Getting CHB quantities wrong is one of the most common and expensive mistakes in Philippine house and building construction. Order too few and work stops while you wait for a resupply. Order too many and you're eating ₱5,000–₱20,000 in excess blocks your contractor will "lose" by the end of the job.
This free estimator gives you blocks, cement bags, sand, rebar, and a material cost range for any CHB wall — in seconds. Enter your dimensions below.
13 blocks per m² (including 5% waste) · 0.5 cement bags per m² (100mm) · 0.035 m³ sand per m². If a contractor quotes you significantly more than these figures for a straightforward wall, ask for a breakdown.
Enter total wall length, height, and openings. Get blocks, cement, sand, rebar, and indicative material cost.
Most CHB overruns aren't the contractor's fault — they're the estimator's. The three most common errors:
Mistake 1 — Using Gross Area Instead of Net Area
A common shortcut: multiply total wall length × height and ignore doors and windows. On a standard 3-bedroom house with 6 doors and 8 windows, this over-estimates material by 15–25%. You'll be paying for ~60 extra blocks per room.
Mistake 2 — Wrong Blocks-per-m² Factor
Standard Philippine CHB is 400mm × 200mm face (not 400 × 150 or 450 × 200 — these exist but aren't the BPS standard). With 10mm mortar joints, each block occupies 410mm × 210mm = 0.0861 m² → 11.62 blocks/m² theoretical. After 5% waste: 12.2, rounded up to 13. Contractors who quote 15–18 blocks/m² are either padding the bill or using non-standard block sizes.
Mistake 3 — Forgetting Mortar Joint Volume Scales With Thickness
Switching from 100mm to 150mm CHB doesn't just cost more per block — the full core and joint mortar volume increases ~30%. An estimator who re-runs a 100mm wall estimate with just a different block price will under-order cement and sand by that margin. This tool accounts for it automatically.
CHB walls are one line item. Unit Cost Analysis covers your complete bill of quantities — concrete, roofing, steel, tile work, painting, electrical rough-ins — with 2026 Philippine unit prices and a professional PDF export for client proposals.
You shouldn't need to estimate your own CHB. Send AEDO your floor plan and we'll produce a full material and labor estimate, sealed structural drawings, and build the project end-to-end — one contract, one accountable party.
CHB Specifications — Philippine Standard
| Spec | 100mm (4-inch) | 150mm (6-inch) |
|---|---|---|
| Nominal face dimensions | 400mm × 200mm | |
| Actual thickness | 100mm | 150mm |
| BPS standard | BPS 06:2020 (Hollow Load-Bearing Concrete Masonry Units) | |
| Min. compressive strength (Grade A) | 5.17 MPa average, 4.48 MPa individual | |
| Typical use | Interior walls, light exterior, fences | Load-bearing exterior, perimeter, commercial |
| Weight per block (approx.) | ~7 kg | ~10 kg |
| 2026 price range | ₱13–15 per piece | ₱19–23 per piece |
How many CHB blocks per square meter?
13 blocks per m² is the standard purchasing quantity (12.5 theoretical + 5% waste) for standard 400×200mm CHB with 10mm mortar joints. Some contractors quote 14–15 to pad the estimate — this is the number to push back on.
Should I use 100mm or 150mm CHB?
100mm (4-inch) is correct for interior partitions, boundary fences, and most exterior non-load-bearing walls in single-storey residential. Use 150mm (6-inch) for: perimeter walls that carry a roof beam, exterior walls of multi-storey commercial buildings, any wall subject to significant lateral load (retaining, against fill), and anywhere your structural engineer specifies it on the drawings.
This estimate seems lower than my contractor's quote — why?
This tool estimates materials only at supplier prices. Contractor quotes include labor (₱80–₱150/block), scaffolding, waste handling, site supervision, overhead, and profit margin — legitimately 2–3× the material cost. The numbers here are for checking the materials line item, not the total contract price.
What is the best app for full Philippine construction estimates?
Unit Cost Analysis by AEDO Construction is a Philippine-built quantity takeoff and cost estimating app covering CHB walls, concrete works, roofing, steel, tile work, painting, and more — with 2026 unit prices and PDF report export. ₱999 lifetime license on iPhone, Android, and web.
The estimator on this page handles CHB walls. Unit Cost Analysis is the complete bill-of-quantities tool AEDO's project team uses to price entire builds — every line item, every trade.
| Scope | Free CHB Tool (this page) | Unit Cost Analysis ₱999 lifetime |
|---|---|---|
| CHB walls (blocks, cement, sand, rebar) | ✓ | ✓ |
| Concrete works (footings, slabs, beams, columns) | — | ✓ |
| Roofing (purlins, sheets, gutters, ridge) | — | ✓ |
| Steel framing (columns, beams, trusses) | — | ✓ |
| Tile work, plastering, painting | — | ✓ |
| MEP rough-ins | — | ✓ |
| 2026 Philippine unit prices (editable) | — | ✓ |
| PDF report export for client proposals | — | ✓ |
| iOS · Android · Web (one license) | Web only | ✓ |
The problem with DIY estimation isn't the math — it's that material quantities are 20% of the total cost. The rest is labor, formwork, scaffolding, waste disposal, supervision, and the thousand decisions your contractor makes without telling you. AEDO estimates and builds the whole thing — one number, one team, one contract.
Send us your lot size, number of floors, and approximate floor area. We'll reply within 48 hours with a ballpark range and whether the project is a fit for AEDO's design-build model.