How much floor spaces can we build?

Are you aware how much floor areas are allowed to be constructed on the lot you bought? Did you know the answer before purchasing the property or did you find out about it only after the purchase?  

There are numerous laws, referral codes, rules and regulations, departmental memorandum circulars as well as local government zoning ordinances that determine how much floor spaces can be built. In addition, contracts entered into by private parties such as the master deeds of restriction in private subdivisions, estates and business districts may carry more consensual conditions or limitations

Primary basis and considerations

Presidential Decree No. 1096, commonly known as the National Building Code of the Philippines (NBCP), is the main source of such information. Promulgated in 1977, PD 1096 superseded Republic Act No. 6541 or “An Act to Ordain and Institute a National Building Code of the Philippines” and was issued to create a standard basis for the design, construction and occupancy of various structures. To complement the NBCP, its “Implementing Rules and Regulations” (IRR) was adopted to further clarify the legal provisions found in PD 1096. This IRR had been updated in 2004 to make it more relevant with the times.

The NBCP and its IRR define how the maximum allowable floor areas are calculated and could be increased, if desired. The maximum height and number of floors are among the important factors that have to be considered. Additionally, the location of the property, nature of planned use, type of occupancy, site occupancy percentages, size and dimension of courtyards, open spaces requirement within the lot, light and ventilation, firewall provisions, road right-of-way width fronting the lot, and other special conditions like airport aerodrome all need to be taken into considerations.

In addition to the NBCP, cities and municipalities also have their own zoning ordinances that prescribe the maximum allowable buildable floor spaces. It is usually based on nature of use, types of structures allowed within low, medium and high-density areas, and building height. 


Technically, the Allowable Maximum Total Gross Floor Area (TGFA) is derived using the Building Height Limit (BHL) multiplied by the Allowable Maximum Building Footprint (AMBF), and adjusted accordingly by the Allowable Maximum Volume of Building (AMVB). [For more details, refer to the provisions, tables and illustrations found in Sections/Rules 7 and 8 of the NBCP and its IRR]

Another method of prescribing maximum floor area is the “Floor-Lot Area Ratio (FLAR)”.  It is a measure of the building size and can be found in the updated NBCP IRR. It denotes the maximum allowable floor area permitted to be constructed on a particular lot, and reflected as a Ratio. 

FLAR = maximum allowable floor area / lot area

To illustrate: FLAR of 3 on a 1000 sqm lot means a maximum 3000 sqm. of floor area may be built thereon.

The FLAR concept is widely used in other countries and known by other names too like Floor Area Ratio (FAR) in the US and Canada, Plot Ratio or Site Ratio in UK and other British Commonwealth countries, and Floor Space Ratio in Australia and Canada. 

Given its extensive usage, it is not surprising that significant differences in the FLAR’s calculations and applications have been noted around the world. Nevertheless, their commonality is that non-occupied spaces are excluded from its calculation, like parking slots, driveways and ramps, power, mechanical and sanitary utility equipment rooms, elevator shafts, fire stairs and open roof decks.


The higher the maximum allowable floor space, the higher is the property value. With land prices on the rise, it is imperative that special attention be given to knowing the maximum allowable floor area before acquiring the lot. 

However, due to the complicated technical and legal requirements as well as numerous provisions that need to be considered collectively, it is best to engage the services of an expert. Sa Arkitekto – Sigurado.


Henry L. Yap is an Architect, Environmental Planner, Real Estate Practitioner and former Professorial Lecturer.