Lesson 4 · 7 min read · Last reviewed
Zoning Classifications Philippines: FAR, PSO, Density Limits
Residential, commercial, mixed-use zones. How to compute Floor Area Ratio (FAR), Percentage of Site Occupancy (PSO), and buildable area under PH zoning ordinances.
Quick Answer
Philippine zoning categorizes land into residential (R-1, R-2, R-3, R-4), commercial (C-1, C-2, C-3), industrial, and special-use zones. Each zone has a Floor Area Ratio (FAR) limit, a Percentage of Site Occupancy (PSO), height restrictions, and setback requirements. Buildable area = Lot Area × PSO. Maximum total floor area = Lot Area × FAR. Zoning classifications come from the LGU's Comprehensive Land Use Plan (CLUP).
Floor Area Ratio (FAR) Computation
“Floor Area Ratio (FAR) shall be the ratio of the Gross Floor Area (GFA) of a building to the Total Lot Area (TLA). FAR shall be used as the principal measure for regulating building bulk and density. Maximum FAR = GFA / TLA. The allowable FAR for each zone shall be specified in the zoning ordinance.”
What This Means
Floor Area Ratio (FAR) determines how much total building area you can construct relative to your lot size. Formula: Maximum GFA = Lot Area × FAR. Example: a 500 sqm lot with FAR 3.0 allows up to 1,500 sqm of gross floor area. You can distribute this vertically: 5 floors × 300 sqm each, or 10 floors × 150 sqm each. FAR varies by zone: low-density residential (FAR 1.0-1.5), medium-density (FAR 2.0-3.0), commercial (FAR 4.0-8.0), CBD (FAR 10.0+). Developers use FAR to determine maximum building size and project feasibility.
- FormulaMaximum GFA = Lot Area × FAR
- FAR limits TOTAL building bulk, not height directly
- Low-density residentialFAR 1.0-1.5 (small buildings)
- CommercialFAR 4.0-8.0 (mid/high-rise possible)
- CBD/mixed-useFAR 10.0+ (skyscrapers)
Real-World Scenario
A developer owns a 1,000 sqm lot zoned as C-2 Commercial with a FAR of 5.0. They want to build a 12-story office building with 450 sqm of floor area per floor.
Does this building comply with the FAR limit?
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Maximum GFA = 1,000 sqm × 5.0 = 5,000 sqm. Proposed GFA = 12 floors × 450 sqm = 5,400 sqm. The proposed building EXCEEDS the FAR limit by 400 sqm. Options: (1) Reduce to 11 floors (4,950 sqm, within limit), (2) Reduce floor area per floor to 416 sqm (416 × 12 = 4,992 sqm), or (3) Apply for FAR variance from the LGU (not guaranteed). The developer should also check PSO and height limits separately.
Percentage of Site Occupancy (PSO)
“The maximum Percentage of Site Occupancy (PSO) or Maximum Building Footprint shall be the maximum percentage of the lot area that may be covered by the building at ground level. The remaining area shall be kept as open space for setbacks, parking, landscaping, or other open space requirements.”
What This Means
PSO determines the maximum ground coverage: how much of the lot the building footprint can occupy. Formula: Building Footprint = Lot Area × PSO. The remaining area (100% - PSO) is mandatory open space for setbacks, parking, driveways, and landscaping. Common PSO limits: residential (60-70%), commercial (80-90%), industrial (70-80%). PSO and FAR work together: PSO limits horizontal spread, FAR limits total building volume. A high FAR with low PSO means you must build UP (tall and skinny), not OUT (wide and squat).
- FormulaMax Building Footprint = Lot Area × PSO
- Open Space = Lot Area × (1 - PSO), must remain unbuilt
- Residentialtypically 60-70% PSO
- Commercialtypically 80-90% PSO
- PSO + FAR together determine building shape and height
Real-World Scenario
A 500 sqm residential lot has the following restrictions: PSO = 60%, FAR = 2.0, maximum height = 12 meters (approximately 4 stories). A homeowner wants to maximize their building.
What is the maximum building configuration allowed?
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Max footprint: 500 × 60% = 300 sqm (ground floor area). Max GFA: 500 × 2.0 = 1,000 sqm (total building area). Max floors from GFA: 1,000 ÷ 300 = 3.33 floors, but max height allows 4 floors. So the constraint is GFA, not height. Maximum building: 3 floors at 300 sqm each (900 sqm GFA) + a 4th floor of only 100 sqm (penthouse/roof deck) = 1,000 sqm total. Open space: 500 - 300 = 200 sqm (for setbacks, garden, parking).
Building Setback Computations
“The minimum setback requirements for buildings shall be as follows: The required setback from the property line shall be measured at right angles to the lot boundary. No part of any building shall be erected within the required setback area. The specific setback distances shall be prescribed by the local zoning ordinance or, in its absence, the National Building Code standards.”
What This Means
Setbacks are mandatory distances between the building and property boundaries. They ensure light, ventilation, fire safety, and access. Standard minimum setbacks (vary by zone and building height): Front: 3-5m, Side: 2-3m, Rear: 2-3m. For taller buildings, setbacks increase. The buildable area after setbacks determines the actual footprint: Buildable Area = (Lot Width - Left Setback - Right Setback) × (Lot Depth - Front Setback - Rear Setback). For irregular lots, each boundary requires its own setback computation.
- Front setbacktypically 3-5m from the road/front boundary
- Side setbackstypically 2-3m from each side boundary
- Rear setbacktypically 2-3m from the back boundary
- Buildable area = area remaining after all setbacks are applied
- Taller buildings require larger setbacks (stepped back at higher floors)
Real-World Scenario
A rectangular lot is 15m wide × 25m deep (375 sqm). The zoning requires: front setback 5m, side setbacks 3m each, rear setback 3m. The PSO is 60% and FAR is 2.0.
What is the maximum building footprint considering setbacks?
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Buildable width: 15m - 3m - 3m = 9m. Buildable depth: 25m - 5m - 3m = 17m. Buildable area from setbacks: 9 × 17 = 153 sqm. PSO-based max footprint: 375 × 60% = 225 sqm. The SETBACK constraint (153 sqm) is more restrictive than PSO (225 sqm). The actual max footprint is 153 sqm. Max GFA: 375 × 2.0 = 750 sqm. Possible floors: 750 ÷ 153 = 4.9 → maximum 4 full floors at 153 sqm + a partial 5th floor of 138 sqm (if height permits).
Frequently Asked Questions
What happens if my existing building exceeds the current FAR or PSO limit?
Existing buildings built before the current zoning ordinance took effect are typically "grandfathered" as non-conforming uses/structures. They can continue to exist but usually cannot be expanded, altered significantly, or rebuilt if demolished/destroyed beyond 50%. If you want to renovate or add floors, you must comply with the current FAR and PSO limits. Check your LGU's zoning ordinance for specific non-conforming structure rules.
How do basements and parking floors affect FAR computation?
Rules vary by LGU, but generally: basements used for parking are NOT counted in GFA/FAR (they are below grade). Above-ground parking floors may or may not be counted: some LGUs exclude "dedicated parking floors" from GFA computation. Mechanical floors (for HVAC, water tanks) are typically excluded if they are not habitable. Always verify with the local zoning/building office which areas are FAR-exempt in your jurisdiction.
What is the relationship between number of floors and building height in meters?
Standard floor-to-floor height: residential = 2.7-3.0m, commercial/office = 3.5-4.0m, retail ground floor = 4.5-6.0m. So a 10-story residential building is approximately 30m tall, while a 10-story commercial building might be 40m. Zoning ordinances may limit height in METERS (not floors), so the same height limit allows more residential floors than commercial floors. Always check both the floor limit AND the meter limit: whichever is more restrictive controls.
Lesson 4 of 6