One aspect of property development that’s often overlooked is calculating the floor space ratio. What property developers don’t realise is that it’s a more straightforward process than they think.

Floor space ratio (FSR) is a concept that every property developer should know. But the reality is that many property developers overlook its importance.

But what is it exactly?

Simply put, FSR measures the maximum allowable floor area in relation to land size. It’s used to determine the size and form of your property development.

Since development standards vary per council, it’s best you’re aware of the FSR limits in your area. After all, local governments set their own urban planning and zoning regulations.

Calculating the FSR may seem complicated. But the reality is that it’s a straightforward process involving just four steps. Here are the steps to do it:

The 4 Steps to Calculating Your Property’s FSR

Step #1. Determine the total floor area

The first step in calculating FSR is to determine the total floor area of the proposed development. It must cover all floors, including basements, mezzanine levels, and rooftop spaces.

Let’s consider a hypothetical residential development with three floors, each measuring 200 square meters. In this example, the total floor area would be:

Total Floor Area = 3 floors * 200 sqm/floor = 600 square meters

Step #2. Measure the land area

Now that you know the total floor area, you then need to measure the land area on which the development will be constructed. 

Continuing with the example above, let’s assume that the property’s land area is 500 square meters.


Step #3. Divide the total floor area by the land area

Divide the total floor area obtained in Step 1 by the land area determined in Step 2. This will give us the FSR value.

The formula looks like this:

FSR = Total Floor Area / Land Area

Plotting the numbers, the equation will be:

FSR = 600 sqm / 500 sqm = 1.2

So, the FSR value for this example is 1.2. This means the total floor area of the structure is 1.2 times the size of the land area.

Step #4. Interpret the FSR

As mentioned, different cities and regions may have specific FSR limits based on local zoning and urban planning guidelines. To ensure compliance, the FSR value you obtained in Step 3 must be compared to the allowable FSR for your property’s location.

Now, let’s assume that the local planning regulation in the area of our example allows an FSR of up to 1.5.

In this case, the calculated FSR of 1.2 is below the allowable limit of 1.5. This means that the proposed development project complies with the FSR regulations. So, the property developer can proceed with the project.

However, if the calculated FSR were higher than the allowable limit—say 1.8—the developer would be in breach of the FSR regulations. They would then need to adjust the design, reduce the floor area, or seek approval for a variation to the FSR limit before proceeding.

Keep in mind that everything needs to be in balance. The final FSR you settle on should be based on city regulations, your resources, and the current state of the market.

Additionally, local councils may update zoning regulations periodically. That’s why it’s your responsibility as the property developer to check with your local planning authorities for updates. 

Always consult with professionals to ensure compliance.

The 3 Options For Calculating FSR

Option #1. Do it yourself

While this can save you money, it can be time-consuming and prone to errors. You’ll also need to learn how to properly conduct a survey and buy expensive equipment.

Option #2. Hire a professional

A surveyor can easily measure and calculate your FSR for you. This option is easier, but you can incur significant costs. 

Option #3. Use Archistar

Archistar has an advanced prosumer feature that lets property developers effortlessly calculate FSR for their property. By streamlining the process and providing up-to-date zoning data, Archistar eliminates the gruelling task of FSR calculations. 

With Archistar, you can save time and money and ensure accurate results. This makes it the best option for savvy property developers seeking efficiency and precision in their property development ventures.

Do More Efficient FSR Calculations With Archistar

Calculating FSR is a vital step for every property developer, particularly in ensuring compliance with local regulations and avoiding costly mistakes. 

While there are various methods to calculate FSR, they can be time-consuming or expensive. They can also provide you with inaccurate results, which can cause problems down the line.

The easiest, fastest, and most cost-effective solution lies with Archistar. Combining its up-to-date zoning data with its mathematical efficiency means it will provide you with accurate results for your FSR calculations.

See how Archistar can make your FSR calculations a breeze by trying it out for free today.