Resource Basis of Estimates
A completed example demonstrating how to document the approach, assumptions, and confidence levels for a project's resource estimates.
§1 Approach
Resource estimates were developed bottom-up from the Activity List. For each activity, the estimating team identified the type, quantity, and skill level of human resources required, plus any physical resources (equipment, materials, supplies, services, facilities). Estimates were validated against analogous prior projects and refined using expert judgement from the PM and team leads.
Contents ↑§2 Estimating Methods Used
- Bottom-up: Each activity's resource needs estimated individually, then aggregated to the work-package and project level. Used as the primary method.
- Analogous: Resource counts validated against two prior projects (brand refresh 2024; marketing-site refresh 2023). Showed similar 4-person core team and 1 vendor adequate.
- Parametric: Used for content production (hours-per-page, hours-per-case-study) and imagery ($/image × number of images).
- Expert judgement: Team leads (Bob, Bill, Christine) consulted on skill-level requirements for their respective domains.
§3 Source of Information
- Activity List and Activity Attributes (effort hours).
- Resource Management Plan (team roles and skill levels).
- Firm's FY2026 internal blended-rate schedule.
- Approved vendor list (frontend contractor, WCAG audit vendors).
- Two analogous prior internal projects.
§4 Assumptions
- Internal labour billed at fully-loaded firm-standard rates.
- Core team allocated at planned percentages through project close (PM 50%, Bob 75% during build, Bill 75% during design, Christine 60% throughout).
- Frontend contractor available within 2 weeks of SOW signing.
- No travel is required; all consultants engage remotely.
- Firm-approved cloud and CMS providers offer the capacity needed.
§5 Constraints
- Total budget capped at $150,000 (charter).
- Core team fixed at PM + 3 internal roles plus 1 frontend contractor; functional managers must approve any additions.
- Vendor selections constrained to firm's approved supplier list.
- WCAG 2.1 AA audit requires an accredited 3rd-party firm, which limits the supplier pool.
§6 Range & Confidence
- Human resources: Confidence is High; estimates are based on a fixed core team with confirmed availability. Range ±10%.
- Vendor labour (frontend contractor): Medium confidence; SOW preliminary. Range ±15%.
- Physical resources: Medium-High confidence; vendor SOWs and licensing prices quoted as of May 2026. Range ±10%.
- Photography & imagery: Lower confidence; consultant participation rate unknown. Range ±25%.
§7 Risks & Reserves
Resource-related risks tracked in the Risk Register: consultant unresponsiveness on bio collection (R-04 risk to scope); frontend contractor capacity; vendor delivery delays; team-member illness or attrition. Contingency reserve ($15K) covers known-unknowns; management reserve ($7.5K) covers unknown-unknowns.
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