The 4 Golden Rules & Requirements for a Successful Claim on Variations.
The 4 Golden Rules & Requirements of a Variation Claim
— With UK & Malaysian Case Illustrations —
Introduction
Variation claims are among the most common causes of construction disputes. Across all major standard forms — FIDIC, PAM, JKR, and CIDB — success in such claims turns on four key questions:
(1) What’s the change of scope? (2) Was the variation properly instructed and notified? (3) Did the right person issue the instruction? (4) How should the varied works be valued?
All four are governed by a single unifying legal doctrine — the Four-Corners Rule — under which the contract must be construed strictly from the written terms within its “four corners,” not from oral or implied agreements.
This rule was reaffirmed by the Federal Court of Malaysia in KDSB Sdn Bhd v Port Klang Authority (2025) under Evidence Act 1950, Sections 91–92.
Key takeaway: Every variation claim lives or dies within the written contract — not beyond it.
Rule Number 1 : What’s the Change of Scope?
Principle: The contractor must prove that the alleged varied work lies outside the original scope of the contract. i.e. The 4 Corner Rule Above.
This is the first and most essential step before any entitlement arises.
UK Cases
In Gaymark Investments Pty Ltd v Walter Construction Group Ltd (1999) and Henry Boot Construction Ltd v Alstom Combined Cycles Ltd [2005] EWCA Civ 814, the courts clarified that a variation exists only when the new work falls clearly beyond the original contractual obligations. The valuation of such works must first refer to the contract rates before any departure to “fair valuation.”
Lesson from UK: If the work is part of your original obligation — even if harder or costlier — it is not a variation.
Malaysian Cases
- Thye Hin Enterprise Sdn Bhd v Daimler Chrysler Malaysia Sdn Bhd (Court of Appeal) — The Court held that the contractor bore the burden of proving that “extra works” were outside the defined contractual scope.
- Malaysian Refining Co v Sumatec Engineering (Malaysia) — The High Court reaffirmed that additional works must be shown to be outside the scope expressly or impliedly covered by the contract before payment is due.
Lesson for Malaysia: Establish a clear “scope delta” — compare the original drawings, BOQ, and specifications against the revised works. Without this contrast, no entitlement arises.
Rule Number 2 : Was the Variation Properly Instructed and Notified?
Principle: Even a genuine variation may fail if the contractor does not comply with procedural requirements — particularly the need for written instructions and timely notice. Most standard forms make notice a condition precedent to entitlement.
UK Cases
In Balfour Beatty Construction Ltd v Lambeth LBC (2002), the contractor executed additional works on verbal direction from the employer’s representative. The court held that, because the contract required written instructions, the oral directive was invalid, and the contractor was not entitled to payment.
Lesson from UK: Verbal approvals are not enforceable when the contract demands written instructions.
Malaysian Cases
- Sunissa Sdn Bhd v Kerajaan Malaysia & Anor [2020] MLJU 283 (High Court) — The court held that failure to comply with the written notice requirements under the PWD form barred part of the contractor’s claim.
- JKR Malaysia & Anor v Sunissa Sdn Bhd [2022] 5 MLJ 705 (Court of Appeal) — The appellate court confirmed that notice provisions were valid and binding as conditions precedent.
- Malaysian commentary further aligns this with Evidence Act 1950 s 91, which confines proof to the written document.
Lesson for Malaysia: Always issue notice and variation requests in writing within the time and format stipulated. Courts will not excuse non-compliance.
Rule No 3 : Did the Right Person Instruct the Variation?
Principle: A variation is valid only if issued by the contractually authorised person — usually the Architect, Engineer, or Superintendent. Instructions from others are ineffective unless later confirmed in writing by the authorised person.
UK Cases
In F.G. Minter Ltd v Welsh Health Technical Services Organisation [1980] 13 BLR 1, the court ruled that directions given by the employer’s clerk — who lacked authority — were not binding. Only the engineer’s written instructions under the contract were valid.
Lesson from UK: Authority is as crucial as content — instructions from unauthorised persons are void.
Malaysian Cases
- Under PAM 2006/2018, only the Architect’s written instructions (AIs) may constitute valid variations. Site memos or informal directives are not binding unless ratified by the Architect or Employer.
- Malaysian practice echoes the Minter principle: unauthorised instructions fall outside the four corners of the contract and therefore confer no entitlement.
- Local arbitral awards and High Court commentary treat ratification or written confirmation as necessary to validate any such directions.
Lesson for Malaysia: Always confirm instructions in writing from the authorised contract administrator before executing work.
Rule No 4 : How Should the Varied Works Be Valued?
Principle: Once entitlement to a variation is established, the valuation must follow the contract’s hierarchy:
- Apply existing contract rates.
- Adjust those rates if conditions differ.
- Resort to a fair and reasonable valuation only if no comparable rate exists.
UK Cases
In Henry Boot Construction Ltd v Alstom Combined Cycles Ltd [2005] EWCA Civ 814, the Court of Appeal held that where applicable rates exist in the contract, they must be used. Departure to new or “fair” rates is allowed only where no comparable item or condition exists.
Lesson from UK: Apply the contract’s valuation mechanism before introducing new rates.
Malaysian Cases