Estimator playbook

Manpower, manning & the estimating rules that hold up in the field

Field-tested tips from senior estimators. Use them as the sanity check before every number leaves your desk.

Manning & manpower

01 · Crew

Crew mix, not headcount

Price a realistic ratio — 1 lead / 2 journeymen / 1 helper beats 4 generic bodies. Blend the burdened rate, not the top of scale.

Productive hours ≠ clock hours

Assume 6.5 productive hours per 8-hour shift. Bake in mobilization, breaks, cleanup, and end-of-day tool time before you divide the scope.

Stack by constraint

Manpower is capped by access, not by budget. Two-story interior? One trade per floor. Tight mechanical room? One body in, one staging.

Overtime is a multiplier, not a schedule fix

After 50 hrs/week productivity drops ~15%. Price OT at 1.5× wage AND 1.15× hours to hit the same output.

Estimating procedure

02 · Process
01

Walk the scope before the takeoff

Scan the space end-to-end first. Note access, ceiling height, existing conditions, and demo. Half of missed cost lives here, not in the plans.

02

Quantify, then qualify

Get quantities off the model or scan first. Only then apply waste factors, crew productivity, and site-specific difficulty multipliers.

03

Price the risk line

Every bid gets a contingency row you can defend: unknowns (5–10%), schedule risk (3–5%), escalation (2–4%). Never hide it in unit prices.

04

Review with the field

Before it ships, the foreman who will build it reviews crew size, sequencing, and duration. If they flinch, re-price it.

Rules of thumb

03 · Judgment

Unit prices lie at the edges

Historical $/sf holds in the middle 60% of jobs. Small jobs eat mobilization; mega jobs get productivity gains. Adjust both tails.

One assumption sheet, always

Every bid ships with a written assumptions & exclusions page. It's the cheapest change-order protection you'll ever write.

Bid the scope, not the drawing

Drawings miss things. Read specs, RFIs, and addenda in that order and reconcile against the plan set before you total.

Flag the fatal three

Access, power, and water. If any one is unclear on walk-through, that's a qualified bid — not a hard number.

Quick-reference factors

Cheat sheet
Productive hours
6.5 / 8 hr shift
Applies to most trades on occupied sites
OT productivity loss
~15% after 50 hr/wk
Compounds week over week
Waste factor
5–10% typical
Frame lumber 10%, drywall 8%, tile 15%
Small-job mobilization
+8–12% under $25k
Truck rolls, minimums, PM overhead
Contingency (hard bid)
5–10%
Higher on renovation & unknowns
Escalation (12+ mo)
3–5% / year
Track by CSI division, not blanket
Foreman ratio
1 : 6–8 crew
Drops to 1:4 on complex MEP
Access / floor limit
1 trade per floor
Unless stacked shifts are priced in

Factors are industry starting points — always calibrate against your own historical job costs.