May 5, 2023

How to Determine Buildable Area

Before designing a structure, developers and civil engineers need to know how much land is actually available to build on. But how does one accomplish that if there is no one way to compute development yield? 

Thanks to 25+ years of experience, our team of land planners, designers, and surveyors know exactly what to do. We’re giving you a walkthrough of how the JBPro team approaches calculating site capacity and feasibility. 

Start With Site Planning

The best place to start a site analysis is understanding where a piece of property fits into the surrounding community and what site permits will be required. Some questions we ask include:

If any of these questions yield answers that are not aligned with the project intent, you will likely have to proceed with a land use change or rezoning application. These processes are approved by the governmental body or bodies with jurisdiction over your property. While not uncommon, these proceedings can drastically lengthen the timeline of a project and still may not yield the desired developable area due to objections brought up during the process.

However, if your project intent aligns with the jurisdiction’s and your site permits are approved, design discussions can begin to determine what your resulting site plan will look like.

Common Development Site Yield Detractors

We have already addressed a few of the preliminary standards that may prohibit development. Now, we can move on to the required elements that must be accounted for in the design of every construction project.

Infrastructure Requirements

Most regulated elements are directly tied to the infrastructure of a site. Infrastructure can refer to any facilities or systems that serve the surrounding area.

  1. Stormwater Facilities – Preparing for rainfall and any resulting runoff is a crucial component of a successful project, both during and after the completion of construction. If your property is located in an urban setting, some stormwater management elements may already be accounted for. If they are not, retention ponds and other drainage infrastructure can take a significant portion of square footage from your site. 
  2. Parking – The one thing everyone needs and there is never enough of – parking. Most government institutions have specific calculations for the exact number of parking spaces required based on elements like building capacity, square feet, and usage. Allowances must also be made for access aisles, loading zones, and ADA Standards for accessible parking. 
  3. Open Space Requirements – Required open space is an allotment of unobstructed area that must be specifically made available for the use of people in the area. These areas usually include parks, plazas, or green spaces, but stormwater basins can occasionally be considered open spaces based on project details. It’s important to have an experienced team to ensure these requirements are met to avoid incurring any additional costs or delays.

Natural Features

One of the most beautiful elements of developments to consider are the existing natural features of a site. 

As civil engineers in north and central Florida, we are often faced with the challenge of building on or around wetlands. To be designated as a wetland, the Florida Department of Environmental Protection requires two of three conditions to be present: hydrophytic vegetation, hydrology, or hydric soils. 

Example of wetlands that could be difficult to build on

Wetlands can present challenging conditions to build on, beginning with getting a permit to do so. As a result, wetland areas are often left untouched and do not contribute to the total buildable area. 

Other, more obvious aquatic factors are features such as lakes or rivers which cannot be mitigated or built upon. If those areas are prone to flooding, an experienced engineer can give you an estimate of the site design elements that might be required to prevent future flood damage. 

Trees can also account for a significant portion of necessary building adjustments. The JBPro blog has already gone into great detail of how a tree can affect land development, but the important takeaway is that a site’s building area may face either legal or budgetary arboreal constraints. 

Offsite Impacts

Not all restrictions are directly attributable to the property in question— offsite conditions may contribute as well. 

Consider a roadway – it needs entrances, exits, drainage, bike lanes, and many other factors to operate at an optimal capacity. Oftentimes, developers are required to account for these access requirements in their own construction plans. 

These transportation systems play a huge role in a community and require a large amount of planning to function effectively. The most important thing to consider with transportation infrastructure is the capacity of surrounding roadways. With developments of significant impact, there may be roadway upsizing, turn lane additions, or new traffic signals needed to fulfill permitting requirements.

Lastly, utility requirements can dictate the need for additional coordination with local agencies and neighboring property owners. Oftentimes, developers need to get easements from nearby landowners to get utilities to their site. These utility easements could include water, sewer, electrical, or telecommunication infrastructure. Thankfully, utility requirements can be evaluated during due diligence long before you make a real estate investment.

Pre-Acquisition Due Diligence With JBPro

If all of these factors leave you with less space to build than you expected, don’t be discouraged. Your vision can still be brought to life because maximizing buildable area does not always create the best design – experience does.

Equip yourself with the best consultants to guide you through the development process. JBPro elevates projects with excellent site planning, stormwater modeling proficiency, and innovative designs. If you want the best team for your next project, let’s work together.