Work out change order impact instantly with clear inputs, formula shown and shareable results.
A change order carries both a direct cost and a time impact, and the time impact brings prolongation cost — site overheads, supervision and plant standing time — which is often claimed separately. Estimating it at around 15% of the pro-rata contract value for the extension period gives an early exposure indication.
Revised value
Revised = Original contract value + Change order value
Implied prolongation
Prolongation = Original value / Duration x Extension weeks x 15%
Indicative estimate only. Fees, entitlements, limits and formulas vary by jurisdiction, statute, policy wording and the facts of the case. This is not legal, tax, insurance or financial advice — confirm with a qualified professional or the relevant authority.
Yes, always. Agreeing cost while leaving the time impact open is the single most common route to a later prolongation claim.
Beyond about 15-20% of original value the contract has effectively changed in character, which can raise procurement compliance questions.