Variation Orders: Written Instructions, Pricing Extra Work and Consumer Rights Act Compliance

Summary

Variation orders are one of the most common sources of dispute in construction. A tradesperson is asked to do extra work on site — the client says "while you're here, can you also…" — and if that conversation is not captured in writing before work begins, both parties are exposed. The tradesperson may not get paid, or may get paid less than the work is worth. The client may dispute the price entirely.

The Consumer Rights Act 2015 and the Housing Grants, Construction and Regeneration Act 1996 (the Construction Act) together define the legal framework for variations on domestic and commercial projects. For domestic clients, oral instructions can create binding obligations under Section 50 of the CRA 2015, but written confirmation is still the best protection. For commercial contracts, the Construction Act requires clear payment mechanisms — and variations feed into the final account.

A variation order does not need to be a complex document. A brief written description of the additional scope, the agreed price, any impact on programme, and both parties' agreement (even by reply email) is sufficient for most residential and small commercial jobs. The key discipline is doing it before the work starts, not after.

Key Facts

• Consumer Rights Act 2015 Section 50 — oral representations made by a trader before or during a contract are binding terms, even if not written into the contract
• Written confirmation method — email, text message, WhatsApp, or signed paper form are all valid; no specific form is prescribed
• Timing — confirm variations in writing BEFORE starting the additional work
• JCT Minor Works 2016 Clause 3.6 — the contract administrator or employer may instruct variations; the contractor must comply and is entitled to fair payment
• Quantum meruit — if there is no agreed variation price, a court may award a "reasonable sum" for work done — typically calculated from labour rate, time, and materials with a reasonable margin
• Unsigned variation order risk — if a client refuses to sign, proceed on the basis of written confirmation (their email or text accepting scope) rather than their signature
• CDM 2015 — significant scope changes may require updating the Construction Phase Plan and notifying the Principal Designer
• Programme impact — always state whether the variation affects the completion date; silence may be taken as acceptance of no delay
• Oral instruction procedure — confirm any oral instruction in writing within 24 hours; ask the client to acknowledge receipt
• Scope creep — a series of small variations that collectively represent significant additional cost and time must still be formally managed
• Dispute risk — undocumented variations are the most common cause of payment disputes and adjudication claims in small works
• Day rate fallback — where price cannot be agreed upfront, confirm a day rate in writing before starting; this is better than proceeding without any agreed rate
• Variations and retention — if the main contract includes retention, variations are typically subject to the same retention percentage unless otherwise agreed
• Price escalation — for long-running projects, state whether variation prices are fixed or subject to material cost fluctuation

Quick Reference Table

Detailed Guidance

What Counts as a Variation

A variation is any change to the agreed contract scope — additions, omissions, or substitutions. Common examples on residential jobs include:

• Discovering unexpected rot, damp, or structural defects during works that require additional remediation
• Client requesting an upgrade in specification (e.g., better tiles, additional sockets, upgraded boiler model)
• Client requesting additional rooms to be included in a painting or flooring job
• Reduction in scope (client decides not to install a new window mid-job)
• Changes in access, working hours, or programme that affect cost

The crucial distinction is between a variation (which the contractor is entitled to be paid for) and a contractor's obligation to complete their original scope correctly (which is not extra work). If a wall needs replastering because the plasterer applied it wrong the first time, that is remedial work — not a variation.

Consumer Rights Act 2015 and Domestic Contracts

For contracts with domestic clients (consumers), the Consumer Rights Act 2015 applies rather than the standard commercial construction law framework. Key provisions:

Section 50 — any oral statement made by the trader about the service (including scope, price, and programme) is binding as a contract term unless the trader clearly states it is not. This means that if a tradesperson verbally promises to include extra work at no additional charge, that promise may be enforceable even without a written variation.

Section 49 — the service must be performed with reasonable care and skill. This does not create an obligation to do additional work not in the contract, but it does mean that advice given on site (e.g., "that wall looks fine") may create liability if it is later shown to be incorrect.

Practical implication for tradespeople: Always follow up verbal discussions with a written summary. A WhatsApp message saying "Following our conversation today, I'll also install the additional socket in the bedroom for £95 including materials — let me know if that's agreed" is sufficient to create a binding variation order.

Using squote: Variation orders raised in squote are sent to the customer by email as a dated PDF and stored permanently alongside the original quote — timestamped, on record, and no WhatsApp screenshots required.

Written Confirmation: What It Must Include

A variation order — whether formal or informal — should capture:

1. Job reference — refer to the original quote or contract number
2. Date — when the instruction was given and when the work will be done
3. Description of additional work — specific enough to be unambiguous
4. Agreed price — fixed price, or day rate × estimated days, or materials cost + labour
5. Materials — who supplies them and at what cost (if not included in price)
6. Programme impact — does this variation change the completion date, and if so by how much
7. Signature or written acknowledgement — both parties' agreement (a reply email counts)

A variation order does not need to be on a formal printed form for small domestic jobs. The discipline matters more than the format.

Template Variation Order Wording

The following can be adapted for email, text, or a simple printed form:

Variation Order — [Your Company Name]

Job Reference: [Original Quote No.] Date: [Date] Property: [Address]

Description of Additional Work: [Clear description of what is to be done, including location and specification]

Agreed Price (inc. VAT): £[amount] (Or: Day rate of £[rate]/day + materials at cost + [X]% markup)

Effect on Programme: [State: "no change to completion date" OR "completion date extended by X days to [new date]"]

This variation is in addition to the original contract dated [date] for £[original price].

Agreed by client: [Name / email reply / signature]

JCT Minor Works 2016 and Formal Contract Variations

Where JCT Minor Works 2016 is in use (common on small-to-medium domestic extensions and commercial fit-outs), Clause 3.6 gives the Employer (or Contract Administrator acting on their behalf) authority to instruct variations. The contractor must comply with a variation instruction and is entitled to payment.

Key points under JCT MW 2016:

• The contractor must not carry out a variation without written instruction — oral instructions should be confirmed in writing by either party within 7 days
• The value of variations is usually agreed by reference to the contract rates, or by daywork if no applicable rates exist
• Daywork must be submitted and agreed promptly (usually within the next certification period) — late daywork claims may be rejected
• If the contractor considers a variation instruction will affect the completion date, they must notify the Employer/CA promptly — failure to notify may lose the right to an extension of time

CDM 2015 Implications for Variations

For projects that are CDM-notifiable (lasting more than 30 working days with more than 20 workers simultaneously, or exceeding 500 person-days), significant variations may trigger obligations under CDM 2015:

• The Construction Phase Plan must be updated to reflect new scope, new risks, or new activities
• The Principal Designer should be notified of significant changes to the design
• If the variation introduces a new notifiable hazard (e.g., working at height not previously planned, or excavation near underground services), a method statement or risk assessment must be prepared before work starts

For the majority of residential works, CDM notifications are not triggered, but the duty to manage health and safety risks applies regardless.

Dealing with Scope Creep

Scope creep is a series of small additions that cumulatively represent a significant increase in cost and time. The risk is that individually each change seems trivial ("just one more socket"), but collectively they add several days and hundreds of pounds to the job.

Prevention checklist:

• Issue a variation order for every change, however small
• Keep a running variation log — job reference, date, description, agreed price, signed
• At key project milestones (end of each week, or at each stage payment), issue a variation account showing all agreed variations to date
• At final account stage, the variation account forms part of the invoice — not a surprise addition

Pricing a Variation: Options

Fixed price — best for well-defined additional work (e.g., install one additional radiator). State total price including materials and labour.

Day rate — appropriate where scope is uncertain or the work is exploratory (e.g., opening up a wall to investigate). State the day rate and estimated number of days.

Cost plus margin — used for materials-heavy variations where the cost is unknown at instruction stage. Agree the markup percentage upfront (typically 10–20% on materials).

Provisional sum — include an allowance in the variation for work that cannot be fully scoped yet. Adjust to actual at final account.

Frequently Asked Questions

What if the client refuses to sign a variation order?

Written confirmation does not require a physical signature. A reply email from the client acknowledging and accepting the variation ("yes, please go ahead") is sufficient. If the client provides no written acknowledgement at all, send the variation order by email and keep a record that it was delivered. A quantum meruit claim — for the reasonable value of work done — remains available even without a signed agreement, but it is a higher-risk route that may require court proceedings.

Can I refuse to carry out a variation instruction?

On a JCT contract, you must carry out a valid variation instruction, but you are entitled to fair payment. On a simple domestic quote contract, you can negotiate the scope and price before agreeing to proceed. You should not start additional work at the same rate as the original contract unless specifically agreed — silence on price is not acceptance.

Does a variation order affect my defects liability period?

Typically, variations are subject to the same defects period as the main contract works. Any defects in the variation work should be remedied within the same period. If the variation introduces a different specification (e.g., a different material), ensure the defects obligation for that variation is clear.

What is the difference between a variation and a provisional sum?

A provisional sum is an allowance included in the original contract for work that could not be fully specified at tender stage (e.g., "allow £2,000 for kitchen electrical works, to be confirmed"). It is part of the original contract, not a variation. A variation is a change to what was originally specified — whether an addition, omission, or substitution.

Regulations & Standards

• Consumer Rights Act 2015, Section 50 — oral pre-contractual and contractual representations are binding

• Housing Grants, Construction and Regeneration Act 1996 — payment mechanisms for construction contracts; applies to commercial contracts

• JCT Minor Works Building Contract 2016, Clause 3.6 — variation instruction and valuation procedure

• CDM 2015 (Construction Design and Management Regulations) — [verify specific regulation numbers for scope change obligations]

• Late Payment of Commercial Debts (Interest) Act 1998 — applies to commercial variation invoices if unpaid beyond agreed terms

• JCT Minor Works Building Contract 2016 — Standard form contract for small works

• Consumer Rights Act 2015 — Section 50, pre-contractual representations

• Citizen's Advice — Contracts and the Law — Plain-language guide to contract disputes

• RICS — Variations and Claims in Construction — Professional guidance on variation valuation

• HSE — CDM 2015 Guidance — Construction Phase Plan obligations

• scope creep — Managing and documenting scope creep

• payment chasing — Following up on unpaid invoices

• terms conditions — What your contract should include

• getting paid — Applications for payment, retention, and small claims