Ben SnapeIf you run an architectural practice in the UK, two contract types will affect your working life more than almost anything else: JCT and NEC.
They govern the terms under which the vast majority of UK construction projects are delivered, and the terms under which you, as architect, are liable, paid, and either protected or exposed.
Most architecture schools teach contracts briefly and reluctantly. Most practices rely on a standard form they inherited from a previous principal, or whatever the client’s solicitor specifies, without much interrogation of whether it actually fits the project.
That is a commercial vulnerability.
The choice between JCT and NEC has direct consequences for fee recovery, dispute resolution, cost overrun risk, and your overall position in the delivery team.
This post covers both contract families in detail: what they are, how they work, how they differ, and what the choice means for your practice.
Why architects need to understand NEC & JCT contracts
Architects are not solicitors, and nobody expects them to draft contract clauses from scratch. But architects occupy a specific position in most UK contracts, which comes with legal obligations that cannot be navigated safely without understanding the framework they exist in.
Under JCT, the architect is typically named as the Contract Administrator (CA), a role with specific certification duties, time bars, and liability exposure.
Fail to issue a certificate on time or instruct a variation incorrectly, and the consequences can cascade into cost overruns, contractor claims, and client complaints that erode both the fee and the relationship.
Under NEC, the Contract Administrator is replaced by a Project Manager (PM). This role is usually filled by a dedicated project management professional on larger infrastructure schemes, but architects are increasingly being asked to fill on building projects. It requires a fundamentally different approach: proactive, time-sensitive, and continuous.
Beyond administration, understanding contracts is increasingly a business development advantage.
Clients appointing architects for public sector, healthcare, education, and infrastructure work expect their design team to be fluent in NEC.
Practices that cannot demonstrate that fluency lose work to those that can.
What is a JCT contract
The Joint Contracts Tribunal was established in 1931, originally by the Royal Institute of British Architects, to produce standard form contracts for the UK building industry. It has produced contracts in collaboration with a range of industry bodies ever since and remains the dominant contract family for private sector building work in the UK.
By most estimates, JCT contracts are used on approximately 70% of UK building projects by value.
JCT contracts are built on decades of established case law. That body of legal precedent is one of JCT’s most significant practical advantages: when a dispute arises, there is usually a relevant court judgment that indicates how a clause should be interpreted.
The contract defines at the outset which party bears which risks, and the contractor prices accordingly. Once the works are underway, the contract administrator manages deviations from the agreed scope through formal instructions and certifications.
The main JCT contract types
The JCT suite covers a wide range of project types and procurement routes. The contracts architects most commonly encounter are:
Minor Works Building Contract (MW / MWD 2024)
The simplest JCT form, designed for straightforward building work typically valued up to around £500,000, where the scope is well-defined and the works can be managed by a single contract administrator.
Intermediate Building Contract (IC / ICD 2024)
More detailed than MW but less complex than SBC, suited to projects of moderate complexity. An architect or contract administrator is appointed and detailed provisions on subcontracting and quality are required.
Standard Building Contract (SBC 2024)
The comprehensive JCT form for substantial building works: major new builds, large-scale commercial developments, and multi-storey residential schemes. It comes in three variants: SBC/Q (with quantities), SBC/AQ (approximate quantities), and SBC/XQ (without quantities), and includes detailed provisions for variations, extensions of time, loss and expense, and payment.
Design and Build Contract (DB 2024)
Used where the employer wants to transfer design responsibility to the contractor. The architect is typically engaged by the employer pre-contract to develop the Employer’s Requirements, then novated to the contractor post-appointment.
Target Cost Contract (TCC 2024)
New to the 2024 edition, this adds a JCT-flavoured target cost mechanism with pain/gain sharing. This bridges some of the gap between JCT’s traditional risk-allocation structure and the collaborative cost arrangements that NEC has long offered.
It is still very new and has a limited track record, but it signals a direction of travel.
What is a NEC contract
The New Engineering Contract was first published in 1993 by the Institution of Civil Engineers, specifically in response to industry criticism that traditional contracts like JCT were structured in a way that encouraged adversarial behaviour.
The foundational principle of NEC is that the parties, and the project manager and supervisor, must act in a spirit of mutual trust and cooperation. This is a contractual obligation that shapes how every other clause in the suite is applied.
NEC is the dominant contract family for UK public sector and infrastructure work. The UK Government Construction Board recommends NEC4 for publicly funded schemes, and it is standard across transport, utilities, healthcare, and education procurement.
On private sector building projects, NEC adoption is growing but still relatively limited compared to JCT.
The main NEC4 contract types
The NEC4 suite is broader than JCT and covers more procurement scenarios:
Engineering and Construction Contract (ECC)
The main works contract, equivalent to JCT SBC or DB in function. It is the contract most architects encounter when working on NEC projects.
Engineering and Construction Subcontract (ECS)
The subcontract form for use beneath an ECC, mirroring the main contract’s structure and terminology to maintain consistency through the supply chain.
Professional Service Contract (PSC)
The consultant appointment form within the NEC4 suite. Used to appoint architects, engineers, project managers, and other consultants on NEC projects. It operates on the same core principles as the ECC.
On fully NEC-procured projects, the expectation is that consultants will be appointed on a PSC to ensure cultural and procedural consistency across the entire delivery team.
Professional Service Short Contract (PSSC)
A simplified version of the PSC for lower-complexity or shorter-duration consultant appointments where full NEC management procedures are not warranted.
Engineering and Construction Short Contract (ECSC)
A simplified ECC for straightforward, low-risk projects where the full ECC management procedures would be disproportionate.
Term Service Contract (TSC)
This contract is used for ongoing maintenance or facilities management services over a defined term.
The NEC4 payment terms explained
The six main options within the ECC are one of the most important things to understand about NEC, because they fundamentally determine how cost and risk are distributed:
Option A – Priced contract with activity schedule: this is the closest NEC equivalent to a traditional lump sum. Most risk sits with the contractor, and the scope is well-defined.
Option B – Priced contract with bill of quantities. Similar to Option A in risk allocation but uses a bill of quantities rather than an activity schedule for pricing.
Option C – Target cost with activity schedule. The contractor and client share a target cost, with a pain/gain mechanism splitting over- or under-spend between them. Cost transparency (open-book accounting) is a must. This is the primary NEC option used for Early Contractor Involvement arrangements and complex building projects where a fixed price at tender is not credible.
Option D – Target cost with bill of quantities: the target cost equivalent of Option B.
Option E – Cost reimbursable. The contractor is paid actual defined cost plus a fee. Most risk sits with the client. This NEC payment term is used for urgent or highly uncertain works where the scope cannot be reliably priced in advance.
Option F – Management contract. The contractor manages the works through subcontractors and is paid a management fee. This NEC payment term is least commonly used in modern UK practice.
The architect’s role under NEC
Under an NEC ECC, there is no Contract Administrator role. Instead, there is a Project Manager (PM), which is typically a dedicated construction or project management professional on major infrastructure schemes, and a Supervisor, who monitors the works on site.
On building projects where architects take the PM role, the workload is substantially different from JCT contract administration.
The NEC PM must:
- accept or respond to the contractor’s programme updates;
- raise and manage early warnings;
- assess and respond to compensation event notifications within tight timeframes;
- maintain the early warning register;
- keep the accepted programme live as a dynamic management document throughout the project.
JCT vs NEC: the core differences
Philosophy and culture
JCT starts from the assumption that the parties’ interests may diverge, and the contract’s job is to define what happens in each scenario.
NEC starts from the assumption that the parties should work together proactively to avoid problems arising. These assumptions produce different project cultures, different commercial behaviours, and different risk profiles when things go wrong.
JCT’s legal clarity is a genuine advantage in adversarial situations. NEC’s collaborative structure produces better outcomes when all parties engage with it properly. A client who will not engage with early warning meetings or programme updates gets very little out of NEC’s collaborative machinery.
Risk allocation
Under JCT, risk is largely allocated at the tender stage. Under NEC, compensation events provide a mechanism for equitable re-allocation of risks that were not foreseeable at contract award.
Changes and variations
Under JCT, changes are managed as variations: the Contract Administrator issues an instruction, the contractor prices it, and time and cost are assessed separately through distinct contract mechanisms.
Under NEC, changes are compensation events: a single mechanism that assesses both time and cost together, prospectively, before the work is carried out. The contractor submits a quotation; the Project Manager assesses it; both parties agree on the impact before proceeding.
Programme management
Under JCT, the contractor submits a programme at the start of the project, which is used as a reference point for assessing extensions of time. There is no contractual obligation to update it regularly, and in practice the JCT programme often becomes a historical document rather than a live management tool.
Under NEC, the accepted programme is a central contractual instrument. It must be updated regularly to show actual progress, forecast completion, and the impact of compensation events.
The Project Manager must formally accept or reject each revision. The accepted programme is the reference point for assessing every compensation event. This creates rigour but also administrative load (PlanMan helps make it easier), because teams need systems in place to manage the project phases and programme documents across the full project lifecycle.
Early warning obligations
JCT has no formal early warning system. Good practice encourages early communication of potential problems, but there is no contractual obligation to notify a risk before it materialises.
NEC Clause 15 imposes a contractual duty on both the Project Manager and the Contractor to notify each other as soon as either becomes aware of any matter that could affect time, cost, or quality.
This triggers a formal early warning meeting and an entry in the early warning register. The register is a live document throughout the project.
Administration burden
JCT is typically described as having a lighter ongoing administration burden. Once the contract is in place, the CA certifies payment applications, issues instructions when needed, and formally responds to contractor notices.
NEC demands continuous active management. The Project Manager is reviewing and accepting programmes, managing the early warning register, assessing compensation event quotations, and maintaining an audit trail of every significant project decision, from the first day to the last.
Dispute resolution
Both contract families include adjudication as a mandatory mechanism under the Housing Grants, Construction and Regeneration Act 1996. Either party can refer a dispute to adjudication at any time during the project, and the adjudicator’s decision is temporarily binding pending final resolution.
Beyond adjudication, JCT uses arbitration or litigation as the final dispute resolution route, with decades of case law providing interpretive guidance.
NEC offers a choice between adjudication, arbitration, and tribunal (litigation) depending on the option selected in the Contract Data, with a structured escalation process that encourages senior management engagement before adjudication is invoked.
In practice, the adversarial character of JCT means disputes do arise more frequently — particularly at final account when accumulated variation claims and extension of time entitlements are reconciled.
How contract knowledge affects business growth
Understanding the differences between JCT and NEC has direct commercial consequences for architectural practices:
Fee recovery
Under JCT, the architect’s fee is structured around stage completions and the CA certification role. The work is relatively predictable.
Under NEC PSC, the compensation event mechanism means the architect’s own fee is potentially adjusted during the commission: up if the client changes scope, down if performance is not met.
Reduced dispute exposure
Practices that understand their CA obligations under JCT, and meet them precisely, avoid the certification errors that generate claims.
Practices fluent in NEC’s early warning system catch problems before they become disputes. Both lead to better client relationships and fewer write-offs.
Access to public sector frameworks
The UK public sector has consolidated around NEC4 as its contract of choice. Practices that cannot demonstrate NEC competence are excluded from these competitions.
Given that public sector work is often more recession-proof than private sector commissions, this is a meaningful strategic gap.
The advisory positioning
Architects who understand procurement well enough to advise clients on which contract form suits their project are operating at a genuinely different level of engagement.
This advisory capacity is one of the higher-margin services available to architectural practices and one of the clearest ways to differentiate from competitors.
This leads us back to the broader argument for practices to position themselves as architectural businesses rather than studios.
Specification writing
The choice of contract form directly affects how specifications, employer’s requirements, and design obligations are drafted.
Under JCT, the architect’s specification becomes the Employer’s Requirements, a document with very specific legal function that must be drafted differently from a traditional specification.
Under NEC, the “Scope” is the equivalent document, and how it is written determines the boundaries of the compensation event mechanism.
How PlanMan supports contract administration
PlanMan.app is a project management platform built specifically for UK architects and town planners. Our features map closely onto the administrative demands of both JCT and NEC contract forms.
Both JCT and NEC generate substantial volumes of documentation, and PlanMan’s document management module provides version-controlled, cloud-hosted storage with access from any device, including on site via the PlanMan mobile app.
PlanMan’s client communications module and project-specific instant chat keep all correspondence organised against the project with timestamps. This is both convenient and helps improve your risk management.
The co-consultants module and granular permission controls allow the practice to bring external team members into the project environment with precisely the access they need. Each consultant sees what is relevant to them; the audit trail of what was shared, when, and with whom stays clear.
Our quote and invoice management features let practices structure fee proposals and invoices against project stages, track what has been certified and what is outstanding, and integrate with accounting platforms via Xero, FreshBooks, or Sage.
Start your free 30-day trial and see how it fits your practice’s workflow!