Before a single column is sized or a beam designed, every structural engineer in the Philippines must answer the same two questions: how heavy is the building itself, and how heavy will everything inside it be?
Dead loads and live loads are the foundation of every structural calculation. Get them wrong — underestimate either one — and every downstream result is compromised: undersized beams, inadequate columns, under-designed foundations. Get them right, and every subsequent analysis has a solid base.
This guide covers the complete gravity load requirements under NSCP 2015 Sections 204 and 205 — unit weights of common Philippine construction materials, minimum live loads by occupancy type, roof live loads, and how to combine them into factored design loads.
This guide is based on NSCP 2015 (7th Edition): Section 204 (dead loads and densities), Section 205 (live loads), and Section 203 (load combinations). All values are for design purposes — always verify against the current code edition and applicable local amendments.
Dead loads are the permanent, fixed weight of all structural and non-structural components of a building — the weight that never changes once the building is built. Every slab, beam, column, wall, floor finish, ceiling, and roofing system contributes to the total dead load that the structure must carry at all times.
Think of dead load as the weight of the building talking to itself — the concrete, steel, blocks, tiles, and plaster that don't go anywhere. Live load is the weight of people, furniture, and stored goods that come and go. Both must be calculated before any member can be sized.
Per NSCP 2015 Section 204, the following unit weights apply to common structural materials in Philippine construction:
| Material | Unit Weight (kN/m³) | Unit Weight (kgf/m³) | Notes |
|---|---|---|---|
| Reinforced Concrete (RC) | 23.6 | 2,406 | Standard for all RC slabs, beams, columns. Many engineers use 24 kN/m³ |
| Plain Concrete | 22.6 | 2,304 | Unreinforced: footings, mass concrete |
| Lightweight Concrete | 15.7–18.8 | 1,600–1,920 | Varies by aggregate; verify with supplier |
| Structural Steel | 77.0 | 7,849 | All carbon steel structural shapes |
| Stainless Steel | 77.2 | 7,870 | |
| Aluminum | 26.7 | 2,722 | Roofing, cladding, curtain walls |
| Cast Iron | 70.7 | 7,208 |
| Material | Unit Weight (kN/m³) | Notes |
|---|---|---|
| Concrete Hollow Block (CHB) — 150mm | 16.5 | Most common Philippine wall material; verify with block density |
| Concrete Hollow Block (CHB) — 100mm | 15.7 | Partition walls |
| Solid Concrete Block | 21.2 | Heavier than CHB; used at base of walls |
| Clay Brick (solid) | 19.0–21.0 | Uncommon in modern PH construction |
| AAC Block (Autoclaved Aerated Concrete) | 6.0–10.0 | Depends on density grade; lighter than CHB |
| Cement Plaster / Mortar | 20.4 | Applied both faces of CHB wall: +0.5–1.0 kPa total |
| Gypsum Board (12mm) | 0.11 kPa/m² | Per unit area, not volume |
These are commonly expressed as load per unit floor area (kPa) rather than unit weight:
| Finish / Component | Dead Load (kPa) | Notes |
|---|---|---|
| Ceramic / porcelain tile (10mm) + mortar bed (25mm) | 0.90–1.20 | Most common Philippine floor finish |
| Granite / marble tile + mortar bed | 1.10–1.50 | Heavier than ceramic |
| Hardwood flooring (25mm) | 0.20–0.30 | Less common in PH residential |
| Cement screed only (25mm) | 0.50 | Topping on structural slab |
| Suspended ceiling (light metal + gypsum board) | 0.40–0.60 | Applied to underside of slab |
| Suspended ceiling (concrete plaster) | 0.70–1.00 | Heavier traditional ceiling |
| Pre-painted GI roofing sheet (0.5mm) | 0.05–0.10 | Light; uplift governs, not gravity |
| Concrete roof tile | 0.55–0.75 | Heavier; must be carried by purlins |
| Insulated metal roofing (sandwich panel) | 0.15–0.25 | Varies by panel thickness |
| Waterproofing membrane | 0.05–0.15 | Roof deck or wet area treatment |
In practice, a typical Philippine residential floor assembly contributes 4.5–5.5 kPa of dead load per floor: ~3.0 kPa from the 125mm RC slab, ~1.2 kPa from tile and mortar, and ~0.5 kPa from ceiling. This is the number most Philippine residential engineers start with before adding live load on top. Always compute it — never assume.
Using the unit weight of plain concrete (22.6 kN/m³) instead of reinforced concrete (23.6 kN/m³) for structural slabs and beams. The difference is small per element — but across an entire 5-storey building, it accumulates into a significant underestimate of column and foundation loads. Always use 23.6 kN/m³ (or the conservative 24 kN/m³) for any concrete member with reinforcing steel.
Live loads are the variable, movable loads imposed by building occupants, furniture, stored goods, and equipment. Unlike dead loads, live loads change over time — a warehouse floor that holds office furniture today might hold heavy pallet racking tomorrow.
NSCP 2015 Section 205 specifies minimum design live loads by occupancy. These are lower bounds — if your actual expected loading exceeds the code minimum, design for the actual load.
| Occupancy / Use | Live Load (kPa) | Live Load (kgf/m²) |
|---|---|---|
| Residential | ||
| Private rooms, living areas, bedrooms | 1.9 | 194 |
| Corridors (above ground floor, serving residential) | 3.8 | 388 |
| Balconies and exterior decks | 3.0 | 306 |
| Office and Commercial | ||
| Office areas (standard) | 2.4 | 245 |
| Lobbies, ground floor corridors | 4.8 | 490 |
| Retail stores (ground floor) | 4.8 | 490 |
| Retail stores (upper floors) | 3.6 | 367 |
| Restaurants and dining areas | 4.8 | 490 |
| Assembly and Public | ||
| Assembly areas — fixed seats | 2.9 | 296 |
| Assembly areas — movable seats, standing | 4.8 | 490 |
| Corridors, lobbies serving assembly | 4.8 | 490 |
| Institutional | ||
| Hospital patient rooms | 2.0 | 204 |
| Hospital operating rooms, laboratories | 2.9 | 296 |
| Schools — classrooms | 2.0 | 204 |
| Schools — corridors above ground floor | 3.8 | 388 |
| Storage and Industrial | ||
| Light storage (shelves, files) | 6.0 | 612 |
| Heavy storage | 12.0 | 1,224 |
| Garage — passenger vehicles only | 2.4 | 245 |
| Circulation | ||
| Stairs and exitways (all occupancies) | 4.8 | 490 |
| Fire escapes (residential) | 3.0 | 306 |
Applying the residential live load of 1.9 kPa to stairways, corridors, and lobbies. These circulation spaces require 3.8–4.8 kPa — more than double the residential room value — because they concentrate foot traffic from multiple units simultaneously. A residential stairway designed for 1.9 kPa is significantly under-designed and will fail code review.
Roof live loads account for maintenance workers, equipment placement, and construction loads during repairs. They vary with tributary area — larger roof areas have lower minimum values because simultaneous uniform loading is less probable.
| Tributary Roof Area (m²) | Minimum Roof Live Load (kPa) | Notes |
|---|---|---|
| Up to 18.6 m² | 1.44 | Small roof sections, canopies |
| 18.6 to 55.7 m² | 1.20 | Interpolate between 1.44 and 0.96 |
| Over 55.7 m² | 0.96 | Large roof spans |
| Accessible roof deck / terrace | Same as occupancy served (min. 1.9 kPa) | Treat as floor live load if used as terrace |
A typical Philippine residential roof covering more than 55.7 m² uses a roof live load of 0.96 kPa — this represents a maintenance worker walking on the roof, not a crowd. But if the roof is designed as an accessible terrace or rooftop garden, the floor live load (1.9 kPa minimum for residential) governs instead — and the structural dead load from planters, paving, and soil must be added on top of that.
For members with large tributary areas carrying loads of 4.8 kPa or less, NSCP 2015 permits a live load reduction. The probability of full simultaneous loading across a large area is lower than across a small one — this statistical reality is captured in the reduction formula:
L = L₀ × (0.25 + 4.57 / √AT)
L = reduced live load (kPa) · L₀ = unreduced (tabulated) live load (kPa) · AT = tributary area (m²)
Reduction limits:
Live load reduction is often skipped in Philippine practice — especially for residential and small commercial projects where tributary areas rarely hit the 37.16 m² threshold for individual beams. It becomes significant for columns in multi-storey buildings, where the accumulated tributary area for lower-floor columns easily exceeds the threshold. Applying reduction there can meaningfully reduce column sizes and foundation loads.
Dead loads and live loads don't act on a structure in isolation — they combine with wind, seismic, and other loads in ways defined by NSCP 2015 Section 203. The load combination that produces the most critical effect in each structural member governs the design.
NSCP 2015 provides combinations for both LRFD (Load and Resistance Factor Design) and ASD (Allowable Stress Design).
For LRFD, structural members are sized so their design strength ≥ factored demand. The governing combination for gravity loads is almost always Combination 2:
| # | Combination | When It Governs |
|---|---|---|
| 1 | 1.4D | Rarely governs — only when live load is very small relative to dead load |
| 2 | 1.2D + 1.6L + 0.5Lr | Governs for most interior beams and columns under standard gravity loading |
| 3 | 1.2D + 1.6Lr + (L or 0.5W) | Governs for roof members when roof live load is large |
| 4 | 1.2D + 1.0W + L + 0.5Lr | Governs for lateral systems in typhoon-exposed buildings |
| 5 | 0.9D + 1.0W | Governs for uplift check — is dead load enough to prevent overturning? |
| 6 | 1.2D + 1.0E + L | Governs for seismic design in Zone 4 |
| 7 | 0.9D + 1.0E | Governs for seismic uplift check |
ASD is still widely used in the Philippines for steel connection design, foundation design, and some timber members. The governing combination for gravity-only loading is typically Combination 2:
| # | Combination |
|---|---|
| 1 | D |
| 2 | D + L |
| 3 | D + Lr (or S or R) |
| 4 | D + 0.75L + 0.75Lr |
| 5 | D + (W or 0.7E) |
| 6 | D + 0.75L + 0.75(W or 0.7E) + 0.75Lr |
| 7 | 0.6D + W |
| 8 | 0.6D + 0.7E |
For most Philippine residential and commercial RC frame buildings, engineers use LRFD (strength design) per ACI 318 for concrete member design. ASD is typically used only for foundation bearing pressure checks, steel connection design, or when explicitly required by the project specification. When in doubt, use LRFD — it is the primary design philosophy of NSCP 2015.
Let's apply Sections 204, 205, and 203 to a real Philippine design scenario: sizing the factored gravity load on a simply supported beam at the second floor of a residential building.
Beam B1 at 2nd floor · Span: L = 6.0 m (simply supported) · Tributary width: s = 3.0 m
Slab thickness: 125 mm RC · Floor finish: ceramic tile + mortar bed · Suspended ceiling below
Occupancy: Residential (private rooms)
| Component | Calculation | Load (kPa) |
|---|---|---|
| RC slab (125mm) | 0.125 m × 23.6 kN/m³ | 2.95 |
| Ceramic tile + mortar bed (35mm total) | 0.035 m × 20.4 kN/m³ | 0.71 |
| Suspended ceiling | allowance | 0.50 |
| Total Dead Load (wD) | 4.16 kPa |
Occupancy: residential private rooms → L₀ = 1.9 kPa
Check live load reduction (Section 205.7): AT = 6.0 × 3.0 = 18.0 m² < 37.16 m² → no reduction permitted
| Load Type | Calculation | Line Load (kN/m) |
|---|---|---|
| Dead load | 4.16 kPa × 3.0 m | 12.48 |
| Live load | 1.9 kPa × 3.0 m | 5.70 |
Note: Beam self-weight is added separately based on the assumed beam cross-section and verified iteratively.
wu = 1.2 × 12.48 + 1.6 × 5.70 = 14.98 + 9.12 = 24.10 kN/m
Mu = wu × L² / 8 = 24.10 × 6.0² / 8 = 108.5 kN·m
This factored moment is the design demand that the beam's nominal moment capacity (ϕMn per ACI 318 / NSCP Section 400) must equal or exceed. From here, the designer selects a beam width and depth, computes the required steel area, and checks deflection under service loads (using unfactored D + L).
For a 108.5 kN·m factored moment using f'c = 28 MPa and fy = 415 MPa (Grade 60 rebar), a typical beam size would be 250 × 400 mm with approximately 3–4 pcs of 20mm main bars at the bottom. Always verify beam depth controls deflection (L/16 rule of thumb for simply supported = 375 mm minimum) and check shear at supports.
For office buildings and adaptable floor plans, NSCP permits treating movable partitions as a uniform live load addition of 1.0 kPa when the partition layout is not fixed. Many engineers omit this entirely on office floors, resulting in beams that are under-designed for the actual building use. If permanent walls are shown on the plan, calculate their actual weight per linear meter and apply as a line load on the supporting beam.
A roof designed as a terrace or rooftop garden is not a "roof" for live load purposes — it's an occupied floor. Apply the floor live load (minimum 1.9 kPa for residential, 4.8 kPa for assembly use) plus the dead load of the paving, soil, planters, and waterproofing. This combination is frequently missed on residential condo projects where the top floor becomes a penthouse terrace.
Stairs, exitways, and fire escapes are explicitly excluded from live load reduction under NSCP 205.7, regardless of tributary area. The 4.8 kPa live load for stairs must be used at full value in all combinations. This is a life-safety requirement — stairways must remain passable when the entire occupant load evacuates simultaneously.
The most dangerous calculation error: applying LRFD load factors (1.2D + 1.6L) and then checking against allowable stresses (ASD capacity). The two methods are not interchangeable. If you design in LRFD, use factored loads and compare against ϕMn, ϕVn. If you use ASD, use unfactored service loads (D + L) and compare against allowable stress or allowable capacity.
The BuildX NSCP Kit app gives you instant access to NSCP 2015 load tables, load combinations, seismic base shear, wind load computation, and design aids — organized by section, searchable, and available offline. Used by licensed Philippine engineers on every AEDO project.
Correct gravity load analysis is the starting point — but a complete structural design also requires wind load analysis (Section 207), seismic base shear (Section 208), member sizing, and permit-ready drawings. AEDO Construction handles all of it.
Dead loads and live loads are the inputs to every structural calculation. Underestimate them and every downstream result — beam sizes, column capacities, foundation depths — is built on a false foundation. The code provides the minimums. Experience tells you when to exceed them.
AEDO Construction applies the full NSCP 2015 gravity load framework on every project — no shortcuts, no assumed values, no skipped combinations.
If you need structural analysis or design for your project, AEDO Construction is ready to help.
Per NSCP 2015 Table 205-1, the minimum live load for private residential rooms (bedrooms, living rooms, dining areas) is 1.9 kPa (195 kgf/m²). However, other areas of a residential building require higher values: corridors above the ground floor require 3.8 kPa, stairs and exitways require 4.8 kPa, and balconies require a minimum of 3.0 kPa. Always check the specific area type, not just the building occupancy.
NSCP 2015 Section 204 specifies the unit weight of reinforced concrete as 23.6 kN/m³. In Philippine engineering practice, many designers round this to 24 kN/m³ as a slightly conservative value, which is acceptable. Never use the plain concrete value of 22.6 kN/m³ for reinforced concrete members — the difference accumulates significantly across a multi-storey building's column and foundation design.
NSCP 2015 Section 203 specifies the following LRFD combinations. For gravity-only loading, two combinations typically govern: (1) 1.4D — governs when dead load dominates — and (2) 1.2D + 1.6L + 0.5Lr — governs for most beams and columns under standard occupancy loading. For members where lateral loads (wind or seismic) are significant, combinations 4, 5, 6, and 7 must also be checked. The highest factored demand from all applicable combinations governs the design.
NSCP 2015 Section 205.7 permits live load reduction when the tributary area AT ≥ 37.16 m² and the live load is 4.8 kPa or less. The reduced live load is L = L₀ × (0.25 + 4.57/√AT). The reduction may not bring the live load below 50% of L₀ for members supporting one floor, or 40% for members supporting two or more floors. Reduction is not permitted for: assembly occupancies, areas with live loads exceeding 4.8 kPa, roof live loads, stairs, or exitways.
CHB walls sitting on a beam are applied as a line load (kN/m), not a uniform area load. Calculate the wall's weight per meter of length: unit weight of CHB × wall thickness × wall height. For a standard 150mm CHB wall at 2.7m height: approximately 16.5 kN/m³ × 0.15m × 2.7m ≈ 6.7 kN/m, plus 0.5–1.0 kN/m for plaster on both faces. This line load is added to the dead load tributary to the beam. Openings (doors, windows) reduce the effective wall load proportionally.