What is Carpet Area, Built up Area and Super Built Up Area?

When you buy, sell or invest in a property, you do a lot of research, as you need to understand all the basic real estate terms. Carpet area, Built-up area, and super built-up area are three such terms that help in determining property pricing, usability and overall value. 
Many buyers don’t pay attention to this when they buy a flat or home, and this leads to a lot of confusion. This mostly happens as many don’t know what is built-up and carpet area. 
In this blog, we will understand more about these three, how they are calculated and how they are different from each other. So read on to find out what is a super built-up area, and how you can find the number by doing some simple math! 

Let’s start! 

What is a Carpet Area?

The carpet area is basically the area of the flat or house where you can lay a carpet. This is only the floor area of the halls, rooms and kitchen; the walls, balconies and utility are not included in it. 

Real-life implications for homebuyers: 

• Since the carpet area is only the part of the home that you can use, it will impact your living conditions. As a homebuyer, get the correct number for the carpet area before you make the decision. 
• Many builders advertise their latest projects based on their super built-up area. Don’t pay heed to this number and ask for the actual livable space of the house. 

For example, a flat advertised to be 1000 sq. ft., may actually have a carpet area of only 700 sq. ft., which means that only 70% of the space is usable. 

How to Calculate Carpet Area?

The formula for carpet area is pretty simple: 
Carpet Area = Total Floor Area – Thickness of the internal walls. 

Let’s take an example calculation:
Say, the total floor area of a master bedroom in a flat = 500 sq. ft. 
And the combined thickness of the internal walls = 50 sq. ft. 

Using the formula, 
Carpet area = 500 – 50 sq. ft. 
So, the carpet area of the bedroom is 450 sq. ft. 

General Carpet Area Calculation

Here are some ways in which the carpet area can be calculated without the formula: 

• Carpet Area as a Percentage of Super Built-Up Area
  • The carpet area in many residential projects is 70 to 75% of the super built-up area. The numbers may vary, often depending on the builder’s construction design and project layout. 

• Influence of project layout:
  • Developers who build bigger common areas like the lobby, clubhouses and corridors have a lower carpet-to-super built-up area ratio, which means that you will get less usable space if you buy that property. 
  • On the other hand, a higher carpet area means the design is more efficient, such as at Raymond Realty’s Address by GS – Bandra, meaning that there will be more space for you to live in. 

• Standardisation Under RERA:
  •  The Real Estate Regulation and Development Act (RERA), has made carpet area calculations more uniform, meaning that there is now more clarity. 
  • Developers are also required by law to tell all new buyers the real carpet area,  allowing you to compare your list of properties according to the usable space. 

Common Mistakes During Measurement:

• Including Balconies or Terraces in Carpet Area:
  • This is a very common error; while measuring the carpet area, many developers count balconies, terraces and verandas as part of the calculation. 
  • So, if the balcony of a house is 100 sq. ft., it will not be added to the 700 sq. ft carpet area, or it will lead to a higher price, which will mislead buyers. 

• Misinterpreting Internal Wall Thickness:
  • The carpet area doesn’t include the thickness of the internal walls; only the space where a carpet can be physically laid. 
  • A room with 10 sq. ft internal wall thickness should consider only the floor space and not the area occupied by the walls. 

• Overlooking Irregular Room Layouts
  • For properties that have irregular room layouts, calculating the carpet area is often tricky. 
  • Buyers or builders may end up counting unusable floor pockets, like narrow corners or sharp angles as part of the carpet area.

• Failing to Verify Measurements:
  • Buyers often depend only on the numbers given by the developer, and don’t bother verifying the actual carpet areas. 
  • By using the formula or by third-party verification, you can identify differences and ensure that the number is accurate. 

Importance of Carpet Area

The carpet area is more important than the super built-up area: 

• Usability: The carpet area directly impacts how much livable space you will get for the money you pay. 
• Transparency under RERA: Since builders have to tell you the real carpet area under RERA, you know you will have correct information, making your buying decision easy.  
• Better Comparison: If the exact carpet area is clear, then you can make a fair comparison between properties based on the usable space. 

Key Insight: Always focus on the carpet area while evaluating the property’s value, as it reflects the space you will be living in. 

What is a Built-Up Area?

The built-up area of a property is the carpet area, plus the thickness of the external and internal walls, and the additional spaces like the balcony, terrace and utility area. 

So, the components of the built-up area include: 

• Internal and External Walls
• Balconies and terraces at the property. 
• Utility areas like wash areas or storerooms. 

The built-up area could be 15 to 25% larger than the carpet area, depending on the walls’ thickness and design layout. 

How to Calculate Built-up Area?

The built-up area is also very easy to find: 
Built-up area = Carpet Area + Wall Thickness + Balconies. 
Let’s take an example calculation: 
If the carpet area is 700 sq. ft., 
Internal and External Walls is 100 sq. ft., and the balcony is 50 sq. ft.,

Using the formula, 
Built-up area = 700 +100 +50
Built-up area = 850 sq. ft. 

However, many times, mistakes are made when calculating for this number: 

• You might often assume that the built-up area and the carpet area are the same, which could lead to more confusion.
• Sometimes, balconies and terraces are included in the carpet area, which can lead to higher numbers and mislead buyers.

Importance of Built-Up Area

Role in Construction Costs: 

The built-up area often influences construction expenses, since it includes walls, balconies and other semi-usable spaces. Many real estate developers determine their properties’ prices based on this number, as it reflects the total coverage for construction. 

Usable v/s Unusable Space: 

• Built-up area often includes spaces like walls, which are not usable for living purposes. 
• As a buyer, always try to understand how much space is usable. Don’t ever pay for a home that charges you unnecessarily for the unusable spaces. 

Always remember to check the carpet-to-built-up area ratio so that you know that the space you are paying for is worth it. 

What is the Difference Between Carpet Area and Built-Up Area?

Differences between the carpet area and the built-up area are: 

Feature	Carpet Area	Built-up Area
Definition	Usable floor space	Carpet area + wall thickness + balcony.
Includes	Bedrooms, living rooms and kitchen	Walls, balconies and utility areas
Excludes	Walls, balconies and terraces	External walls and common areas
Usability	Fully usable	Partly usable
Price Impact	Lower costs	Higher costs due to added spaces.

Real World Implications: 

• Carpet area matters more for living spaces, as it reflects the usable space. 
• Having a good understanding of the built-up area will help you work out a better price for your house. 
• Invest in a property that has a high carpet-to-built-up area ratio, because that will help in maximising the value. 

What is a Super Built-Up Area?

The super built-up area is usually determined by the builder and has the built-up area, with a proportionate share of common areas, like the lobbies, staircase, elevators and amenities, So the developer determines this number and markets their projects based on it. 

The super built-up area includes: 

• Carpet Area
• Built-up area
• Common spaces like lifts, corridors, lobbies and amenities. 

Differences between the super built-up area and carpet area: 

• The carpet area is a usable space in your home.
• The built-up area adds the wall thickness and balconies to this calculation. 
• The super built-up area includes shared and other common spaces, causing the home’s price to increase more. 

How to Calculate Super Built-Up Area

Finding the super built-up area is pretty easy. Here is the formula: 
Super built-up area = Built-up area + Proportionate share of common areas. 
Here is a step-by-step guide on how you can calculate the super built-up area using the formula:

Step 1: Find the built-up area. 

The built-up area of the apartment is the carpet area, walls and balcony spaces. Let’s assume that this particular flat’s built-up area is 1000 sq. ft. 

Step 2: What’s the total common area?

It’s the total area of shared spaces like lobbies, corridors, lifts and clubhouses in the building. Now we assume that this is 10,000 sq. ft shared by 50 flats. 

Step 3: Calculate the Proportionate Common Area. 

So now, every flat gets a share of the common area, based on the total number of apartments. 
Proportionate Common Area = Total Common Area/Total Number of Apartments. 
Substituting the values, we have: 
PCA = 10,000/50
PCA = 200. 

Step 4: Use the formula to find the super built-up area. 

Super built-up area = Built-up area + Proportionate share of common areas. 
= 1000 + 200
= 1200 sq. ft. 

Thus, the super built-up area is 1200 sq. ft. 
This is a very simple way of finding this number, as developers do it differently: 

• The super built-up area is the result of adding the built-up area and the assigned share of common facilities 

• Often, shared amenities, like clubhouses and gyms are added too, and this will increase the number. 

Importance of the Super Built-Up Area

Connection with Amenities and Property Value: 

• Enhanced Amenities: A larger super built-up area often means that there will be more, or premium shared facilities. 
• Pricing Strategy: Many builders price their projects based on the super built-up area. The higher the super built-up area, the higher the pricing. 

As a buyer, make sure you look for these so that you don’t end up paying extra for space you won’t get to use. 

• High Loading Factor: An extremely high loading factor, especially if it goes above 50%, means that the usable carpet area is lesser, compared to the super built-up area. 

• Transparency Issues: Always seek clear information and explanations to find the allotted common areas, as many developers don’t reveal this. 

• Unequal Comparisons: Never compare two properties based only on the super built-up area. This can lead to confusion, especially if one has better carpet area utilisation. 

What is the Loading Factor?

According to RERA, the loading factor is a percentage that denotes how much additional area has been charged to the buyer and covers the non-usable spaces like walls and common areas. 

How is the loading factor used in the real estate sector? 
Builders often apply the loading factor to the carpet area, to calculate the super built-up area. 
A high loading factor will lead to higher costs while offering less usable space. 
In India, the average loading factors vary from city to city. For example: 
Metro Cities: 30 to 50%, as most residential projects have larger shared amenities. 
Smaller Towns or Rural Areas: 20 to 30%, since shared spaces and amenities are limited in these areas. 

How to Calculate the Loading Factor?

The formula for calculating the loading factor is: 

Loading Factor = [Super Built-Up Area – Carpet Area/Carpet Area] x 100. 
Here is an example calculation: 
Say the super built-up area = 1200 sq. ft. 
Carpet area = 800 sq. ft. 
Applying the formula, we get: 
Loading Factor = [Super Built-Up Area – Carpet Area/Carpet Area] x 100. 
LF = [1200 – 800/800] x 100
LF = 50% 
This means that 50% of the carpet area is added as loading to get the super built-up area. 

Why You Should Know About the Loading Factor

The loading factor plays an important role in real estate, helping buyers make informed buying decisions. 

Impact on Usable Space: 

• A high loading factor will reduce the carpet area, while increasing the property prices, often determined based on the super built-up area. 

While buying, you need to negotiate with the developer for the following information: 

• Ask for the loading factor calculations while discussing about the property. 
• Make sure you compare similar projects to identify which one offers better carpet area ratios and negotiate based on those insights. 

Built-Up Area V/S Super Built-Up Area

So, are there any differences between built-up area and super built-up area? Here are four ways how: 

Aspect	Built-up Areas	Super Built-up Areas
Definition	Carpet Area + Walls +Balconies	Built-up area + Proportionate common areas
Includes	Walls, balconies and utility areas	Lobbies, corridors and amenities.
Impact on costs	Direct construction costs	Inflated price per sq. ft.
Usability	Partially usable	Includes shared spaces.

Always review the floor plans to clear up any confusion regarding these differences. 

Difference Between Carpet Area, Built-Up Area and Super Built-Up Area

Key Considerations for Buyers

Here is a checklist you can follow while evaluating the property: 

• Focus on the carpet area when you want to understand the usable space. 
• Request for a breakdown of all area calculations. 
• Ensure compliance with RERA for clarity in measurements. 
• Compare loading factors and common area allocations for similar properties. 

FAQs

1. How does RERA define the carpet area? 
   According to RERA, the carpet area is the ‘net usable floor area,’ inside the apartment, and doesn’t include wall thickness and shared spaces. 

2. Can a developer include amenities in calculations for the built-up area? 
   Yes. However, developers have to reveal the exact proportions and areas that have been included in the calculations. 

3. What is the loading factor in metro cities? 
   Loading factors usually range from between 30 to 50% in metropolitan areas, often influenced by the scale of shared amenities. 

Conclusion

Make sure that you understand the definitions and calculations of carpet, built-up and super built-up areas, to help make informed decisions. Knowing what they mean will empower you, and help you negotiate better, preventing any confusion while assessing the property. 

If you are ever confused about all three definitions and want detailed information about them, then use this guide to clarify property choices and ensure that your investment is given a fair value!