Tired of Verifying Code Required Clearances in AutoCAD? Incorporate Them in to Your Dynamic Blocks

No matter what your discipline, one of the tasks of a designer is to make sure that code or ordinance requirements are met. A lot of codes and ordinances incorporate clearance, spacing or directional items that must be complied with.  Verifying compliance is a regular task that could mean embarrassment or possibly a red tag and significant costs if it is not caught in the plans review but does get caught in the field.

Two common code regulatory agencies that have requirements that are perfect for incorporating into blocks are the American Disabilities Act (ADA) and the National Electric Code (NEC).

I have dealt with both myself, and it always adds a little more time than I would like to spend to verify that the necessary clearances are met – especially when plan changes happen.   Now this does not mean I do not want to do this important task, I just want to get it done faster!

In my current field of work, the NEC is what I deal with regularly, and an important concern is that of clearances in front of and around electrical gear. This is a safety issue, and if not met can stop a job in its tracks and possibly cause expensive re-work.

A few years ago I decided to address this by incorporating these clearances in the company’s master blocks. As the blocks got more detailed, they became more useful for not only verifying code clearances but also being able to verify quick electric room layouts.

Visual Clarity

Below is a screen shot of an electrical room without clearances shown.  When looking at this electric room plan, the non-electrical person will often assume the room is too big and has a lot of wasted space, which is something we deal with some building owners and architects.


Figure 1

We don’t want to waste space if possible, but as part of our design, we have to consider, future expansion, ventilation around equipment, and most importantly manufacturer’s and code required clearances.

Below is the same room with clearances turned on.


Figure 2

The clearances shown in Figure 2 above are on a non-plot layer called “E-clearances” (not defpoints).

Note: If you have a bunch of (or any) non-plotting notes and line work on defpoints – please don’t. Defpoints has a purpose, and it’s not for storing your coordination notes and linework.  If you would like an explanation as to why using defpoints is bad, check out the post titled “Layers are a piece of Cake” – my first ever FunctionSense post.

I typically leave this non-plotting coordination layer on as an easy check when there are background changes – to make sure we stay in compliance.

More Useful Data

To make the blocks even more informative, add supplemental data that allows you, your coworkers and any team members that you share your drawings with to stay informed on your design intent. In Figure 2 above, you may notice text in the transformer and clearance lines. The text in the clearance lines lets us know which code situation we fall in based on the voltage and material in front of the gear.  The notes in the transformer tell us what size transformer our layout is based on and how much it weighs in case it needs to be hung from structure.  This may also be helpful for any other team members that we share the drawings with.

Most companies, mine included, use a specific manufacturer as the basis of design.  One of the things I have also started incorporating in manufacturer specific blocks is an additional ‘Visibility State’ that lists the manufacturer’s reference data or specific application notes.

Check out this quick video showing some of the features mentioned above.


There are some pretty cool things you can do to increase your productivity by incorporating code required clearances and other useful data into your dynamic blocks.  Other items we commonly incorporate:

  • Ordinance required light pole spacing (based on pole height – visibility state, plots on drawings)
  • Coverage patterns for Occupancy sensors (based on multiple manufacturers with different colors, non-plot layer)
  • Coverage of Fire alarm strobes based on Candela rating (visibility states, non-plot layer)

Are you incorporating code, ordinance or manufacturer’s data in your blocks for coordination purposes?  If you have a unique idea, I would love to hear about it.  Leave it in the comments or email me.


Are you Ready for Autodesk University 2016?







Autodesk University 2016 (AU) is right around the corner!  Are you registered?  Are you wishing you were? This is my 5th AU and I am definitely looking forward to it. If you have not registered yet, but are intrigued, go here:

Registration info

It would be awesome to meet you at the  event.  If you are going, message me and let me know!

I am currently in the process of writing an article for a special edition of AUGI World that will be distributed at AU. I can’t share everything from the article, but there are a few things that I feel are important for those attending AU for your first time.

Be prepared

What does that mean? Well – do your homework!  Not sure? Check out these posts on surviving and thriving at the annual AU event by some experienced AU veterans below.

This is a list of bloggers that have written AU specific posts as well as links to their sites. When you get to each site, for additional AU topic posts,  just search on the key word “university”.

Get the APP

If you are going and have not done so yet, get the App.


The links above will give you a good intro to what the event is and provide some actionable tips on how to get prepared. If you have questions, I would be glad to help if I can.  You can email me at: walt@functionsense.com or tweet me at @functionsense.

As I said above, let me know if you are going and maybe we can get together for a coffee or a Crown! : )


AutoCAD Anonymous Blocks












In my last post I indicated that I would follow up on a specific issue that I see happening on a pandemic level  – anonymous blocks.

Simple Definition of anonymity: the quality or state of being unknown to most people : the quality or state of being anonymous

Anonymous in AutoCAD basically means unnamed, so an anonymous block is a block without a name. In reality it does have a name, it just does not make much sense.   Below are a couple anonymous blocks – tell me what you think they are:

  • A$C4AE13D6C
  • A$C7227553F

Here is an image of the blocks:

Anonymous Blocks






I am not sure about you, but I am thinking that better names would be:

  • Fire-Extinguisher

I think we would all agree on this, but you may have a few questions:

  • How did these become anonymous?
  • Why is that a problem?
  • How can I fix them?

It is very easy to make an anonymous block, which is why they are so common.  Below are the steps:

  1. Find some geometry that you think should be a block instead of a bunch of line segments
  2. Select and copy all of them with the right click and ‘Clipboard’ copy command or ‘CTRL-C’.  Note: A slight step-up would be to ‘Copy with Basepoint’ (CTRL-SHIFT-C).
  3. Then Right-click and Paste as block.

AutoCAD Anonymous Blocks Video






And that is how they get created!

Now you see how they came to be. As far as why this is a problem, think back to above and how hard it is to identify them to insert another one.  Of course you could copy and rotate the block each time you wanted another copy – which apparently some people do, verses inserting it and allowing the insert routine to offer scaling, rotating, etc… This is shoddy work in my opinion and does not do much for future drawing tasks. Hell, if you are going to do this, at least rename it to something that makes sense – which brings us to how to fix the ones we have.

Fixing Anonymous blocks:


Renaming the anonymous block is the quickest way to fix this issue – this will provide you with a logical reference to the block.  If you have not renamed a block before, you should know that the RENAME command allows you to rename a lot of things in AutoCAD  – look at this list:

Rename Anonymous Blocks











If you want to be able to use the anonymous block in future drawings (Great idea!), you can WBLOCK the anonymous block out to a folder on your server or location where you keep your master blocks.  WBlocking the anonymous block out will still require you know what the block name is, so I would recommend that you rename it first anyway.

WBlocking is easy – lets walk through the steps:

  1. Figure out what the anonymous name of the block is. You can do this by highlighting the block and right clicking to see its ‘Properties’ OR use the ‘LIST’ command.  LIST will allow you to copy the text from the command window and paste it into the next step, which saves some memory brain cells – cool!
  2. Rename the block with the RENAME command
  3. WBLOCK out the block to your standard block library directory
  4. Pat yourself on the back for a job well done!  Now everyone that has access to that directory now can use the block in their drawings!

AutoCAD Anonymous Blocks Video






All fixed!

If you want to know more about creating blocks, creating powerful Dynamic blocks, editing or enhancing the blocks you have check out these other posts:

So what’s next?  What would you be interested in learning more about?  Got an idea for a post? Email me and I’ll see what I can do.


AutoCAD BAD CAD Blocks Hell!


Create real blocks in lieu of Anonymous blocks!









As a designer I work in AutoCAD on a daily basis and use files provided by others.  I am constantly miffed by the level of quality or lack there of in the files that I receive.  Today was another example of what I typically refer to as BAD CAD and why I had to do a little Rant!  But this one got me irked enough to write about it.  Today’s BAD CAD involved an issue I see pretty often, which involves blocks – but this drawing managed to actually cover a few of my hot buttons in one single session.

  1. Blocks were all anonymous “A$C63F21903”, “A$C6F944C45”, etc.
  2. If a block was mirrored, it had another anonymous name
  3. Blocks were created on an ‘ep-text’ or ‘rcp-text’ layer
  4. The blocks were composed of line segments
  5. Blocks were bylayer – Gold Star!
  6. Insertion points were in ‘outer space’
  7. Text was the “Standard” style

For some, the flaws are obvious, for others – maybe not so much.  Let’s look at each one to see what could have been done better.

  1. Blocks are not that hard to make. I understand that you can just select everything and right click to use the clipboard copy option, and then “pastes as block”.  But what you get is a bunch of blocks with no rhyme or reason to their names – anonymous blocks.  This is shoddy work in my opinion and does to do much for future drawing tasks.  Hell if you are going to do this, at least rename it to something that makes sense.  I’ll get more in to the past as block pandemic in future post. [See this post on how to make blocks]
  2. I guess this user did not know how to use the mirror command.
  3. Now these were electrical devices, so I assume the ‘ep’ meant ‘electrical power’ and the ‘ec’ meant ‘electrical crap’ because I couldn think of another good ‘c’ word that made sense since most of the items on the ‘ec-text’ layer were lights.  BUT – how did ‘text’ become part of either layer name – none of it was text! [As an additional note, there were things all over the drawing that had NOTHING to do with electrical that were on the ‘ec-text’ layer!]
  4. This is something that only some die-hard CADD folks might see as an issue. If you make a shape – make it with ‘polylines’ not ‘lines’. I do this to avoid line segment issues should someone (God forbid) exploded it!  it also makes it easier to manipulate when I use ‘Bedit’.  [See post on the Block Editor ‘Bedit’ here]
  5. When I edited the blocks, the line work was ‘BYLAYER’, which is great – gold Star! Of course they lost the star by making the blocks on a ‘ec’-text’ layer instead of layer ‘0’….
  6. When inserting a block, it is great to know where the insertion point will be, like on a wall, intersection of a grid, etc.  But these blocks had the insertion points at random locations.  this typically happens when someone just picks a point in space or creates a block from existing entities and chooses a reference point that relates to that particular location. [See this post on why this is important]
  7. I am all about “Standards” – except using the default AutoCAD Standard styles for anything.

You can check out the 101 series I did earlier on the topic of blocks here.


AutoCAD 2016 Favorite Features

With the release of AutoCAD 2017 out, which I am sure will have some pretty sweet new options and enhancements, I thought I’d reflect on my AutoCAD 2016 favorite features.
Like all users, it is not likely that every new feature or enhancement that comes out will be used.  One of the best strengths of AutoCAD is that it offers a variety of ways to be productive and is flexible enough to be used in any industry.  Like the rest of you, although there are so many new features, I have a few favorites.  Below are the top three features I have enjoyed the most – note that these all work in the LT version.


The XREF properties override variable will help many that deal with external references from providers that practice “Bad CAD” and change entity colors rather than use the color Bylayer option.  With this feature, less work is required on the end user to clean up the external files for their own use.  It can also quickly point out when objects have their color set to by “Entity” instead of the proper “Bylayer”.   How?  Look at the following two examples with the XREFOVERRIDE variable set ON (1) and OFF (0).
Image of a screen capture example when the XREFOVERRIDE is set to zero (0)


When the variable is set to OFF (0), the entities manually set to a color show up that color, and no matter what you do in your Layer  dialogue, you are stuck with that color.  You will have to go in to the actual XREF drawing and change the items to color by layer.

Image of a screen capture example when the XREFOVERRIDE is set to one (1)


When the variable is set to ON (1), the entities manually set to a color will show up as if they were properly set to color “Bylayer” and you will not have to go in to the actual XREF drawing and change the items to color by layer.  This is nice, because with this setting turned on, you can control the colors in your drawing through the layer dialogue and do not have to touch the XREF.  This goes for line types and layer visibility as well.


NOTE: Be sure to have your VISRETAIN variable set to “1” also.

Although the cleanup of external references can be done pretty quickly with a script, the ability to quickly attach a drawing and override the color to “Bylayer” without having to modify the base xreference is very nice.

REVCLOUD Enhancements:

There are a few items in the revision cloud area that have been enhanced and although I have created some scripts to enhance our revision handling process, the new enhancements are a nice addition.
REVCLOUD “Modify”:

Type or choose REVCLOUD command and then select “Modify” (M) option to add sections and remove (cleanup) sections of an existing revision cloud.  Note: Where you pick on the existing revision cloud is where the modification starts.  When you are all done, it is one cloud!

New System Variables:


 Defaults to a specific cloud creation methodology:
     0     = Freehand
     1     = Rectangular
     2     = Closed Polyline


 Controls the number of grips displayed on a revision cloud:
ON     = Endpoint and center grips for each segment (very clean, even on a freehand cloud)
Image of a screen capture example when REVCLOUDGRIPS is set to ON


OFF    = Grips for every arc endpoint and diameter (very messy)
Image of a screen capture example when REVCLOUDGRIPS is set to OFF



How many times have you opened a drawing and while your working, find out that variables have been changed or are set differently than you require or prefer?  The SYSVARMONITOR now gives you the opportunity to know it right away. This is by far my favorite addition to 2016, it’s just a simple GUI tool that anyone can setup with their favorite variables and the must haves for company standards.  As I deal a lot with other people’s drawings, I use this daily.  Once I turned my coworkers on to this, it made everyone’s daily work much better.
System Variable Monitor - AutoCAD 2016 Favorite Features

System Variable Monitor

You could create a Script or even a LISP to monitor and set these settings (which I have done in the past), but for those that want a simple solution – BAM! this is it.

What about you?!

 What are your favorites? In the comments below, let us know what you have benefited from the most in 2016.  If you have made the move to 2017 already, are there some new things you are happy to see?


Basic AutoCAD 101 Rules

Image for Basic AutoCAD 101 Rules showing Standards

Do you have Standards?

Ok – this one is a Rant…

Daily I deal with AutoCAD drawings from drafting ‘professionals’ that seem to still not understand some Basic AutoCAD 101 Rules – (fundamentals).  If you are an architect or architectural draftsperson – think of your electronic drawing audience – i.e. your consultants. Your drawings need to be easy to use for everyone, not just you. Following some basics adds very little time to your work and in many situations will actually save you time.

A few basics..

Color = Bylayer
Linetype = Bylayer

Use Paperspace:

Draw to scale and use Annotative Scaling



Do NOT use the out of the box “STANDARD” styles for Text, Dimensions, Multi-leaders etc… If you love them, copy and rename to something original.

Use Xreference files – NOT blocks when assembling plan drawings.
– i.e. Do NOT create a floor plan and then start a new drawing for a ceiling plan and block in the Floor Plan. With proper Xref management, you can put all this in one drawing.

Do NOT put drawing components in Paperspace – Draw in Model space and create viewports in Paperspace.


Use attributed blocks for Tags, Plan and detail titles – NOT Dtext in circles and squares and lines for underlines, etc…

When doing text, use justification – there are more options than TopLeft.

Use blocks for drawing plan items. If you are going through the trouble to draw something that you plan on copying or even ever using again – in ANY future, make it a block. Dont’ worry about it being perfect – you can tweak it as you learn more or choose to add more detail. You can even save it into a master library. Examples:

For downlights – draw your circle on layer “0” and save as a block called “Downlight” – 5 seconds! Copy this around your drawing and if you want it to look different or change size, just tpe BEDIT and change the block.

Other plan items: All kinds of ceiling or wall mounted light fixtures, furniture, plants, doors, windows, plumbing fixtures, appliances, etc…

Elevation items: Windows, Doors, Light fixtures, signage, plants, etc…


Be descriptive and use more rather than less.

– If you are drawing walls for New, Demo and Future – create them on different layers, NOT on one and change the linetype.
– For a ceiling plan, do not put all lights, diffusers, speakers and sprinklers on the same layer as your grid. Place them on differnt layers – different consultants use them diferently.

Do NOT use Layer “0” for drawing anything but blocks.

Do NOT use Defpoints to draw items you do not want to plot. Make a seperate Non-Plot layer.


Once you draw a plan and send it out – do NOT move it from it’s original location!

Do these basics and the world will be a better place – atleast for me… If you don’t know how – ask me.

Here are some links to some previous posts that may help:

101 Series on the what, why, and how of Blocks

External References – Basics

External References – Details and Commands

Dear Mr./Mrs Architect – another request for assistance


Autodesk University 2015 for First Timers


In corresponding this weekend with a AU first timer, I thought it might be a good idea to share some additional information for other first timers.


When you register at AU you will get a bag (at least that has been the case in the past) which may include a pen and some sponsors literature, but that’s about it. You will also get your badge that will allow you to move around the event and get in to classes.  The badge may also come with some ribbons – like the AUGI ribbon for AUGI members.

Speaking of registering, it is best to do it as soon as possible – Monday, if you can.  By registering early you can hit the ground running on Tuesday. There will be 9000+ plus people roaming the halls and you want any registration formalities out of the way as quickly as possible so you can get to your classes and any events without delay.


I would definitely bring something to take notes with – electronic or paper.   If you have a tablet (like an iPad) or a laptop, that would be best.  Before you leave, go to the AU site and download all your class materials. There will be wireless at the event, but it can get pretty overloaded.

If you are not bringing an electronic device and are going the paper route print your material out so you can follow along.  Bring something to write with (and a backup) as well as a notepad and some highlighters as well to emphasize important items to you.

If you have smart phone, there is an AU app that you can install that will have information on the daily events and maps, etc… Search for it on Google Play Store (for Android) or the Apple App Store – it will be called “AU 2015. Note that if you are traveling from overseas, you may want to investigate a mobile data and minutes package through your carrier.  There is wireless at the event that should handle your data needs, but roaming can get pretty pricey for texting and calling home.

Make sure your luggage is big enough to bring back all the literature and any souvenirs you will get – like the annual AUGI beer glass that you will get a ticket for at AUGI’s Annual General Meeting.

The weather this week in Vegas is forecast to be between 34 and 62 degrees Fahrenheit, so bring some warm clothes if you plan on going out on the strip and do some site seeing.

More Info:

If you have additional questions, you may want to check out this link for AU FAQS.

Autodesk University 2015 FAQs

The exhibit hall opens Tuesday at 6:00pm, and you will want to come by the AUGI booth. We are booth #1369 – you can locate us on the AU Exhibit Hall map.  When you come by, ask for me.

If you have friends or co-workers who are not able to make it, have them at least check out the AU online learning resources at:


I’ll follow up with some news after the event, until then – Safe Travels.


Autodesk University 2015

au-2015The holiday season is quickly approaching, and if you have spent any time in a mall or big box store you will see that the adds for Christmas are everywhere – in some cases they were up before Halloween. It’s hard to think Christmas when just yesterday I was resealing my deck while it was 89 degrees out.

I have a feeling the next couple weeks will be similar, which makes the upcoming trip to the annual Autodesk University event in Vegas a welcome break from the Florida weather.

For those of you that make the trek each year, I am sure you have already booked your flights and selected your classes and are anxiously awaiting the event’s beginning. I know that some of you have still not registered and some may not even know what AU is all about.

For those that are new, let me tell you a little about it. Every year Autodesk puts on a huge event in Las Vegas for the past present and future users of Autodesk products. There are tons of classes, exhibits, demonstrations and parties to keep you busy. Attendees can learn not only about Autodesk products, but even more from vendors and sponsors that are also at the event. Additionally, this is a great place to learn about current and future industry trends and what some of your peers are doing. It is a great event to learn, share, and network.

To get more information and get registered, head over to the AU 2015 website http://au.autodesk.com/las-vegas/overview and get signed up.

If you cannot make it this year, at least check out the AU online learning resources at:


I’ll follow up with some news after the event, until then – Happy Holidays! ; )


AutoCAD 101 Series – External References Week 2 – Details & Commands

xref-0This is the 15th article in my AutoCAD 101 series – to read about the origination for this series, see the first post here: <Intro>  The last post in this series was a summary of external references basics. <link>.   In this post I will discuss various methods of attaching and accessing external references (XREFS) and common commands and system variables.  In the next post I will go over some XREF-ing tips and tricks.
Because AutoCAD now has so many external attachment options, the “XREF” or EXTERNALREFERENCES” dialogue gives you a full picture of all your attachments.  If you choose the drop down menu in the upper left (Figure A), you will see the variety of file types that can be attached to your working drawing.
Figure A – External file attachment options
For daily use, I use the CLASSICXREF command which is “XR” in my shortcut keys to do daily DWG reference functions, see Figure B.
 Figure B – CLASSICXREF Dialogue
 XREF Binding
 Sometimes you may want to make the externally attached files a permanent part of your working drawing, such as for archiving or sharing with another program that does not understand reference files.  Note that Images, DWFs, and PDFs cannot be bound.
 There are two options for binding external references, ‘Bind’ and ‘Insert’. When choosing the Bind/Bind option all logical named items in the external reference files get bound with a prefix denoting the original XREF name. These items include layers, line types, text styles, blocks, dimension styles, etc.… This can make for a very messy listing of the various types or very useful depending on your goals.  Bind/Insert merges all the items previously mentioned into the working drawing. I typically prefer this binding option as it reduces the clutter in the drawing and makes it easy to do updates.
 Below are some screenshots showing the difference between the Bind/Bind and the Bind/Insert options:
Figure C – Layers before Binding
Figure D – Layers after Bind/Bind
Figure E – Layers after Bind/Insert
As you can see above in Figure E, it is much cleaner to use the Bind/Insert option.  Note that the additional “$0$” symbology will also get added to all your line types, text styles, blocks, etc… when you use the Bind/Bind option.
NOTE: If you are having trouble getting files to bind, run an audit and purge on the XREFS and the working drawing, that typically does the trick.
Overlays vs Attachments
AutoCAD has the ability to ‘nest’ XREFs, i.e. attach an XREF that has an XREF attached to it. In the XREF manager (CLASSICXREF) and in the External References dialogue, you will see two icons representing two different dialogue views. You can see when a XREF is nested using the ‘Tree View’.
 Figure F – List View
Figure G – Tree View
The benefit of this feature is that you can stack XREFs for coordination purposes.  I.E. Assume you are working on a reflected ceiling plan and you need to coordinate diffuser and sprinkler locations with your lights, you can attach the HVAC plan and the sprinkler plan to your file to do your coordination.  You can keep these files attached for future change coordination but hide them from view.  In the “Xref Manager” dialogue, select the file you wish to hide and choose the Unload button.  In the “External References” dialogue, right click the file and select ‘Unload’.  These functions are all part of the normal nesting function of XREF attachments.
There is another attachment option called “Overlay” that allows you to attach a XREF to a file and only allow it to be seen in the current file.  Note that this does not work for Images, DWFs or PDFs.  Using the above example for coordination, if the Electrical designer wishes to power up the lights, they could attach the reflected ceiling plan to their lighting plan to do their circuiting.  If the HVAC plan and the sprinkler plan were standard XREFs, they would see that on their plan as well.  If they have no need for that, to avoid possible confusion you could attach the HVAC and sprinkler plans as “Overlays” and the electrical designer would not even know that they existed.
 You can change the reference type on the fly;  In the “Xref Manager” dialogue, select the file you wish to hide and double-click on the word ‘Attach’ or ‘Overlay’ under Type and it will change. In the “External References dialogue, right click the file and select Attach, and in the pop-up make your change.
Figure H – Xref Manager
Figure I – External References
 Commonly used external Reference Commands
There are a lot of commands and system variables that can be used when using External References, but like most other AutoCAD features you typically only need a few.  Below are the most common commands and SETVARS that you would use on a daily basis.
Edit Reference In-Place
Allows clipping (hiding portions) of the XREF from view. Great for enlarged plans or partial details.(NOTE: for other file types: PDFCLIP, DGNCLIP, IMAGECLIP, DWFCLIP)
Allows binding of individual items from an external DWG file attachment. Say you want to bring in ablock or linetype from the external reference, use XBIND to bind it and then rename it if you would like.
Commonly used external Reference SETVARS
Controls visibility, color, linetype, lineweight, and plot styles. Should be set to “1”.
Controls the dimming for all DWG XREF objects. (Fade from 0 – 90%, user visual preference)
Controls the notification for updated or missing XREFs. Should be set to “1” or “2”.
Controls the default reference type when attaching or overlaying an external reference.  This depends on use, but the majority of XREFs will be “Attachments”, not “Overlays”.  See “Overlays vs Attachments” section above.
 If you are currently using external references then you have already seen the many advantages that they provide.  If you are not currently using external references, it’s about time to get attached!     In the next post I will go over some XREF-ing tips and tricks.
If you run into a snag with any of the topics her or have additional questions, email me at walt@functionsense.com

AutoCAD 101 Series – External References Week 1 – Basics

xref-0Are you new to AutoCAD? Have you been using AutoCAD for years but only use the blocks, styles, layers and tools that others have created?  Do you want to learn more or step up your game on features you’re not very strong in and pick up some practical examples of best practices?  If so, this series is for you.

Over the course of 12 months and maybe more I will cover the basics of a lot of AutoCAD tools and features that many may want or need to learn more about. This is the 14th article in my AutoCAD 101 series – to read about the origination for this series, see the first post here: <Intro>The last post in this series was a wrap-up of all the Block Posts. <link>.

So now we move on to another tool – “External References”.   If you are not using External References (XREFS), which has been around for a long time, you are really missing out on a powerful tool.  If you are a current user keep reading, maybe you will find some new things covered here that you may have been a bit curious about.
Throughout the XREFs posts I will refer to the process of attaching external reference files as “XREF/XREFING”, to the attached files as “XREFS”, and to the drawing that you attach XREFs to as the working drawing.
What are External Reference files (XREFS)?
External references are much like the concept of blocks which was the old school way of handling many of the functions now provided by external references.  Rather than being embedded (inserted) in the file they are externally ‘attached’ or ‘referenced’.  Items that can be attached include; DWGs, PDFs, DGNs, DWFs, and IMAGES (BMP, JPG, TIFF, PNG).  Different commands can be used to attach the various external files, and these commands start with the file type and the word “ATTACH”; PDFATTACH, DGNATTACH, IMAGEATTACH, DWFATTACH.  Or, you can just use the XREF command which will allow you to attach any type from one dialogue.  The individual commands are great for use in automation efforts (Macros, Scripts and Lisp), but will not likely be your first go to option.
Why do you XREF?
Because it is the right thing to do of course! If you are new to AutoCAD and XREFs and wonder what all the fuss is about, XREFs provide a lot of pretty cool features.

  • They keep your working file size small
  • They allow sharing of files while providing real-time updates
  • They are great for coordination
What do you XREF?
As stated above in what are External References, you see a lot of file types that can be attached to your working drawings. Typical items you that would attach include floor plans, title blocks, logos, standard details, survey pictures, and product literature.  But, if you have any of the file types above that you commonly share in projects the options are unlimited. See ‘Figure A’ for the various file types that can be attached in AutoCAD 2015.By choosing the drop down menu in the upper left, next to the DWG with the paperclip, you will see the variety of file types that can be attached to your working drawing.  Because AutoCAD now has so many external attachment options, the “XREF” OR EXTERNALREFERENCES” dialogue gives you a full picture of all your attachments.
Figure A
Why Block Insert when you can XREF?
The big difference between working on a background that is a block verses a background that is an XREF is that the external XREF can be worked on by someone else and be shared real time with multiple users or files.  External references keep your drawing files small and allow you to share the background with multiple drawings.
Example Uses
The following are examples of how XREFs can be used to increase your productivity. The one big advantage that every one of these examples is that when you update the XREF every file that references it is updated.
Title Blocks
This is probably one of the top two uses of external references. In a typical project the one item that is common among all drawings is the title block.  By XREFing the title block drawing you can make changes to the address, issue date, customer info, and logo in one place and have all of your working drawings updated automatically.
Note that the logo in the title block is another common XREF (IMAGEATTACH). You can also enter all your revision info for the entire job in this drawing as individual layers. I. E. REV-1, REV-2, etc… freeze them in the title block and thaw as necessary in the working drawings.
Floor plans
Probably the top use of XREFs.  Through a combination of external references, clipping, and paper space, you can attach multiple plans and plot at different scales all on one sheet.
XREF’s can be renamed when attached, and by doing this you can attach the same file multiple times and control the visual aspects of each as if it were a separate file.  This is referred to as logical name versus the actual name. An example would be attaching a floor plan (FP-1) that has demo and new work layers all in one drawing.  By attaching FP-1 and then renaming it in the XREF dialogue to FP-Demo you can freeze and thaw layers as required to show the demo portion of the plan. You then attach (not copy) the FP-1 plan again and freeze and thaw layers as required to show new work.  Since each logical XREF has its own layer structure showing up in your layer dialog you can also change colors and line types.
Note that this feature relies on your VISRETAIN SETVAR being set to “1 “.
Product literature
In some jurisdictions it is required manufacturers data, safety information, or product performance, is shown on the drawings. Instead of retyping all this data or redrawing it (or creating sticky backs for you old-timers) just XREF the PDF or image files into your working drawings.
Standard details
Nearly every set of drawings utilizes some form of standard details. You could have a standard detail sheet with the details XREFed so that the sheet is always up-to-date.  If you need to revise a standard detail to be job specific or freeze the details specifics from changing during the course of the job, you can bind those details into your working drawing and edit as required with in the current job.
Survey information
When doing renovation projects, a necessary task is to provide enough information on the existing conditions to allow contractors to be able to see what they face so they can give an accurate bid.  Although requiring a field visit is always a good idea that is not always practical for some projects.  A great way to enhance your drawings is to IMAGEATTACH field photos in your drawings and add notes detailing the specifics.
Key plans
When working on large building projects or campus wide projects, you can attach aerial views or screenshots from your favorite mapping program to visually show your site or campus.  For the large building projects you can attach a drawing at a reduced scale of the overall building with hatched areas or layers frozen or thawed to represent specific areas of work.  Any plan changes will automatically update your key plan as the project progresses.
These are just some of the uses for external references.  Your imagination can open up many more.
In the upcoming posts I will cover commands and settings that are important and useful for utilizing XREFs efficiently.
If you run into a snag with any of the topics her or have additional questions, email me at walt@functionsense.com