If you want to know about the occupant load calculation or elements of design or fire tower, please click the link.

“FLEXIBLE FAR” in architecture likely refers to “Flexible Floor Area Ratio.” Floor Area Ratio (FAR) is a zoning term used in urban planning to control the density of development by regulating the ratio of a building’s total floor area to the size of the lot on which it is built.

A “Flexible FAR” allows for some variation in the FAR for a given development, typically through bonuses for certain design features, such as incorporating affordable housing or preserving historic structures. This provides more design flexibility for architects and developers while still maintaining overall control over the density of development.

Flexible FAR basically in three types

  1. Additional FAR
  2. Purchasable FAR
  3. Floating FAR

1) Additional FAR

Additional FAR refers to an increase in the allowable floor area of a building beyond the standard zoning regulations. This type of FAR is typically granted through a zoning variance or special permit.

Additional FAR, as provided in the Master Plan may also be examined with a view to provide flexibility and also to utilize the scarce urban land optimally.

Flexible range of FAR on a site may be based upon its Additional FAR Factor which is a product of ‘creativity’ and ‘context’.

  • Creativity can be defined by design parameters such as urban form, parking provision, pedestrian safety, concern for the poor through induced informal activities, and provisions for evacuation during an emergency due to disaster. It also includes the impact of the design on essential services and environment. As a principle, the additional FAR should not result in a negative impact on the essential services and environment.
  • Locational attributes, of the site being assigned additional FAR, refer to its location with respect to land use as given in the approved Master/Zonal/Layout Plan (as the case may be), accessibility, level of congestion on the approach road and nearness to a heritage building if any.


a = Parking provision value
b = Disaster emergency provision value
c = Urban Form value
d = Pedestrian Safety value

e = Induced informal activities value
x = Impact on essential services value
y = Impact on environment value
m = Land Use value
n = Accessibility (Right of way of the approach road) value
o = Congestion (Mobility index in terms of travel speed) value
p = Heritage Value

2) Purchasable FAR

This type of FAR allows a property owner to purchase the right to build additional floor area beyond the standard zoning regulations. This type of FAR is often used as a way for cities to generate additional revenue.

Provision of purchasable FAR in Group Housing, Commercial, Institutional, and Industrial, Sport and amusement complex, recreational greens and Low Density Sports plot may be considered, where:

  1. The Plots exist on ‘24mtrs. and above’ wide road.
  2. The construction has not started, or
  3. The allottee wants to construct a new additional building within the limits of permissible ground coverage, or
  4. The allottee wants to construct new building on the vacant plot, or
  5. The allottee has already constructed building within purchasable F.A.R limits, or
  6. Purchasable F.A.R may be allowed on minimum 18.0mtrs. road width and above road width for institutional and industrial use.

Explanation: The Purchasable FAR shall be allowed up to the maximum limit of the applicable FAR in the Building Regulations.

i) Purchasable may FAR be allowed with the following provision / conditions:

  1. No construction shall be allowed beyond the limit of maximum permissible ground Coverage.
  2. Parking facilities shall be provided within the plot as per the provisions of the building bylaws.
  3. No objection certificate from the Airport Authority of India/ Competent Authority shall be obtained for the height of the building.
  4. Structure design duly checked and verified by the I.I.T/ N.I.T./ Government Engineering College shall be submitted along with the proposal in case where additional floors are being proposed.
  5. No objection certificate for Fire Safety and Environmental Clearance shall be obtained from the Competent Authorities.
  6. Purchasable FAR shall be applicable only on the basis of assessment of planned and available physical infrastructure.
  7. Use of purchaseable FAR shall be governed by the terms and conditions of lease deed.
  8. In case where purchasable FAR is allowed, the Authority shall permit increase in the height of building as per requirement.
  9. Additional proportionate residential units shall be allowed on purchaseable FAR for Group Housing.
Note –
  • Purchasable FAR is an enabling provision. It shall not be allowed to any Allottee as a matter of right.
  • With the consideration of Traffic density, conditions of approach road, availability of physical infrastructure, distance from the protected area and heritage sites or in the light of planning the Authority may identify the zones/ areas where purchasable FAR shall not be allowed.
  • In case of mixed land use permitted in any pocket/plot: Permissible FAR for various uses shall be as applicable for respective use including the purchasable FAR The total FAR in the pocket/plot shall be subject to the overall permissible FAR for the pocket/plot. Purchasable FAR shall be calculated on the basis of the FAR of the individual uses within that pocket/plot.

3) Floating FAR

Floating FAR refers to the concept of allowing a building’s floor area to exceed the standard FAR if certain criteria are met. For example, a building may be allowed to exceed the standard FAR if it includes green spaces, public amenities, or meets certain sustainability standards.

  • The Authority shall allow development by restricting / regulating height of the building width of abutting road and plot sizes.
  • This method is based on the carrying capacity analysis of the infrastructure planned.
  • In keeping with the norm in the provision of infrastructure adjusted to the percentage, plot owners shall be permitted to use the additional FAR on payment basis.

i) Basis for increasing FAR:

  • Carrying Capacity analysis tool is useful to rationalise fixation of FAR including increase in given FAR. Two major determining factors should be considered:
V/C (V= volume, C= capacity)
  • V/C: optimum level is 0.8; it can be relaxed upto 0.9. Above 0.9 is dysfunctional and 1.0 is not desirable.
LPCD of piped water supply
  • The planned LPCD should be as per the minimum of norm i.e. 135 litres. However, the density is to be capped by the Development/ Master Plan as per the threshold.

Note – Assignment of Values for flexible FAR and other calculations may be referred from URDPFI Guidelines, 2014

Each of these types of FAR serves a different purpose, and the appropriate type to use can depend on a number of factors, including the specific zoning regulations, the goals of the city, and the needs of the property owner.

Related video

Leave a Reply

Your email address will not be published. Required fields are marked *

error: Content is protected !!