BIZOMAT Tools · Decide
Change Impact Assessment
How disruptive is this proposed change?
Assesses a proposed change by its added cost, schedule effect, risk and quality impact against the benefit it brings.
Open the calculatorRuns in your browser. No account needed.
How this tool works
Inputs, units and where to find them
| Input | Unit | Typical source |
|---|---|---|
| Additional cost | $ | Estimate of the change’s added cost |
| Current project or process value | $ | Current approved budget or process value |
| Schedule impact | days | Schedule extension caused by the change |
| Remaining schedule | days | Remaining approved schedule |
| Risk increase | 1–5 score | Rating of risk increase (1 small, 5 large) |
| Quality impact | 1–5 score | Rating of quality or compliance impact (1 small, 5 large) |
| Expected benefit | $ | Benefit estimate in the change request |
What each input means
Open an input to see what it is, its units, the worked example and the common mistakes, with a small diagram.
What this means: Additional cost
- What it is
- The extra money the proposed change adds to the project or process, from the estimate in the change request.
- Units and format
- Enter a number in $: an amount of money; use one currency for every money input. The form accepts $0 or more.
- Example
- The form opens with $5000 as a worked example. It is an illustration, not a recommended value: replace it with your own figure.
- Effect on the result
- Turned into a percentage of the current value; each 1 % adds 0.25 points to the impact score.
- Get it right
- Include rework, extra materials and added labour, not only the obvious purchase.
What this means: Current project or process value
- What it is
- The current approved budget of the project, or the value of the process being changed. The added cost is judged against it.
- Units and format
- Enter a number in $: an amount of money; use one currency for every money input. The form accepts $1 or more.
- Example
- The form opens with $50000 as a worked example. It is an illustration, not a recommended value: replace it with your own figure.
- Effect on the result
- A larger base makes the same added cost a smaller percentage and lowers the impact score.
- Get it right
- Use the approved budget, not the amount spent so far.
What this means: Schedule impact
- What it is
- How many days the change would push out the finish date, from the revised schedule.
- Units and format
- Enter a number in days: days. The form accepts 0 days or more.
- Example
- The form opens with 5 days as a worked example. It is an illustration, not a recommended value: replace it with your own figure.
- Effect on the result
- Turned into a percentage of the remaining schedule; each 1 % adds 0.25 points to the impact score.
- Get it right
- Count only the delay to the end date; work that runs in parallel without moving the finish adds no delay.
What this means: Remaining schedule
- What it is
- The number of days left in the approved schedule before the change. The delay is measured as a share of this.
- Units and format
- Enter a number in days: days. The form accepts 1 days or more.
- Example
- The form opens with 60 days as a worked example. It is an illustration, not a recommended value: replace it with your own figure.
- Effect on the result
- A longer remaining schedule makes the same delay a smaller percentage.
- Get it right
- Use days remaining, not the original total duration.
What this means: Risk increase
- What it is
- How much the change raises delivery, safety or technical risk, rated 1 (small increase) to 5 (large increase).
- Units and format
- Move the slider to a score from 1 (low) to 5 (high).
- Example
- The form opens with 3 as a worked example. It is an illustration, not a recommended value: replace it with your own figure.
- Effect on the result
- Each point adds 5 points to the impact score.
- Get it right
- Judge the added risk from the change itself, not the project’s overall risk level.
What this means: Quality impact
- What it is
- How much the change could affect product quality, specification or compliance, rated 1 (small) to 5 (large).
- Units and format
- Move the slider to a score from 1 (low) to 5 (high).
- Example
- The form opens with 3 as a worked example. It is an illustration, not a recommended value: replace it with your own figure.
- Effect on the result
- Each point adds 5 points to the impact score.
- Get it right
- A rating of 4 or more calls for quality or engineering sign-off before approval.
What this means: Expected benefit
- What it is
- The money the change is expected to save or earn, as stated in the change request. It is compared with the added cost.
- Units and format
- Enter a number in $: an amount of money; use one currency for every money input. The form accepts $0 or more.
- Example
- The form opens with $10000 as a worked example. It is an illustration, not a recommended value: replace it with your own figure.
- Effect on the result
- Does not change the impact score; it sets the benefit-minus-cost result and its check.
- Get it right
- Use the same period for benefit and cost, for example both over the life of the project.
Method and formulas
- Impact = 0.25 × cost increase % + 0.25 × schedule increase % + 25 × risk ÷ 5 + 25 × quality ÷ 5, limited to 0–100
- LOW below 30, MODERATE 30–59, HIGH 60 or more
Limitations
- Percentages above 100% saturate the score
- Fixed weights
- Does not check contract or authority to approve
Typical uses
- Change requests on projects
- Engineering change proposals
- Process changes that affect cost or delivery
Who it is for
- Project managers
- Engineering change boards
- Quality managers
What you get
- LOW, MODERATE or HIGH impact
- Impact score out of 100
- Benefit minus added cost
Interpreting the result
- High quality impact needs engineering or quality sign-off whatever the score
- Approve only when the benefit justifies cost, schedule and risk together
References
- PMI, A Guide to the Project Management Body of Knowledge (PMBOK Guide), integrated change control
BIZOMAT tools are screening and decision-support utilities. Verify important financial, engineering, safety, legal or operational decisions using appropriate professional standards and your organisation’s approved data.