Variations, Delays and Extensions of Time

Written by Richard O'Shea, Solicitor TEP · Mary Molloy Solicitors, established 1981 · Last reviewed 21 August 2026

Variations: no change until it's priced

Almost every domestic building dispute we've litigated features unpriced extras: work was done, the bill arrived, and the homeowner "never agreed to that". The cure is procedural, not moral — a variations clause that says no change is built until it is described, priced and confirmed in writing (a text or email exchange is fine if the clause says so), with an agreed effect on the completion date. One page. It protects the builder's margin and the homeowner's budget equally, which is why both sides should insist on it.

Who prices the variation?

On architect-administered RIAI contracts, the architect values variations under the contract machinery. On plain contracts, fix the method in advance: quoted lump sums for defined changes, or agreed rates for labour and materials plus a stated percentage. "Reasonable cost" is an argument, not a method.

Delay: three kinds, three answers

• Builder-caused delay — the employer's remedy is liquidated damages: a fixed, realistic weekly sum for late completion, written into the contract from day one
• Employer-caused delay — late decisions, late access, late selections: the builder gets an extension of time and, where the contract provides, the associated costs
• Neutral events — weather, strikes, supply chain: allocated by the extension-of-time clause; typically the builder gets time but not money

Extensions of time: notice is everything

Extension clauses almost always require the builder to notify the delay event promptly, often within a fixed number of days, sometimes as a condition of any entitlement. Builders: diary it, notify in writing every time, even when relations are good. Employers: respond in writing. The party with the paper trail wins the time argument — and time arguments are money arguments, because they decide who pays liquidated damages and prolongation costs.