How to urban plan with TestFit

Urban planning is crucial for real estate developers and cities alike to understand how a site will be developed and monetized over the next 10+ years. 

As an architect, how do you solve for multiple sites? How do you cope with design changes and iterations? How do you make sure you’re meeting density goals & parking requirements? If you’re anything like I was in my previous life as a Project Designer at an architecture firm, it involves a lot of hand-sketching and a helluva lot of rework.  

Here at TestFit, architects often come to us looking to solve 4-6 parcel sites that work from both a physical and financial point of view with real-time takeoffs. In this article, we’re going to cover exactly how to tackle this problem.

Figure 1.0: Live tabulations of the site

The 78

We’re going to go to a favorite site of my colleague’s in Chicago that has been slated for redevelopment for many years. The site is a massive park on the river near the United Center stadium.

Figure 2.0: Our proposed site in the South Loop of Chicago

A few important caveats before we get started:

  • This plan was done in 30 minutes; it is by no means a perfect urban plan. However, it does show you how quickly a detailed layout can be created with takeoffs, net rentable, parking ratios, and more with instant design iteration. TestFit’s Manual Mode allows you to further tweak those design details towards a truly perfect master plan. 
  • To keep it simple we’re going to ignore the train for now. 
  • Some people prefer working from inside of the site, outward; for this how-to, we’ll be working from the outside of the site, in, starting with site context! 

Let’s dive in 🤿.

1. Context, context, context

When we look at the surrounding area, we can see some major retail north of the site. So we’ll provide commercial connection along that edge. Using our institutional knowledge, we’ll use offices as anchor tenants for this space as we know they are heavily in demand in this region in Chicago.

Figure 3.0: Building context

There’s also a transit hub nearby, so we’ll build in some high-density housing with one of the mixed-use buildings at the top.

Figure 4.0: Measurement tool

Let’s also plan for a few approved developments planned nearby that we’ll need to consider.

Figure 5.0: Proposed buildings in massing mode

2. Wide open spaaacesssss

Whether it’s going to be on this urban plan or an adjacent site, open spaces are at the top of the list when planning public spaces. In order to preserve Chicago’s long history of public green space near waterways such as the park spaces along Lake Michigan, we’re going to make sure we offset our roadways from the river.

Figure 6.0: Existing waterway

You can also use the roads editor (which we’ll get to below) to add more green spaces by simply changing your presets.

3. Roads

All great urban plans typically start with a framework aka roads. As you know, framework gets you really thinking about how all the sites are connected and how you’re going to grow it. What’s great about TestFit is we can update that framework instantly. This process traditionally is very cumbersome with many revisions required, especially if you have to go back to redo the roads once you’ve started to work on your density. 

We’re going to use TestFit’s roads tool to start from larger, boundary roads, and move in. As you can see below, we’re outlining the site with larger avenues and smaller streets.  , Using the “Sections” menu on the left-hand side, simply select the type of road you want, and draw it in the viewer window. Intersections are automatically created. Simple in TestFit. Not so simple by hand.

Figure 7.0: Creating the site with boundary roads

Next, we’re going to program the site with a few retail anchor tenants accessed by secondary roads as you can see below.

Figure 8.0: Creating secondary roads with TestFit’s street tool

TestFit’s “Roads Editor” allows you to create custom streets sections and other accessories like on-street parking.  Bike lanes allow tenants to enjoy the outdoors, the great river, and the close car-free transit options. Parking is of course always a biggie and we’ll get to that in our individual sites shortly.

Figure 9.0: Adding on street parking, sidewalks, & bike lanes

Pst: If your client / traffic engineer / civil engineer / the city has critical feedback after traffic analysis, roads are simple to change WITHOUT killing your buildings. The buildings will simply adjust, maintaining your desired inputs. Setback and buffer adjustments are similarly adjustable.. Ask us about a demo today to see it for yourself.

We’re placing a few final roads using our lanes and alleys in the “Roads” tool and our sites are now defined:

Figure 10.0: Adding lanes and alleys with TestFit’s Roads tool

For more information on roads, including curved roads and more, check out our Knowledge Base article.

4. Building Time 😎

We’re going to pop some buildings onto each of the sites and then play with building typologies to get as close as possible to our feasibility study. All sites auto-populate with a 5-story wrap but can be changed to any topology desired.

Figure 11.0: Preliminary building inputs on our chosen sites

Site A

As previously mentioned, we planned for commercial space for the top half of the site. For Site A, we’ll start with office space using the “Site Type Selector”. Office space near the urban core of Chicago has historically been a solid move, but with unforeseen circumstances like COVID variants, we need an easy way to cycle through typologies or compare different schemes.  . Luckily, that’s exactly the kind of flexibility TestFit provides.

Figure 12.0: Generating an office building using the core-based buildings site type

We’re going to increase the height of our office building and check out some of the tabulations available. 

Fig 13.0: Takeoffs available from our full-height office building

For more information on TestFit outputs, check out our Knowledge Base article.

Site B

Moving on to  Site B, we’re going to provide a mixed-use tower with retail, office, and multifamily residential. As we really just want a sense of space here, we’re going to play with TestFit’s massing mode (select “Mass-Based Buildings” from the “Site Type dropdown”). Voids, setbacks, program by level, etc, can all be adjusted in real-time. In the end, we settled on multi-level car parking on the first couple of levels, retail on the next level, office levels, then multifamily at the top. We decided on retail above grade as the roadways are actually elevated around it. Check out our real-time decision-making based on some of our research and institutional knowledge around the site.

Figure 14.0: Conceptualizing a mixed-use tower featuring parking, retail, office & multifamily

We’re going to build up this building, using more voids and offsets to create an amenity deck, as shown below.

Figure 15.0: Amenity deck and setbacks added to multifamily portion of tower

Under “Building Input”, we’ve set the efficiency to 80% for our multifamily section of this tower, with a 780’ unit average for Chicago’s hot market. We’re going to adjust our parking requirements to 1 stall per unit as the building is close to public transport. You can see from the red text at the bottom right-hand corner that this scheme still does not meet the parking requirements for this site. We’ll need to continue working with the inputs to find a valid output. TestFit’s real-time feedback makes this quick and easy.

Figure 16.0: Playing with TestFit inputs in mass-based buildings

For more information on mass-based buildings, please check out our Knowledge Base article.

Site C

For Site C, we’re going to switch to the podium preset, increase the height of the initial building, and change our unit average. We’re going to aim for a unit mix of 50% studios, 30% one-beds, and 20% two-beds. This is all real-time math, with a visual understanding of what the layouts will look like. We’ll also add some setbacks to let some natural light in. We’ll do that by holding the shift key while dragging the edge of the building.

Figure 17.0: Changing multifamily unit height & averages, and adding setbacks

Density can be more manipulated here by adjusting the courtyard aspect ratio, adding verticals, etc. The lifts need a bit more work here, but for now, it’s enough for just allocating space.

Figure 18.0: Changing the input’s in TestFit’s high-density configurator

For more on high-density inputs, check out the Knowledge Base article

Pst – enjoying the article so far? Subscribe to make sure you don’t miss the latest blogs & news. The article continues below!

Site D

On Site D, we’re going to place a podium hotel. TestFit auto-generates 4 possible options at the bottom-right of the screen and we will toggle to Option A.

Figure 19.0: Deciding on schemes for our hotel building

We’ll substitute the standard units to hotel standard which is a pre-made database in TestFit. We’ll drop parking down to 0.5. We can see in real-time how many keys we are getting in the tabulation underneath to know if we are roughly hitting our desired count.

Figure 20.0: Adding standard hotel units

For more information about TestFit for hotels, please check out this info page.

Site F

On Site F, we’re going to match some of the existing density opposite this site with some lower-density deals. After adjusting setbacks, we’ll start to play with the lower-density housing site types.

Figure 21.0: Turning site E into low-density housing

Next, we will alter our townhouse inputs, including row maximums and minimums, row gap sizes, side-green and back-to-back buffers.

Figure 22.0: Altering low-density inputs in TestFit to achieve a roughly ideal Townhouse layout

Instead of hopping right into manual mode, we looked at our unit sizes and decided to use parameters to adjust the density (in this case unit depth).

We can also enable entries by clicking “Site Exits / Show” and dragging and dropping them into position. We’ll also add a park right opposite the entrance as a common transitional space. We’ll use our “Spaces Tool” to create the park, change the space type to park, and change the color.

Figure 23.0: Modifying the community entrances and adding a communal park

Site E

We’re not too sure what to do with this one. Garden apartments or more single-family housing are viable possibilities. We’re going to start with garden apartments on this site.

Figure 24.0: Laying out garden apartments

We’re not quite getting the density we want and the parking is a little off from our goals. So we’re going to save this scheme to revisit later, save the parameters as a preset from site F, and apply that preset to the low density on site E as a new scheme. The last step is to match the unit sizes in the “Configurator Panel”.

Figure 25.0: Saving sites E and F as scheme

After mirroring the layout of Site F, we can compare metrics between the schemes. Surprisingly, while garden apartments seem the least dense, they’re actually denser, with 120 units.

Figure 26.0: Comparing density between the two schemes

5. Zooming out again

As we toggle into 3D context at the bottom of the screen, we can see that our plan of echoing the existing neighborhood and moving from high density to low (from top to bottom) is panning out pretty well.

Figure 27.0: Populating 3D context on our site

At this early design stage, we can apply budgets to quick takeoffs from TestFit to make sure we are in scope. Based on this, we can pretty easily draw some informal conclusions on whether the site will work or not. 

We can show our real estate developer client these findings to make sure we are on the right track before diving into more critical elements of the buildings (i.e. life safety, amenities, back-of-house rooms, parking details, etc, and the details that truly define a space like unit layouts and balconies). 

It is crucial to note that this is just a first iteration: The ultimate power of TestFit lies in the ability to instantly iterate on your designs in real-time as many times as needed.  

Here’s a demonstration of how you can change your roads without completely losing your hard work on the buildings

Figure 28.0: Move roads around and watch buildings change

My kind of fun


When people think of TestFit, they usually think of it for single sites. But as you can see, urban planners, real estate developers, and architects alike can use it for much much more. I like to think of it as tech-enabled sketches that sparks data-driven creativity. 


Move the conversation from a napkin sketch to data-driven solutions in a matter of minutes. 

Not yet using TestFit? Sign up for a free trial.

5 TestFit & Revit workflows to maximize your design process via Dynamo

TestFit to Revit using Dynamo

You want to be able to create powerful geometry and data in TestFit, but also be able to pass that information into Revit and AutoCAD for more detailed design and documentation. We’ve already created a process to export to AutoCAD and we’re happy to share we’ve created some new, more robust workflows to get your data and buildings from TestFit to Revit and vice versa.


At the moment, we believe that Dynamo is the best way for TestFit users to pass data back and forth. Although there are easier ways to do this (we’re looking at creating a Revit Add-in in the future), Dynamo allows you to customize the geometry and data you want to manipulate in Revit. We’re breaking down the 5 scripts below or you can skip ahead to download the scripts.

1. TestFit Building to Revit

Let’s say you’ve created a fantastic building in TestFit and TestFit has created all the data you need to know to turn this deal into a building. No one wants to rebuild or redraw a building they have in one software into another. With this script you can choose the Revit families you want to describe your walls, floors, roofs, etc. and create the building from the TestFit .RSD file. 

Figure 1.0 : Easily assign family types to TestFit geometry to create your building in Revit.

2. Revit to TestFit Kit of Parts (KOP)


Your firm has a library of typical apartment units you pull from for every project. To make it easy, we’ve created this workflow to allow you to bring those units and their descriptions into TestFit as a Kit of Parts (KOP). Select the walls and input the unit type and it will save it as a .KOP file so it can always be accessed in the TestFit unit editor. 

Fig 2.0 - Convert typical Revit units into a Kit of Parts in TestFit.

3. Revit Interior Fitout with TestFit Building and Revit Typical Units

After bringing your building into Revit you can fit out the interior of the apartment units with this script. By creating model groups of the typical apartments, this script will take those units, associate them to the unit types in TestFit and place them accordingly into the Revit building. From there, if you’d like to make an edit to any of the unit types, all you have to do is edit the main model group and your changes will occur in the rest of the units.

Figure 3.0 The Dynamo script places and rotates all typical unit model groups within your building in Revit.
Fig 4.0 - Enlarged view showing apartment units fit out with model groups in Revit.

4. TestFit Property Line to Revit Model Lines

Just select the .RSD file that contains a property line in TestFit and this script will bring the geometry into Revit as model lines.

Property lines from TestFit to Revit
Figure 5.0: Transfer property lines from TestFit to Revit.

5. Revit Model Lines to TestFit Property Line

This script allows you to do the opposite; bring Revit model lines into TestFit as property lines. Simply select the model lines in Revit and location of the .RSD file to save it.

Figure 6.0: Transfer Revit model lines to TestFit Property Lines.

Dynamo Setup

Step 1: Download the TestFit Dynamo scripts package by filling out this form:

Step 2: Download the amazing packages that our scripts are powered by. To do this open Dynamo, go to Packages>Search Packages, and download them there:

a. Clockwork

b. Archilab

c. Spring nodes

d. JsonData

e. Data-Shapes

f. TestFit Dynamo

Please note: These scripts are based on Dynamo 2.6 however should work with any Dynamo version above 2.0. They have not been tested against versions lower than Dynamo 2.0.

Dynamo Player

Most of the TestFit Dynamo scripts can be run directly out of Dynamo Player. Just point your Dynamo Player Directory to the location you placed the scripts and press the play button for the script you want to run. If you want to see what is happening in the background, you can click on the pencil icon next to the play button.

Pro tip: placing the script folder on a network drive is a great way for more employees to be able to easily access them and make sure all of you are working off the same version of them.

Figure 7.0 Dynamo Player

Our user interfaces are powered by the Data-Shapes package, which allows us to make simple user interfaces for you to work with. This prevents what we call “Spaghetti Shock”, the feeling when you open a large and complicated Dynamo or Grasshopper script and feel utterly worthless. When you press play in Dynamo Player, one of these UIs should pop up. Input the necessary parameters and run the script!

Dynamo Spaghetti Shock
Figure 8.0 Sample Data-Shapes package user interface.

Example TestFit Dynamo script

We’ll use the TestFit Building to Revit script as an example. If you’ve followed the above steps correctly, your Dynamo Player should look like the images above. Click the play button for the TestFit Building to Revit Script and a UI will appear. The dropdown box titles will vary depending on the families in your Revit project. 

Select the filepath of the TestFit .RSD file you want to bring into Revit and select the family types you would like for each TestFit geometry. Click import and you are done! Depending on the complexity of the building, it could take somewhere between 10 seconds and 5 minutes. You should be able to see progress bars in the bottom left of the Revit window.

Make Revit go brr

With these scripts we hope that we empower you to better utilize the geometry and data you create in TestFit in other stages of the design process. If you have any feedback on the scripts, suggestions on other ways to improve TestFit, or just want to send us a funny gif, don’t hesitate to send it to Nat.

Special thanks again to the great Dynamo packages we used to power these workflows:

Crash Course in Test Fitting

Table of Contents

Its About Solving the Deals


In this blog post I will attempt to give readers a crash-course in test fitting. We will use our software, TestFit (fitting name, no?) to show many of the concepts, along with some meaningful graphics to explain deal concepts. If you already know why we test fit, you can skip ahead to the TestFit crash course.

One side note: The audience for this post is students interested in using TestFit for coursework or real estate development competitions. Experienced architects and developers might not learn too much, other than the basics of our software.

Why do we do test fits? The answer lies in how complicated it is to create viable real estate deals. Real estate deals, in the mind of this author, boil down to five sub-problems:

  1. Design – How is the product designed?
  2. Capital – How is the deal structured? 
  3. Land – Where is the building, and shape of the land it is on?
  4. Construction – How will it be built, and what will it cost?
  5. Zoning – Does the design conform, or will it need additional entitlements?

Capital, Construction, and Zoning

Capital, construction, and zoning generally start out on a pretty solid set of facts: LPs and GPs want to achieve a solid YoC (normally 6.5%), GCs simply execute on construction documentation while meticulously keeping track of cost. Zoning is generally known, and operates under various land use controls like DU/AC, FAR, Height, and Lot (or building) coverage.

Some Definitions:

  • LPs: Limited Partners, often the equity component of a real estate deal
  • GPs: General Partners, who are normally referred to as “Developers” in the USA. 
  • GCs: General Contractors, the companies that get buildings constructed
  • YoC: The ratio of money made in the first 12 months to total cap ex
  • Cap Ex: Capital Expenditure, the money spent by companies on physical assets
  • FAR or Floor Area Ratio: the ratio of built floor area to the land it sits on (see image below)
  • Lot Coverage: the percentage of the lot covered by building
  • DU/AC: Dwelling units per acre
  • Acre: 43,560 square feet, or 1 Chain*1 Furlong (the area an ox team can plow in one go)
FAR: Floor Area Ratio - what is the total building area compared


Land is a pretty simple concept. It and its fixtures are static, unmoving, and permanent. The only asset class that is said to be “real” hence the term “real estate”. Land gets a bit complicated with assemblages, but in general its analysis is limited to who owns it now, what kind of soils are on it, what kind of zoning is attached to it, what kind of private covenants are associated with it (hello Houston), and how bad is its topography.

Some Definitions:

  • Assemblage: Putting together several parcels to make a new, more valuable parcel (see below)
  • Private Covenant: Zoning, but without government intervention (Some private covenants can and have been ruled unconstitutional, however)
  • Fixture: Anything attached to the land. If you have to hire someone to move or demolish it, its a fixture.
  • Topography: The slope of a site, and how extreme that slope is

Solving the Subjective Design Component

Now into the meat and potatoes of what we are best at here at TestFit Inc: Solving the spatial layout. The main problem with building design is that there are no “right” answers. The solution space is as large as the universe itself. At TestFit we simplify buildings down to component parts to constrain the solution space from infinity to only a few trillion possible solutions.

The Major Components of the Design of a Housing Deal

Depending upon the land, zoning, capital and construction, the makeup of the following list will change drastically on a percentage basis.
  • Dwelling units – housing for people and family
  • Parking facility – housing for cars (we build a lot of this in the US)
  • Human circulation – corridors, stairs, and lifts for getting to units
  • Car circulation – roads for moving cars around
  • Leasing and amenities – space to convince people to rent

The table below gives some comps between building types and their respective component percentages. In a world where a YoC of 6.5% is desired, increasing the area of units versus all other spaces becomes quite important. This is actually an industry metric: Building Efficiency. Building efficiency is most often used without the parking facility.

320 Units @ 875 SF Avg
Space TypeWrap DealPodium DealGarden Deal
Parking Facility30.7%29.6%29.2%
Stairs + Lifts1.6%1.8%0.9%
Leasing + Amenity1.0%1.0%1.1%

Some Definitions:

  • Wrap Deal: Parking facility is wrapped with housing units.
  • Podium Deal: The housing units sit atop the parking facility.
  • Garden Deal: The housing is individual buildings, surface parked.
  • Building Efficiency: The percentage of the building that is rentable.
Building Efficiency what is the total area compared to the usable or rentable area?

Using TestFit to Solve Deal Design

Now we transition to the more practical part of this blog post: how to use our software to solve deal design. TestFit supports some construction, capital, and zoning problems, but only at the highest level. It’s main focus is using algorithms to allocate net rentable area on a plan, and to create a vision for what a project could  be.
The following series of videos give an overview of how TestFit works. 

Working With Presets

The building types mentioned above are easily wielded within TestFit’s configurator by using our default presets. This ~9 minute video will give a good overview of those presets and building types. 

Working With Sites

Within TestFit we use sites to define the land area. Sites also have some other interesting properties, like setbacks. The following video will give an overview of sites.

Understand Density with Sites, Schemes, and Presets

The cross product of the last two videos is how sites (land) and (building design) presets work together to show what density is possible with different combinations of the two.

Using the Zoning and Building Inputs

Now that you have a handle on sites and presets, let’s take a look at zoning parameters and how to get into the weeds via building inputs.

These few tutorials are just the beginning on how to solve or even optimize real estate deals using TestFit. If you would like to learn more via tutorials, please check out our Knowledge Base. Not yet using TestFit? Sign up to try it now.

Concluding Remarks

I hope this post was informative on why we design different shapes and styles of buildings. With tools like TestFit, anyone can now site plan buildings. It is a democratization tool. That being said, it takes several years to fully understand the true nature of buildings, and for users to get an intuitive sense of how they should solve a deal–but it takes decades without technology to have that same sense.