Plan, which has no visible graphics, so I got no ghost graphics to aid in initial placement. I changed it to Sectors A-B so that I could see all of the graphics.
    
13. Adjust the location of your Key Plan family in your title block, if necessary.
    
14. Select the placed instance of the Key Plan.
15. On the Options Bar, click on the down arrow at the right of the Label drop-down and choose <Add parameter...> from the list.
    
16. In the Parameter Properties dialog, in the Parameter Data area, give the new parameter a name; I used Key Plan. Choose a Group for the parameter; I used Graphics once again. Make this parameter an Instance type. This is crucial, as doing so will allow each instance of your title block to have a different family type displayed, which is what you want.
    
17. On the Home ribbon tab, on the Properties panel, click the Family Types tool.
18. You should see the Key Plan (or whatever your called yours) Label listed as a parameter under the Graphics group (or whatever group you chose). Set the value for the Label to your desired default Key Plan family type. This is the value that newly created (or newly updated) title block instances will use. I chose to set mine to No Key Plan. (If your Title Block family has several family types, you will want to do this for each Family Type. This only sets the default value; each instance can be changed to show a different Key Plan type because we made the Label an instance parameter. This avoids the need to create a separate Title Block family type for each Key Plan type.)
    
19. Save your Title Block family file.
20. Load or reload your Title Block family into a project. On a Sheet that has an instance of this Title Block family, select the instance.
21. On the Properties palette, notice that, under the Graphics parameter group (or whatever parameter group you assigned to the Label applied to the Key Plan instance in your Title Block family), there is now a parameter called Key Plan, the value of which is a drop-down list of the family types you created in your Key Plan family. Choose the type you want to see for that particular Sheet.