🇵🇭 NSCP & DPWH Specs · Free · No Signup

Philippine CHB & Cement Calculator

Enter your wall dimensions and get an exact hardware shopping list — CHBs, cement bags, sand, rebar (kabilya), and tie wire — with a PHP budget estimate. Typhoon-ready specs included.

🧱 4-Inch & 6-Inch CHB 🏗️ NSCP Typhoon Specs ⚙️ Rebar & Tie Wire ₱ PHP Budget Estimator ✅ 10% Wastage Buffer
CHB Thickness (Sukat ng Biswal)
Reinforcement Spec (NSCP Standard)
Additional Options
Calculate Plastering — Both Sides Adds cement + sand for 12mm plaster coat on each face
Include 10% Wastage Buffer Standard practice — recommended for all estimates
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Enter Dimensions to Start
Input your wall's length and height above to generate your hardware shopping list.
CHB Selection Guide

4-Inch vs. 6-Inch CHB — Which Should You Use?

Per NSCP (National Structural Code of the Philippines) and DPWH Item 1046 standards, CHB thickness determines structural suitability. Using the wrong size violates code and creates dangerous walls.

4-Inch CHB
100mm · Interior Use Only
  • Interior room partition walls
  • Bathroom and toilet enclosures
  • Temporary room dividers
  • Non-structural separation walls
⚠️
Not permitted for exterior walls, perimeter fences, or any load-bearing structure.
6-Inch CHB
150mm · Exterior & Structural
  • All exterior perimeter walls (pader)
  • Firewalls and boundary fences
  • Load-bearing masonry walls
  • Walls below ground (nakabaon)
  • Walls exposed to typhoon lateral loads

📚 Educational reference. CHB thickness requirements above follow NSCP 2015 and common DPWH practice. Local building officials and your structural engineer have final authority on material specifications. Some municipalities may impose stricter minimum requirements.

Structural Reinforcement Constants

Gabay sa Kabilya — Typhoon-Ready Rebar Specifications

In the Philippines, walls face intense lateral loads from earthquakes along fault lines and 250+ km/h typhoon winds. Steel rebars (kabilya) must be laid continuously and tied at every single intersection using #16 G.I. Tie Wire (alambre). Unreinforced CHB walls will fail.

Parameter Standard Typhoon-Resistant Spec High-Risk / Perimeter Fence Spec
Vertical Bars Diameter 10mm deformed steel bar 12mm deformed steel bar
Vertical Spacing Every 40cm (every 2 block lengths) Every 40cm (every 2 block lengths)
Horizontal Bars Diameter 10mm deformed steel bar 10mm deformed steel bar
Horizontal Spacing Every 60cm (every 3 block layers) Every 40cm (every 2 block layers)
Concrete Cover Protection 25mm clear cover from wall face 50–60mm clear cover (if buried / in soil contact)
Lapping Splices Minimum 30× bar diameter (~30cm overlap) Minimum 30× bar diameter (~30cm overlap)
⚠️
DPWH Stiffener Column Requirement: Any wall segment longer than 3.0 meters must include a reinforced concrete stiffener column (minimum 150mm × 300mm cross-section with 4 pieces of 12mm bars). Lintel beams must also be provided above every door and window opening.

📚 Educational reference only. The specifications above are based on NSCP 2015 and DPWH standard guidelines as commonly applied in Philippine residential construction. Actual structural requirements depend on site-specific conditions including soil classification, seismic zone, wall height, and applied loads. These are rule-of-thumb starting points — not a substitute for a structural analysis prepared by a licensed civil or structural engineer (PRC-registered). For any structure requiring a building permit, NSCP compliance must be certified by an engineer of record.

Long-Term Care

CHB Wall Maintenance & Local Troubleshooting

A concrete wall in the tropical Philippine climate faces intense moisture, UV, and seismic movement. These are the problems every local panday has seen and how to prevent them.

🌧️
The "Ulan-Binit" Cycle — Hairline Cracks
Extreme swings between monsoon downpours and blinding midday sun cause concrete to expand and contract, forming hairline cracks. Always use clean, river-washed sand (binistay) for plastering. Never use mountain sand — its high clay content causes massive shrinkage and cracking.
✅ Remedy: Seal cracks under 2mm immediately with elastomeric waterproofing paint (Boysen Plexibond or Davies Megacryl) before water reaches the internal kabilya.
🎨
"Alcali" and Paint Peeling (Nagtatuklap na Pintura)
Freshly plastered concrete is highly alkaline. Painting too early causes salts to react with the paint coating, creating white powdery stains (efflorescence), bubbles, and peeling. Plastered walls must cure for 14 to 28 days, regularly doused with fresh water (pina-pagaling).
✅ Remedy: Apply a chemical neutralizing wash or dedicated concrete primer/sealer before any paint coat.
🌊
Coastal Rust (Kalawang malapit sa Dagat)
Salt spray in coastal areas accelerates concrete carbonation and oxidizes the internal kabilya. For structures within 1km of the sea, never use beach sand under any circumstances. Engineers specify a thicker 25mm plaster coat and a denser Class A mix to shield steel bars from chloride intrusion.
✅ Prevention: Use only washed river sand and apply a penetrating concrete sealer annually in coastal environments.
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Mix Ratios — Class A vs. Class B
Class A (1:3 ratio): 1 part cement to 3 parts sand. Used for structural grouting, core fill, plastering firewalls, and below-ground walls. Maximum waterproofing and strength. Class B (1:4 ratio): The economic standard for general block-laying mortar on interior partitions.
✅ Default: Always use Class A for exterior walls, firewalls, and any below-grade masonry.
Frequently Asked Questions

Mga Madalas Itanong — PH Construction FAQ

A standard CHB has a face size of 40cm × 20cm (0.08 sqm per block). That means 12.5 blocks cover one square meter of wall face. With a 10% wastage allowance for cuts, breakage, and mortar adjustments, the practical working estimate is 13 to 14 CHBs per square meter. For example: a 5m long × 2.5m high wall = 12.5 sqm → approximately 172 CHBs with wastage.
For every 100 CHBs using a Class A (1:3 cement-to-sand) mix, you need approximately 3.5 to 4 bags of 40kg Portland cement to cover block-laying mortar joints and core fill grouting. This is the structural minimum — it does not include plastering both faces of the wall, which adds a significant additional cement requirement.
A 4-inch CHB (100mm) is strictly for interior partition walls, toilet enclosures, and temporary room dividers. It is not permitted for exterior or structural use. A 6-inch CHB (150mm) is the mandatory baseline for all exterior perimeter walls, firewalls (pader), boundary fences, and load-bearing masonry structures — per NSCP and DPWH standard specifications.
Yes — absolutely required for any wall built to Philippine seismic and typhoon standards. Unreinforced CHB walls will fail under the lateral loads of a strong typhoon or earthquake. NSCP standards require 10mm deformed steel bars placed vertically every 40cm and horizontally every 60cm (standard spec), tied at every intersection with #16 G.I. Tie Wire. Skipping rebar is a structural code violation.
By default, the calculator shows materials for block-laying mortar and core fill only. Enable the "Calculate Plastering — Both Sides" toggle to add cement and sand for a standard 12mm plaster coat on both wall faces. Note that plastering typically consumes more cement than block-laying itself, because it covers the entire surface area of both faces. Professional estimators always separate these two line items.
Class A (1:3): 1 part cement to 3 parts sand. Used for structural core filling (grout), plastering firewalls, and below-ground masonry. Maximizes waterproofing and compressive strength. Class B (1:4): The default economical ratio used by local pandays for interior block-laying mortar. This calculator uses Class A specs as its base since it follows NSCP structural design standards for typhoon-resistant walls.
Salt spray causes concrete carbonation — the alkaline protection around steel bars breaks down, allowing oxygen and chlorides to reach and rust the internal kabilya. Never use unwashed beach sand for construction. For coastal structures within 1km of the sea, engineers specify a thicker 25mm plaster coat and a Class A mix to create a denser, more impermeable concrete matrix around the steel reinforcement.
As of 2026 retail averages: CHBs run ₱12–₱18 per piece depending on size and location. Portland cement (40kg bags — Republic, Holcim, Eagle brands) retails at ₱260–₱300/bag in Metro Manila and major cities. River sand runs ₱900–₱1,300 per cubic meter. Steel rebar (10mm, 6m length) averages ₱165–₱210 per piece. Island provinces can run 15–25% higher. Use the editable price inputs above to match your local hardware store.

Panday & Karpintero Labor Rates by Region (2025–2026)

Daily rates below reflect typical skilled worker wages in the construction sector. These are above DOLE minimum wage — experienced mason (panday) and carpenter (karpintero) command a premium. Rates vary by project type, contractor arrangement (daily vs. pakiao), and individual experience.

NCR
Metro Manila
Mason (Panday)₱700–₱950
Carpenter₱650–₱850
Foreman₱950–₱1,300
Helper₱500–₱650
DOLE min ₱695/day. Pasay, QC, Marikina at highest demand.
Region IV-A
Calabarzon (Cavite, Laguna, Batangas, Rizal)
Mason (Panday)₱550–₱750
Carpenter₱520–₱700
Foreman₱750–₱1,000
Helper₱450–₱560
DOLE min ~₱545. Urban Cavite/Laguna close to NCR rates.
Region III
Central Luzon (Pampanga, Bulacan, Bataan)
Mason (Panday)₱500–₱700
Carpenter₱480–₱650
Foreman₱700–₱950
Helper₱430–₱530
DOLE min ~₱480. Pampanga & Bulacan lean higher.
Region VII
Central Visayas (Metro Cebu, Bohol, Dumaguete)
Mason (Panday)₱550–₱750
Carpenter₱500–₱680
Foreman₱750–₱950
Helper₱430–₱530
DOLE min ~₱500. Metro Cebu City at upper range.
Region XI
Davao Region
Mason (Panday)₱500–₱700
Carpenter₱480–₱650
Foreman₱700–₱900
Helper₱410–₱510
DOLE min ~₱500. Davao City competitive with Cebu.
Region X
Northern Mindanao (Cagayan de Oro, Iligan)
Mason (Panday)₱460–₱650
Carpenter₱440–₱600
Foreman₱650–₱850
Helper₱390–₱480
DOLE min ~₱475 (updated Dec 2025). CDO fastest-growing.
Other Luzon Provinces
Ilocos, Bicol, MIMAROPA
Mason (Panday)₱420–₱620
Carpenter₱400–₱580
Foreman₱600–₱800
Helper₱360–₱460
DOLE min ₱420–₱470 depending on specific region.
Island Provinces
Palawan, Batanes, Samar, Leyte, Sulu
Mason (Panday)₱400–₱580
Carpenter₱380–₱540
Foreman₱570–₱750
Helper₱340–₱440
Material transport adds cost. Labor sometimes includes board & lodging.
⚠️ Daily Rate vs. Pakiao (Piecework)

Most contractors offer two arrangements: daily rate (araw-araw) or pakiao (lump-sum per wall/area). Pakiao is typically cheaper for the owner when workers are efficient — panday earn more if they're fast. Always clarify which applies to your contract. Unscrupulous contractors may quote daily rate then drag out the timeline. Ask for a written contract with milestone-based payment.

🔢 Quick labor cost estimate for a CHB wall

A 2-person team (1 mason + 1 helper) typically lays 80–120 CHBs per day in standard residential construction. For a 25 sqm wall (~313 CHBs), expect roughly 3–4 working days of team labor. At NCR rates: (₱800 mason + ₱600 helper) × 3.5 days ≈ ₱4,900–₱5,600 in labor for that single wall — separate from materials.

DIY CHB Wall Guide — Can You Lay the Blocks Yourself?

Laying CHB walls is one of the more accessible construction skills for a hands-on homeowner. Below is a complete checklist: what tools you need, the correct process, safety essentials, common beginner mistakes, and — critically — what you should never attempt without a licensed professional.

⚠️ Educational / Planning Reference Only
This guide is for general awareness. CHB wall work on a permitted structure must follow the engineer-approved plans. Deviating from approved rebar layout, spacing, or dimensions may cause structural failure and will fail LGU inspection. When in doubt, follow the engineer's plans — not this guide.
🧰 Tools You Need
  • Mason's trowel — 10" brick trowel for mortar application and joint finishing
  • Spirit level — 4-foot minimum; short levels compound errors over a wall course
  • Mason's line & pins — string stretched between corner blocks guides each horizontal course
  • Rubber mallet — seats blocks without cracking them (never use a metal hammer)
  • Tape measure & chalk line — lay out wall footprint and check openings
  • Mixing drum or batya — hand-mix for small walls; rent a concrete mixer for anything over 50 sqm
  • Wheelbarrow — for moving mortar mix to the wall
  • Angle grinder + diamond blade — cutting CHBs to fit corners and openings (never snap-cut; it shatters)
  • Float / jointer — finish mortar joints before they fully cure
  • Buckets — separate buckets for water, mortar, and rinsing
🦺 Safety — Never Skip These
  • Safety glasses / goggles — cement dust and grinder sparks; CHB chips fly far
  • Cut-resistant gloves — CHB edges are sharp; wet cement causes chemical burns over time
  • N95 dust mask — cement dust is a Class 1 lung irritant; silica in sand is a long-term hazard
  • Steel-toed boots — individual CHBs weigh 8–12 kg each; dropping one on bare feet = broken toes
  • Long sleeves — wet portland cement is highly alkaline and will burn exposed skin after 20+ minutes of contact
  • Hard hat — if any overhead work is happening simultaneously on site
  • Ear protection — for extended grinder use (angle grinder = ~100dB)

Step-by-Step: Laying CHB Walls Correctly

This assumes your footing and grade beams are already cast and cured (minimum 7 days). Do not begin wall-laying on fresh concrete.

1
Wet your CHBs — 4 to 8 hours before laying Dry CHBs aggressively absorb water from mortar, killing the mix before it can cure. Soak them in a drum or spray thoroughly and let them surface-dry. They should look damp but not dripping when laid.
2
Snap the chalk line and dry-lay the first course Before mixing any mortar, set out the first course of blocks without mortar to check fit, plan cuts, and confirm corner positions match your approved plan dimensions.
3
Mix mortar: 1 part cement : 3 parts sand Add water gradually — the mix should hold its shape when squeezed in your fist, but not be crumbly or soupy. Workable time is ~30 minutes; discard any batch that starts to stiffen before use. Never add water to re-temper old mortar.
4
Build the corner leads first Lay 4–5 courses at each corner before filling in between. Corner leads are your level reference — if they're off, the whole wall is off. Check level, plumb (vertical), and range (alignment) at every course of the lead.
5
Apply the bed joint — 10mm thick, full coverage Spread mortar on the top of the previous course (bed joint) using the trowel. 10mm is standard. Do not "furrow" the mortar with a V-groove — full coverage = stronger bond.
6
Butter the end of each block (head joint) Apply mortar to the end of the block being placed — the perpend (vertical) joint must also be 10mm filled. Do not rely on the block sitting into a puddle of mortar to create the joint.
7
Place block, tap level, check the string line Set the block with one firm press and a light rubber mallet tap. The top face of every block should just brush the mason's line stretched from corner to corner. Check level side-to-side; check plumb with a level held vertically.
8
Install rebar per the engineer's plan — not guesswork Vertical rebar (inserted into CHB cores) and horizontal rebar must match the approved structural drawings. Core-fill the rebar cells with concrete (not mortar) — minimum 3,000 psi mix. This is the structural heart of the wall; do not improvise spacing or bar size.
9
Limit to 4–5 courses per day Fresh mortar cannot support the weight of too many courses stacked quickly. Over-building causes courses to push outward (blow-out) while still wet. Let the wall rest overnight before continuing on tall walls.
10
Cure the wall — keep it moist for 7 days Spray the finished wall with water 2–3 times per day for a week, especially in hot/sunny conditions. Cover with burlap or plastic sheeting in intense heat. Proper curing gives mortar and core-fill concrete full strength; skipping it gives you 50–60% of design strength.

❌ Common DIY Mistakes (and How to Avoid Them)

💧
Not wetting blocks before laying Dry CHBs pull water out of mortar in minutes, leaving a crumbly, weak interface. The bond fails — you can pull blocks off by hand after a week. Always pre-wet.
📐
Skipping the level check mid-wall One course 3mm off becomes 15mm off by course 5. A wall that's out of plumb will need to be cut down, or worse — it'll fail inspection. Check level and plumb every single course.
⏱️
Working old mortar past its open time Adding water to stiffened mortar (re-tempering) destroys the chemical bond. A batch that's been sitting over 30 minutes in heat goes in the trash, not on the wall.
🏃
Building too many courses too fast More than 5 courses in a day on a tall wall risks blow-out. The bottom mortar joints haven't set yet and can't hold the weight. Slow down on wall heights over 1.2m.
🔧
Improvising rebar — using different sizes or spacing than specified The structural plan specifies exact rebar diameter and spacing based on seismic zone, wall height, and load. Substituting lighter rebar or wider spacing is a structural deficiency that won't show until a typhoon or earthquake.
🚫
Using mortar to fill rebar cores instead of concrete Rebar cores must be filled with concrete (aggregates + cement + water, properly mixed). Mortar is too weak and will shrink away from the rebar, eliminating the structural connection.

📄 Do You Need a Permit? (By Work Type)

In the Philippines, the requirement for a building permit under PD 1096 (National Building Code) depends on the scope of work — not just whether you're doing it yourself. The property owner is legally responsible regardless of who does the labor.

Work Type Permit Required? Notes
Interior partition wall (non-structural, no floor area change) Usually No Minor interior alteration within an existing permitted structure. Confirm with your LGU — some require a simple renovation permit.
Adding or enclosing a room (increases floor area) Yes — Alteration Permit Any addition that changes the building's gross floor area (GFA) requires an alteration or addition permit from the OBO. File under your original building permit number.
New house or full construction from ground up Yes — Building Permit Full building permit required before breaking ground. Must include engineer/architect-sealed plans. No permit = illegal structure; cannot be sold or mortgaged cleanly.
Perimeter fence / garden wall under 1.2 m high Usually No Varies by LGU. Low fences (under 1.2 m) are generally exempt. Some cities (Manila, QC) require barangay clearance minimum. Always check with your barangay hall first.
Perimeter fence / boundary wall over 1.2 m high Yes — Fence Permit Walls over 1.2 m require a fence/wall permit at the LGU Office of the Building Official. Taller fences (over 2 m) may need structural drawings from a licensed civil engineer.
Demolition of an existing wall Yes — Demolition Permit Required if removing any structural element. Even partial demolition needs an OBO permit. Non-structural partition removal in an existing home may be treated as minor renovation — check with your LGU.
Repair / patching existing CHB walls (no structural change) No Minor repairs and patching (filling cracks, repointing mortar joints, plastering) do not require a permit. You are restoring, not building.
⚠️
Permit tip: Always file the permit under the property owner's name — not the contractor's. The permit is attached to the land title. A structure built without a permit cannot easily get a Certificate of Occupancy, and this will create problems when selling or using the property as collateral.

🔍 Inspections You Must Pass (If You're Owner-Builder)

On a permitted project, the LGU Office of the Building Official (OBO) will conduct site inspections at key construction stages. As the owner-builder, you are responsible for calling in each inspection — the OBO will not schedule these automatically. Failing to call for inspections before covering work is a common cause of permit violations.

1
Excavation / Footing Inspection — before pouring any concrete The OBO inspector checks: excavation depth, width, bearing soil condition, rebar cage dimensions and cover. Do not pour the footings before this inspection is done and recorded. If you pour over un-inspected footings, you may be required to demolish and rebuild.
2
Foundation / Grade Beam Inspection — before backfilling Checks: tie beam dimensions, rebar placement, dowel bars for columns. Backfilling over un-inspected grade beams is the same problem — stop work, call the inspector.
3
Structural Frame Inspection — before closing formwork Covers column and beam rebar, column splices, formwork dimensions, and concrete mix. The inspector may check slump test records or ask for pour documentation. This is the stage where illegal deviations from approved structural plans are most commonly flagged.
4
CHB Wall / Masonry Inspection — after rebar placement, before core-fill The inspector checks: block size matches approved plans (4" vs 6"), rebar size and spacing in cores, mortar joint quality, wall plumb and alignment. Core-fill concrete must not be poured until this inspection is cleared. If you filled the cores before the inspector visited, you've created an unverifiable structure.
5
Electrical Rough-In Inspection — before covering walls The electrical inspector (or OBO with electrical plans) checks: wire gauge, conduit type, panel board rough-in, circuit breaker sizing. Do not plaster over electrical rough-in before this pass. A failed electrical rough-in means opening walls after plastering.
6
Plumbing / Sanitary Rough-In Inspection — before covering pipes Checks drain slope, vent pipe installation, cleanout locations, septic tank size and design. Required before slab and floor tile work covers the drain runs. Rework behind tile is expensive.
7
Final Inspection + Certificate of Occupancy Done when construction is complete. The OBO checks compliance of the finished structure against the approved plans. BFP (Bureau of Fire Protection) conducts a separate fire safety inspection. Both must be cleared before you legally occupy the building. The Certificate of Occupancy is what you present to MERALCO and the water utility to get permanent connections.
📞
How to call for an inspection: Visit or call your LGU's Office of the Building Official (OBO) with your building permit number. Some LGUs now accept inspection requests online or via Messenger. Budget 3–7 working days lead time for the inspector to arrive. Keep a site logbook — inspectors will sign and note their findings.

🔑 DIY-Safe vs. Requires a Licensed Professional

✅ Generally DIY-Possible
  • Laying non-structural interior partition walls (dividers between rooms)
  • Garden walls, perimeter fence walls under 1.2m
  • Patching or repointing existing CHB walls
  • Plastering and skimcoating existing walls
  • Installing window and door frames in pre-formed openings
  • Curing, painting, and finishing after structural work is done
⚠️ Needs a Licensed Professional
  • Any load-bearing CHB wall on a permitted project — rebar placement requires engineer sign-off
  • Stiffener columns and lintel beams — require formwork, RC mix design, and structural inspection
  • Foundation and grade beams — never lay CHB on unapproved footings
  • Electrical rough-in — requires PEC-licensed electrician; fire hazard if done wrong
  • Anything above 3m height — requires scaffolding with fall protection and engineering oversight
  • Walls in seismic Zone 4 or wind-exposure Class C/D — NSCP requires engineering design, not rule-of-thumb
💡 Bottom line on DIY: You can save 20–35% of labor cost by laying partition walls yourself. On a 4-bedroom house, that might be ₱30,000–₱80,000 in savings. But the structural walls, columns, and beams are not the place to cut corners. Hire the panday for the structural work; take over on the interior partitions once the frame is approved.

⚠️ Estimating Tool — Not a Structural Engineering Service

This calculator provides ballpark material quantity estimates based on standard Philippine construction rules of thumb, NSCP structural guidelines, and common panday practice. It is designed for planning and budgeting purposes only.

These estimates do not replace a formal Bill of Quantities (BOQ) prepared by a licensed civil or structural engineer. Actual quantities will vary based on wall configuration, block quality, mortar application method, site conditions, and contractor technique. Always get a professional BOQ before purchasing materials for a major build.

BuildCostPH is a free planning tool. We are not licensed contractors, engineers, or architects. Always consult a registered civil engineer for any structural wall design.