How to Calculate Floor Area Ratio [FAR] for your building project as per RAJUK rules

Updated: Jun 17, 2021





When someone decides to build a building in Dhaka City [RAJUK area], Two obvious questions will come into mind first.

  1. What will be each floor area?

  2. How many floors can be built?



So How can you get a fast and accurate answer to these questions?

Easy! Check the neighboring buildings of a similar type of plot. Did you get the answer? Oh.No You did not! Why? Because there are so many variations for the same size or type of land. So it's quite confusing. Isn't it?


Then, what to do now? There is only one correct way to figure out the right answer to these questions. Dhaka Imarat Nirman Bidhimala 2008.


As per Dhaka Imarat Nirman Bidhimala 2008. First, you have to calculate the total build area or construction area. Then divide the build area into floor numbers. That's it.


So Let's start to calculate the build area as per Dhaka Imarat Nirman Bidhimala 2008. We will try to keep this procedure as simple as possible. Now,


  • Built area = FAR x Land Area



01. To calculate the build area you have to know the following basic information about your land.

  1. Land Area

  2. Access road width

Basically, these two pieces of information will determine the FAR ( Floor Area Ratio ) number for your land.



A. Land Area and Land Access Road Width:

  1. In general, without exception, The width of any access road to a plot must be a minimum of 20 feet or 6 meters. So if your plot access road width is less than 20 feet, You have to surrender 50% amount of the land area out of the total required land area to make the road width 20 feet. See the following fig to get an idea.

  2. If there are multiple roads around the plot, this fig is independently true for all the roads.

  3. Surrendering land area for road widening or having a road width of more than 20 feet has some benefit. You will get some extra built areas for your building.

  4. Your new land area will be the plot area after deducting the surrendered land area.


[ Extra Information: how to be confirmed that whether you have to surrender any part of your land or not or how much land has to be surrendered? The answer is when you will apply for LUC ( Land-use clearance ), RAJUK will determine and declare this information in your LUC paper. ]


B. Determine FAR [Floor Area Ratio] number for your land


You can determine FAR for your land from the following table. This table is taken from Dhaka Imarat Nirman Bidhimala 2008. [Fig: 51 Table 3 (ka), Page 3035 from the Dhaka Imarat Nirman Bidhimala 2008.]


Before determining the FAR number, keep in mind that to acquire a specific FAR number you have to match both land area and land access road width from this table. In case it doesn't then the lower value of these two factors will determine the FAR number.


Let's see an example, Say You have a land of 15 Katha area and the width of the access road to the plot is 6-meter or 20 feet. As you can see in the following table, the FAR number is mentioned on the 12 No slab for 15 Katha land. But the FAR number for your land will be from 9 No slab because the last FAR number for the 6-meter road is mentioned on the 12 No slab). So access road width of the plot plays a vital role to determine the FAR number.

[ see the following table fig 51 to find the slab FAR number ]


Sometimes some additional bonus FAR can be acquired if you have surrendered land area for road widening or already have a wide road more than 6 meters or 20 feet. But this bonus FAR can't be more than the next slab of your basic FAR number of the land.


Say you have a land of 5 Katha and the width of the access road to the plot is a 9-meter. As you can see from the following table that the FAR number for 5 Katha land is 3.50 and the FAR number for the 9-meter road is 4.50. Since you can only take the FAR number from the lower value, the FAR number for your land will be 3.50. This is the basic FAR number for your plot. but you are eligible to get some bouns FAR since having a road width of more than 6 meters or 20 feet. We have skipped the calculation considering its complexity. But keep in mind that the Total FAR = ( Basic FAR + Bonus FAR ) can't be more than the next FAR number of this table. So as per this example, the total FAR number can't be more than 3.75 (slab 05).

Fig: 51 Table 3 (ka), Page 3035 from the Dhaka Imarat Nirman Bidhimala 2008.


02. Build Area Calculation


Now you know

  1. Your land area

  2. The FAR number for your land


Build Area = your land area x FAR number

That's it. you successfully completed the mission!



Here Build Area means FAR included construction area.


What is included here?

1. Usable Floor Area

2. Lift-lobby and stair Area

3. Any common space


What is Excluded here?

1. Ground Floor Parking Area

2. Rooftop area

3. Front Verandah area

4. other Verandah area


03. Now you have the answers to your earlier Questions.


  1. What will be each floor area?

Answer: Build area divided by floor number


2. How many floors can be built?


Answer: Build area divided by floor area.


Please note that the floor area can't be more than Maximum Gound Coverage [MGC]. Each specific FAR number has a specific MGC. You can find out the MGC from the above-mentioned FAR table. [Fig: 51 Table 3 (ka), Page 3035 from the Dhaka Imarat Nirman Bidhimala 2008.]


Unless more than 150-meter tall building RAJUK usually doesn't decide the building height limit. It is determined by the client's choice. Sometimes, It is also determined by other agencies like Civil aviation, Fire department, Traffic, etc. in spacial cases.