Spaces instead of Areas

Area plans have their quirks. They can only exist in their own special area plan views. They've got rules and quite often people want to break those rules. If we need to do that then we end up sketching boundaries a lot. Areas don't know anything about Rooms either. That means we're probably going to have to enter some data twice if we must use Areas pretending to be Rooms, all to document fussy Room area requirements

If that's the situation we find ourselves in...do we have access to MEP's Spaces? If so we could consider...this...

The plan in this image is an architectural model (yeah really simple mock-up). Is it obvious what I've done? I've got Room tags reporting area only as well as Space tags reporting a little different area value along with Room name and number. It also has a Color Scheme applied to Room departments.

It's also a separate model I called Area Calcs. I linked the Architecture model into Area Calcs. The Room tags I mentioned a moment ago are actually Room tags, tagging each room's area in the link. For Spaces however I opted to just sketch Space Separators over the linked model since I need to identify different parts of the room's boundaries to calculate area anyway. A Space isn't different from a Room when we rely on walls for their boundary, in how they calculate area at least. Sketching our lines gives us complete control over the results without dealing with Area Rules.

A Space Separator is a linestyle (like Area Boundary and Room Separator) and I changed the appearance to a much thicker burgundy line so it stands out against the linked file's plan. I ended up applying transparency to Walls too. Once I defined the boundaries I needed I used the Space tool and opted for Place Spaces Automatically. This creates a Space wherever one is possible within the boundaries I've created. This is done floor by floor, assuming there is more than one floor.

Just in case you weren't aware of this already, a linked file has a Room Bounding option.

If this option is selected then Place Spaces Automatically creates Spaces wherever Revit finds Rooms and valid boundaries even where there aren't any rooms (note my interior design comment later). Since I need to define room area differently that's not going to help me now. It's intended to speed up the process for engineers while they are preparing their project to start work.

Now that I've got Spaces I can take advantage of a separate tool called Space Naming Utility (SNU). It is crazy that this tool is still a separate installation but it is. At least it isn't locked away in subscription only access anymore. I keep hoping it will show up inside Revit in the next release.

Sorry I digress, it (SNU) will read (from the linked file) each room's name and number and pass it to the equivalent Space's name and number.

One risk here is Revit might not figure out which Room is supposed to be related to a Space. However, if we examine the properties of a Space we'll see right away whether Revit can see a room relationship or not. Plus any Spaces that don't update will be a clue or at least identify a Room that hasn't been filled out with information properly yet. I'm hoping to apply the 80/20 rule here and win.

If I want to use Fill Patterns too, like below, I can create a separate view that only shows a customized Color Scheme that applies Fill Patterns instead of a solid color fill. Then I just stack (overlay) this view on top of the other floor plan on a sheet. I just need to make sure the view is using Wireframe so it doesn't mask the floor plan.

I can even add a separate Color Scheme legend to the other view that's stacked over the floor plan.

Choosing this route might come down to how I answer these questions:

• Do I have Spaces? (Are they part of the Revit version I use?)
• Which is worse, sketching Space Separators or Area Boundaries?
• Which is more fun, using Space Naming Utility or manually updating Area data to match relevant Room data?
• If I know a Dynamo/API programmer then maybe I can improve the Room to Area process instead?

This popped into my head last evening while I was mulling over a client's email. I've suggested using Spaces in the past to help deal with linked interior design models so this time around it didn't seem quite as crazy to me as it did the first time.

Want to poke around the files (Revit 2015) I used for this post?

Area Plans
Area Calcs

Your mileage may vary...

New Area Schemes

Revit provides two default Area Schemes in the stock (Imperial) templates;Gross Building (can't be deleted) and Rentable. When we want to create an Area Plan view Revit expects us to choose a scheme. The additional scheme in the following image is one I created (Retail Zones).

What isn't obvious, without a little digging, is that we can create more schemes. This is important because it does no good to attempt to reuse an existing scheme for additional plan views. They remain biased toward displaying whatever boundaries we've created already. Creating more area schemes begins here Architecture ribbon tab > Room & Area panel drop down > Area and Volume Computations > Area Schemes Tab.

Once you've made it here you can create new or delete existing area schemes. As mentioned earlier Revit's locked down the Gross Building scheme.

Now you can return to creating a new Area Plan view and choose from among the new schemes you've created. If you intend to use a Color Fill Legend you also need to make sure you create a new legend type for your new area scheme.

A Little Quick Area

If I need to find the area within some sort of boundary the first expectation among AutoCAD users is "Where is the Measure tool in Revit?" There is a Measure tool but it measures distance between a couple points or a chain of points. It doesn't deal with Area.

For that we can use a Region, either Masking or Filled. I sketched a Masking Region using an arbitrary boundary within a plan that isn't already clearly defined as a separate room or space that could easily provide an area to me. I'm imagining a quick draw response to my boss looking over my shoulder and asking, "How much area is there between this, this, that and that?" Start region, sketch with the Chain Option on, Finish Sketch - "There is 375.46 SF sir."

I can just delete the region once I've found the answer. If I create the region in a working view (one that isn't getting printed on a sheet) I can just leave it there for awhile so when the boss comes back and says, "How much area was that again?" I've still got it and only need to look at its Area parameter. A floor could do the same thing, same number of clicks and it also knows perimeter and volume.

No it isn't a tool called Measure Area but the task and click count is at worst an extra click, maybe two compared with the Measure Area in AutoCAD. A keyboard shortcut and it's no more effort at all. It's the same only different.

Edit/added: I mentioned in a comment that the reason Area exists/is a parameter for regions is in response to users requesting the Measure Area tool in AutoCAD.

Room Area Net vs Gross

When it comes to documenting room area we have one global setting called Room Area Computation, found in the Area and Volume Calculations dialog.

We get to choose from four options that affect the entire project's room area calculations: Wall Finish, Wall Center, Wall core Layer and Wall Core Center. Wall Finish tends to work for net area calculations while Wall Center works better for gross area.

When we need to be able to show both net and gross one approach we can take is to use Area elements and Area plans. Unfortunately area and room objects are totally ignorant of one another. That means an area plan using area elements is NOT a room so we've got a lot of redundant data entry to deal with. Another way to deal with it is to print sheets with the Room Area Computation set for one condition and then switch to the other setting for other sheets intended for that condition. We'll need some "redundant" views with tags etc. but perhaps it will provide the necessary differences required.

Another possibility if we are using Revit, the version that includes all the disciplines tools, is to take advantage of MEP Spaces. They ignore the Room Area Computation setting, they only reference Wall Finish. This means I can create a space for each room, yes some redundancy. I can use the Space Naming Utility (subscription extension) to pass the name and number of the related room to the space name and number parameters so I don't have to enter the redundant information. The end result could look something like this, where I use a plan focused on spaces and another focused on rooms to show both net and gross area calculations.

This nexst image is Gross Area using Wall Centerline as the Room Area Computation settings.

This image is the Net Area using Spaces instead, leaving the Room Area Computation the same as for the above.

This is using Area elements instead matching names and numbers manually. The API might be able to be harness to resolve this to some degree.

Something to consider.

Tagging Elements and their Area

Revit allows us to tag rooms and spaces to display their area. If I'm tempted to do the same for Walls, Floors, Ceilings or Roofs the list of available system parameters (built into Revit) does not offer Area. Revit MEP users can tag a Duct's area.

It seems to me a bit arbitrary to disallow the tagging of data that is part of the element. We can see it in the element properties and include it in schedules. While a schedule is an ideal way to summarize data a floor plan is useful to provide context AND display a variety of information, like area.

It would be excellent to see more parameters unshackled.

Area - What's the Difference?

Two methods exist in Revit to document area; Rooms and Areas. Okay technically this is true for Revit Architecture (RAC). Revit MEP has Spaces and Zones too but this post is focused on RAC.

A room and its area is defined globally, affecting all room areas, by one of four methods.

All room areas are determined by the existence of walls or room separation lines. The following image has  some rooms, note the "X" in each room. These are a room's reference sub-category, usually turned off in Visibility/Graphic Overrides, and the center of the "X" is the origin of the room.

Areas are a broader, a bit more involved, but more flexible way to define area inside or outside a building. Areas are documented using special plan views according to a specific area scheme.

Consider a shopping mall, think of Area as an individual store or tenant and rooms as the storeroom, bathroom, fitting rooms etc. as defined by the partitions within a tenant's leased space. If that relationship makes sense you have a sense of the application of rooms and areas. Another way to think of them is of a college building with a dozen classrooms for mathematics. Each classroom is a unique area while an Area can be defined to include all of the classrooms as a single area designated as Mathematics. I apologize for the overlapping terminology, we use "area" interchangeably for a number of things which makes it a bit like, "Who's on First?".

The above image shows the mathematics area but I also added another area for parking. This shows that WE can define what the boundaries are for each area as required.

Rooms are fast and easy but universal, calculated by the same boundary location. Areas are defined by boundaries that you choose to define yourself. Areas combined with Area Schemes allow us to provide summaries using different assumptions, like gross area versus rentable (stock settings in Revit). Area boundaries can follow walls or be based on boundary lines that we sketch ourselves regardless of building elements. The Area tools are the most similar to sketching polylines in AutoCAD that many of us are familiar with except that we can schedule the resulting data very easily and have it update dynamically. More work to be sure but much more flexible too.

Something to keep in mind is Areas and Rooms are not aware of each other. An Area cannot tell us how many Rooms exist within its boundaries. This has always felt like an oversight to me. My feeling was amplified when the Revit MEP product introduced Spaces and Zones and Zones are aware of Spaces. They have the sort of relationship I've always felt Rooms and Areas should have. This means you can define tenants with Areas and create Rooms inside their space but an Area schedule can't summarize the rooms it has inside. Two schedules will have to tell the story instead of one.

Area Measurement - An Arbitrary Tool

A common request is for a tool to quickly measure the area of something. It's created a number of angry or puzzled posts at AUGI over the years. Most describe the tool as, "Give us the same tool as AutoCAD's Measure tool".

In my view most of the reasons for such a tool are disguised suggestions for improvements to schedules. A few examples? Glazing reports for the exterior envelope of a building. The Area tools would cover this but they don't work in elevation because of their bias for plan views. Some others are the area of Louver, grills, diffusers and floor materials or patterns. It comes down to curiosity I suppose, "How much area does this thing cover?".

I've no objection to having a quick area tool but we ought to be defining the kind of data that we'd like to have quick access to anyway, that Revit SHOULD do or provide. If we need the area of louvers once, chances are good we'll need to check those numbers again. Computers are good at that, why should we have to sketch around louvers at all or worse create a spreadsheet for that information? A louver schedule ought to provide a quicker summary of all of them. A quick look at the properties of a louver ought to tell us that.

A measure area tool would still be good to do something arbitrary once in awhile.

Incidentally the Region tool will do exactly that with maybe an extra click or two. They added that to the tool as a result of this issue. It is something you can keep for awhile too, or throw away. Seems that most people object to extra step of deleting the resulting Filled Region. We have to cancel out of the command in AutoCAD don't we? Semantics really. It'll get you what you want for now. If you set up an extra view to create them in you can revisit them anytime you want.

We can remind them that we'd still like a specific tool as well.

Percentage of Gross

In a database environment we can create a query that asks questions of data stored in tables or other queries. In this Revit is a little different. We can ask questions (queries) of tables (element categories) all day long but we can't ask questions of the answers to previous questions...or in database terms a query of a query.

There is one example in Revit that is already wired to permit such a result, a percentage of another value, such as Room Area. In this example I've made a little tiny project, created a schedule and added a calculated value to the schedule. This is the final result of the schedule.


This is the properties of the calculated value.



Any parameter's data type, based on what you include in the schedule, and tell Revit to Calculate Totals will be an option for consideration with "Percentage" selected. For example these are my choices if I also include Perimeter and Volume in the schedule.

Dept. of Subtle - Grammar and Warnings

This might be something only an English major could love but it fits nicely into this department. I was alerted to this by Eric Stewart with Design Development Architects. I hope this one doesn't stop you in your tracks when you see it the next time!


I try not to throw stones too much since I tend to butcher my native tongue as well!

Occupancy Calculations

A time consuming task for architects is the evaluation of the project's intended occupancy and its impact on egress from a building. It is possible to improve this process considerably with Revit by reporting data in Room schedules. However simply reporting this same information in a room tag isn't so trivial.

The fundamental problem is that we can not display data that we calculate inside the project in a tag yet. A tag family can not use the area value in an equation because it doesn't exist until you are in a project.

This FILE is an example of a strategy that reduces some of the drudgery of looking up data and having the numbers "crunched" but leaves us with manual data entry to get the information in tags so it can be display meaningfully in plan views as well as listed in a schedule. I did the work in this example but the inspiration goes to WLC Architects, where Scott Davis used to work. It is an imperfect example/solution but should serve as inspiration for your own approach to this issue.

Some of my thoughts about how this might change in Revit:

We need a way to tell Revit that a tag will use a project value, like area, once it is inserted and an object is tagged. A placeholder for AREA that will assume the true value when you tag a space but in the family itself substitutes a temporary value so the formula will "work".

Alternatively we need a system family tag type that can combine instance data like Area with other shared parameters to display calculations.

A third concept might be schedules that actually behave like tags and allow freeform placement of parameters and linework to look like a tag.

Yet another is to allow us to map one parameter to another within a project. Essentially allowing what we have done in these schedules manually to be done automatically, ala Excel...Cell A1 is equal to Cell J4.

In terms of value delivered, this sort of evaluation/calculation is a process that all firms go through to some extent. Evaluating occupied spaces and demonstrating how the design meets the code. This is a business problem Revit needs to help us resolve. Giving us greater ability to decide where and how information will be displayed is very important.

The bottom line is we need a way to display calculated data in tags.