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Back To Work, Part 6: Continuing Our Discussion Of Design And Engineering

Continuing our discussion of design and engineering.

This is Part 6 of a series.

Welcome to the next installment of my series on getting back to work. The goal is to offer reminders on, tips for and thoughts about each of the seven stages of a project. I hope to make this a worthwhile read by bringing something to the fore that you either didn’t know or long ago forgot. So far, we have covered pre-sales, preliminary design and documentation, and the kick-off meeting. This month, we will be continuing our discussion of design and engineering. To get fully up to speed, I recommend that you read last month’s article. It had a couple of good tips, as well as a sidebar on defining the word “success”.

By this stage, you should have a good feel for all the changes on the project, as you’ve been communicating with your team members to double check all the details (e.g., color, quantity, shipping delays, model changes, discontinued items). By this point, you should be feeling pretty confident that you can proceed. It’s time to start drawing!

The First Step

The first step for me centers on infrastructure and device count and location (unless this was already done due to the construction schedule). You must convert all the marked-up plans into drawings. The first step for me is to make a list of all the floor/wall/ceiling boxes. From that list, you have to determine what symbols you are going to use and the appropriate nomenclature.

For example, a floor box might be a square with “FB” inside; a wall box might be a square with an upside down “T” and “WB” inside. Then, you have to determine how you’ll distinguish one from the other. I happen to use subscript capital letters in a corner. There might be three different floor boxes; therefore, if you were using my method, you’d have an “A,” a “B” and a “C” type floor box.

Now, you have to go to your cover sheet and, under your “Symbols” header, insert the symbol that you’re using for each of these types of floor boxes. Then, you have to provide a description of the floor box, including make, model and other particulars. This, of course, also goes for all the other symbols you plan on putting on your floor plans and reflected ceiling plans (RCPs).

Insert Manufacturer Details

If this is a bid project, I now go to the device-details pages that I already created and, for any devices other than a traditional floor, wall or ceiling box, I start inserting manufacturer details that I already have into each of the viewports. I make sure that every atypical device gets a detail. If I’m missing any information, I reserve the spot by putting large-print text in the viewport to remind me that I need details for “XXX” device.

In case you don’t remember, or if you didn’t read last month’s article, I have two different drawing sets. One has all the background plans on it, all the external references (XRefs), etc. The other has the cover page, details, single line drawings, rack elevations, etc. I don’t like to have active XRefs in my drawing while I’m working on other types of drawings in the set.

Shifting back to the plans, the next step is to locate all the symbols (devices) on the drawings. This is done in model space in AutoCAD on an overall plan that you likely have XRefed in. Now this is important: I use two of the same. The first one is, and always remains, blank in model space. This is where I show the complete, overall space on a drawing, using thick, dashed boxes and a detail bubble to highlight which areas will have devices (shown in paper space). It also includes the drawing number and detail of the partial plans or enlarged plans.

Avoiding Device-Count Errors

The second one is where I locate all the devices that will show through the viewports on the partial plans. You do not want to show devices on both plans, as doing so can lead to ordering and device-count errors. (Note: Some companies, depending on the size of the space, do not use partial plans and just work off one plan view. If that works for you and they can be seen, great! It means less work. For me, however, with most projects having many spaces on a building floor, it’s just too small.)

Here’s another tip: When inserting the devices, I number every one (unless it is unique). For example, let’s say that I have three FSR FL-500P floor boxes, and I denote them as “Type A.” Next to my “A” subscript, I put a “1,” a “2” and a “3.” So, each symbol representing this floor box is now unique—namely, A1, A2 and A3. I do that because there might be many of the same devices in a room. Who wants to be talking to someone and have him or her say, “The Type A floor box…the third from the left.” It’s much easier to call out floor box A3. This, of course, goes for all the devices and it’s my standard practice, I highly recommend it!

I now add my verbiage to the “General Notes” placeholder that I already inserted. Be careful here, as you likely have similar verbiage from other projects. Make sure that you scrub the document to remove words that are clearly not referencing this project! Avoid the now-famous cut-and-paste errors that we’ve all made. These notes are in paper space—not model space—and I like mine on the top right of the drawing.


Now, we turn to the pièce de résistance: The all-important (and my personal favorite) keynotes! I like infrastructure plans to be exceptionally uncluttered—just symbols and a keynote directing you to what you need to know about the device. Here is a sample from a courthouse that I did:

Portable lectern AV, voice, data, power floor box type “C.” Provide FSR model FL-500P-6 with trap door carpet insert cover. 4-gang section is for AV; 2-gang section is for voice, data; and 1-gang section is for power. EC is to provide three 1.25″ conduits for 4-gang section and terminate in AV equipment room #226 accessible ceiling in labeled “AV conduit” area. See Detail 1/AV-100 and Detail 5/AV-312 for additional information. Coordinate exact location with general contractor, architect and/or owner.

Design-Build Project

If you paid attention, you noticed that there are no cabling details in that keynote. The reason is that it was for a bid project. The winning bidder would then create shop drawings, including revised keynotes that would call out cabling details, and submit them to the consultant. If you were working on a design-build project, you’d of course have to include the cabling details in the keynote, as well. Sample verbiage for cabling information for a hotel project I worked on is as follows:

Wall box type “C.” Electrical contractor is to provide and install one 3-inch-deep, single-gang wall box. Locate as shown and mount at standard switch height. Verify actual location with general contractor and/or architect. Stub up one 0.75-inch conduit to accessible ceiling. AV contractor to provide and install two West Penn 25225 plenum cables for wallmount screen control. Home run cables to AV equipment rack area, located in storage room #216 as shown by clouded area. See Drawing AV-201, Detail #2; Drawing AV-300, Detail #3; and Drawing AV-402, Detail #1 for additional information. Leave 20 feet of cable bundled at equipment rack area and label accordingly.

Keeping Things Simple

To keep things simple, on the top line of my keynote, I include the phrase “This Sheet Only” in smaller text. What I mean by that is that keynotes are unique to the drawing itself—not unique to the drawing set. With the alternative method, you’d have to juggle all your keynotes from drawing to drawing, and, many times, there will not be repeats. On that point, to each his or her own. Happy infrastructure drawing!

Next month, I will continue to go into detail about how I do my design-and-engineering drawings. Don’t forget that I would love to get some feedback on this series. Share your thoughts about your definition of success, given that I broached the subject last month. Or just share your views on the design-and-engineering process.

To all, stay safe! Let me know if you have any questions, comments or stories you would like to share. Please email me at

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