Estimating guides & standards references
Practical guides on Philippine construction estimating — PNS/DPWH standards, BOQ structure, and the formulas behind ConstructPro's calculators, written for estimators and contractors.
Fire Suppression: How Sprinkler Head Count Actually Gets Calculated
NFPA 13 coverage-area limits by hazard class, and why a "light hazard" office and a warehouse need very different head counts for the same floor area.
4 min read · Fire Suppression HVACHVAC: How Cooling Load (Tonnage) Gets Estimated From Floor Area
Why a restaurant needs nearly twice the cooling capacity per square meter that a well-insulated office does, and the m²-per-ton figures behind that difference.
4 min read · HVAC CarpentryCarpentry Take-Offs: Why Board-Feet Depend on Spacing, Not Just Size
The Fajardo area-method factors behind stud and joist board-foot counts, and why tightening spacing from 60×60 to 30×30 cm nearly quadruples the lumber.
4 min read · Carpentry Site WorksSite Works: Asphalt Surface Treatment and Curb Concrete, By the Numbers
Bitumen and aggregate coverage rates for bituminous surface treatment, and the concrete volume a lineal meter of curb actually needs.
4 min read · Site Works EarthworkEarthwork: Bank, Loose, and Compacted — Why the Same Soil Has Three Different Volumes
Swell factors for excavated soil and fill-additional percentages for compacted fill, and why hauling estimates that skip this step come up short.
4 min read · Earthwork Elevators & LiftsElevators & Lifts: Why Pricing Is Structured Per Stop, Not Per Floor Height
Why elevator estimates multiply units by stops rather than by building height, and what the pit & shaft works line item actually covers.
4 min read · Elevators & Lifts