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MC Architectural Design Contract Administration

JCT Contracts · Client Guide

A Client’s Guide

Contract
Administration
Explained

How your building contract is professionally managed — from signing to final certificate

JCTStandard Contracts

FairImpartial Certifier

Start–EndSigning to Final Account

This guide has been prepared by MC Architectural Design to explain what happens once you have signed a building contract — who does what, when money changes hands, and how changes, delays and defects are dealt with. It is written in plain English so you know exactly what to expect from your contractor, from us, and from yourself.

Please note: this guide is general information based on the JCT family of contracts, most often the JCT Minor Works Building Contract 2016. It is not legal advice. The exact terms, dates and percentages on your project are those written in your signed contract.

Section 1.0

What Is Contract Administration?

A signed contract is only the start — it has to be managed

When you employ a builder, you enter into a building contract — a legal agreement that sets out what will be built, for how much, and by when. Contract administration is the professional management of that agreement during the construction phase. The person who does this is called the Contract Administrator (the JCT contracts use the title “Architect/Contract Administrator”).

Your Contract Administrator is appointed by you, but once the contract is signed they have two jobs. They act as your agent — looking after your interests, issuing instructions and keeping you informed. And when they value work, decide on extra time or certify payment, they must act as a fair and impartial certifier between you and the contractor, applying the contract as written.

Who Does What — The Three Parties

Party 1

You — The Client

“The Employer” in JCT

Pays for the work, provides access to the site and makes decisions. Signs the contract with the builder.

Party 2

The Contractor

Your builder

Builds the works to the drawings and specification, for the agreed price, by the agreed date. Runs the site day to day.

Named in the Contract

Contract Administrator

Appointed by you

Runs the contract: issues instructions, values the work, certifies payment, deals with changes and delays, and signs off completion.

What a Contract Administrator Is Not

Not the site manager. The contractor controls the site, the workforce and the way the work is done — including site safety.
Not a full-time inspector. Site visits are periodic. We inspect the work in general, but we cannot see every brick laid or guarantee the builder’s workmanship.
Not on “your side” when certifying. When valuing work or assessing a delay, the contract requires a fair decision — even when that decision is not the one you hoped for.

💡

Plain English

Think of the Contract Administrator as the referee who also knows your game plan. We make sure the contractor delivers what you are paying for, that you only pay for work properly done, and that the rules you both signed up to are followed — fairly, and in writing.

Section 2.0

Choosing the Right Building Contract

A quote, a handshake or a string of text messages is not a building contract. A proper written contract protects both you and your builder by setting out, in advance, how the common problems will be dealt with — changes, delays, payment, defects and what happens if things go wrong. We normally recommend a standard form published by the Joint Contracts Tribunal (JCT), the most widely used building contracts in the UK.

Which JCT Contract Suits Your Project?

Common JCT Forms for Residential & Small Commercial Work

1

JCT Homeowner Contract (HO/C)
Short, plain-English contract for homeowners dealing directly with a builder on smaller domestic jobs. It can be used with a consultant, but it does not give a Contract Administrator the full certifying role.

2

JCT Minor Works Building Contract 2016 (MW) — our usual choice
For simple, well-defined work with drawings and a specification and a fixed price — extensions, loft conversions, refurbishments and small new builds. A Contract Administrator is named in the contract and runs it on your behalf.

3

JCT Minor Works with Contractor’s Design (MWD)
As above, but where the contractor designs a specific part of the work — for example a steel frame, roof trusses or a heating system.

4

JCT Intermediate Building Contract (IC)
For larger or more complex projects with more trades, specialist sub-contractors or a longer programme, where fuller procedures are needed.

What Goes Into the Contract

The Money

The contract sum, how often the contractor is paid, the retention percentage held back (usually 5%), and any provisional sums for items not yet fixed.

The Time

The start date, the completion date, and the rate of liquidated damages — a pre-agreed weekly sum you may deduct if the work finishes late without a valid reason.

The Work

The contract drawings, specification and schedule of work — together they define exactly what the contract sum includes.

The Protection

Insurance, the rectification (defects) period, CDM duties, and what happens in a dispute or if either party needs to end the contract.

Typical Scenario The Handshake Extension

Single-Storey Rear Extension, Hampshire — Quote Accepted by Text Message

A homeowner accepted a builder’s one-page quote of £68,000 by text. There was no contract, no specification beyond the planning drawings, and no agreed finish date. Halfway through, the builder presented a list of “extras” worth £14,000 — underfloor heating, a larger rooflight and upgraded bifold doors — saying they were never in the price. The homeowner believed they were. The job also ran eleven weeks late while the builder worked on another site.

With nothing in writing, there was no way to show what the £68,000 included, no agreed completion date, and nothing to deduct for the delay. The dispute ended with the homeowner paying most of the extras simply to get the job finished.

⚠️ Lesson: a JCT Minor Works contract with a proper specification would have fixed the scope, the price and the completion date — and given a clear route for agreeing any genuine changes in writing before they were built.

Section 3.0

Before Work Starts on Site

Most contract problems can be traced back to the weeks before the builder arrived. Time spent getting the paperwork right at this stage is the cheapest insurance you will ever buy.

From Tender to Start on Site

01Tender to selected builders

›

02Compare & clarify prices

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03Prepare & sign contract

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04Pre-start meeting

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05Start on site

Pre-Start Checklist

✓

Contract signed by both parties — before anyone starts work, with the drawings and specification attached and initialled.

✓

Insurance certificates received — the contractor’s public liability and employer’s liability, plus insurance of the works. Tell your own home insurer about the building work.

✓

CDM appointments in place — Principal Designer and Principal Contractor appointed in writing where needed, and a Construction Phase Plan prepared by the contractor.

✓

Building Control notified — and any planning conditions that must be cleared before starting have been discharged.

✓

Party wall matters settled — notices served and any awards agreed with neighbours where the Party Wall etc. Act 1996 applies.

✓

Programme received — a simple timeline from the contractor showing the key stages and the completion date.

✓

Site arrangements agreed — access, working hours, parking, skip location, welfare facilities and which parts of the house stay in use.

✓

Lines of communication confirmed — who speaks to whom, and that all instructions go through the Contract Administrator.

The Pre-Start Meeting

Before work begins we hold a meeting on site with you and the contractor. We walk through the contract, the programme, payment dates, site rules, health and safety arrangements and how changes will be handled. Minutes are issued to everyone, so all parties start from the same page.

💡

Plain English

Never let the builder start before the contract is signed and the insurance is in place. Once work has begun, your bargaining position changes — and any gaps in the paperwork become much harder to fix.

Section 4.0

During Construction — Instructions, Changes & Delays

Once the builder is on site, the Contract Administrator becomes the formal point of contact under the contract. Everything that changes the work, the price or the time goes through us — and is recorded in writing.

Site Visits & Reports

We visit at key stages — foundations, structure, first fix, pre-plaster and completion — to check the work in general is going in as designed. Each visit is followed by a short written report with photographs.

Architect’s / Contract Administrator’s Instructions

Any change, clarification or extra information is issued as a numbered written instruction. Only instructions issued by the Contract Administrator are valid under the contract.

Variations — Changes to the Work

If you want something added, removed or changed, we ask the contractor to price it first. You then decide with the cost and any time impact in front of you — before the work is done, not after.

Extensions of Time

If the job is delayed by something that is not the contractor’s fault — your changes, late information, exceptional weather — the contractor may be entitled to more time. We assess each claim fairly and fix a new completion date where it is justified.

Progress Meetings & Records

Regular progress checks against the programme, with minutes, photographs and a running record of instructions, costs and dates — so there is always an accurate picture of where the project stands.

The single most common cause of cost overruns and disputes on small projects is the client instructing the builder directly — “while you’re here, could you just…”. Every informal request is a potential extra charge and a potential claim for more time.

Typical Scenario “Could You Just…” — Direct Instructions on Site

Loft Conversion, Portsmouth — Four Small Changes, One Large Bill

During a loft conversion, the client asked the builder on site to move the en-suite door, add two extra sockets, switch to a larger dormer window and tile the full shower wall rather than half. Each request seemed small and nothing was written down. At the end of the job the builder’s final account included £6,800 in extras and a claim that the window change had added three weeks to the programme — which also meant the client could no longer deduct damages for the late finish.

✅ How contract administration prevents this: each request is passed to the Contract Administrator, priced by the contractor, agreed by you and issued as a written instruction with its cost and time effect fixed there and then. No surprises in the final account.

Section 5.0

Paying the Contractor — Valuations & Certificates

Under a JCT contract you do not pay the builder whenever they ask. You pay against a certificate issued by the Contract Administrator, usually once a month, for the value of work properly carried out to date — less a small retention and less anything already paid.

The Monthly Payment Cycle — JCT Minor Works 2016

01Valuation date
Monthly

›

02Due date
+7 days

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03Certificate issued
Within 5 days of due date

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04Pay less notice
If needed — 5 days before final date

›

05You pay
By 14 days after due date

How It Works in Practice

The contractor sends an application setting out what they believe they are owed — work done, materials on site and any agreed variations.
We check it against the work on site. We value only work that has actually been done and is in line with the contract — not work that is planned, or materials that have not arrived.
We issue a payment certificate to you and the contractor stating the amount due. This is the figure you pay.
If you intend to pay less than the certified sum — for example to deduct damages for late completion — a formal “pay less notice” must be given in time and state the reason. We prepare this with you.
You pay the builder directly by the final date for payment. We never handle your money.

Retention — Your Safety Net

A small percentage of each payment (usually 5%) is held back. Half is released at practical completion; the rest at the final certificate, once defects have been put right.

Deposits & Advance Payments

Avoid paying for work not yet done. If a deposit is unavoidable — for example for made-to-order windows — we agree safeguards first, such as proof of order or goods marked as yours.

Typical Scenario Paid Ahead of the Work

Kitchen Extension, Waterlooville — 60% Paid, 35% Built

A client without a Contract Administrator paid their builder in round-number stages on request: £10,000 to start, £15,000 “for materials”, £12,000 at wall plate. When the builder stopped turning up, a surveyor valued the work on site at around £21,000 — against £37,000 paid. The client had to fund a second builder to finish, at a higher price, while pursuing the first through the courts.

✅ With certified payments: you only ever pay for work properly done, less retention. If a contractor walks away, you are never significantly out of pocket — and the certificates provide a clear, independent record of value.

Section 6.0

Practical Completion & Handover

Practical completion is when the building becomes yours again

Practical completion is the point at which the work is finished for all practical purposes — the building can be safely used, and any items still outstanding are minor. It is one of the most important dates in the contract, and it is the Contract Administrator who decides when it has been reached.

Our Completion Inspection

When the contractor tells us the work is complete, we inspect it and prepare a snagging list of anything unfinished or not to standard. Once the work reaches practical completion, we issue the Certificate of Practical Completion.

What the Certificate Triggers

On the Date of Practical Completion

1

Half the retention is released

Typically 5% held drops to 2.5% in the next payment certificate.

2

Liquidated damages stop running

If the work finished after the (extended) completion date, we certify this so you can deduct damages at the agreed weekly rate.

3

The rectification period begins

The contractor must return to put right defects that appear during this period — see Section 7.

!

Responsibility for the building returns to you

Check with your insurer that the new work is covered from this date.

Handover Documents to Collect

Building Control completion certificate
Electrical, gas and heating test certificates and commissioning records
Product guarantees and warranties — windows, roofing, boilers, appliances
The Health & Safety File from the Principal Designer, where CDM applies
Keys, codes, manuals and as-built information

Section 7.0

The Rectification Period & Final Certificate

Some defects only show themselves once a building is lived in — a sticking door, a hairline crack as plaster dries, a slow leak. The rectification period (often called the defects period) gives you a contractual right to have these put right at no cost. Under JCT Minor Works it is three months unless a different period is written into the contract; we often recommend six or twelve months for larger works.

From Practical Completion to Final Certificate

01Practical completion

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02You log defects as they appear

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03End-of-period inspection

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04Defects made good

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05Final certificate

During the Rectification Period

Keep a simple list of any defects with dates and photos, and send it to us — not straight to the builder.
Report anything urgent immediately — leaks, electrical faults or safety issues cannot wait for the end of the period.
Let the builder back in at reasonable times to carry out repairs. Refusing access can weaken your right to have the defect fixed at their cost.

Closing the Contract

At the end of the period we inspect the work and issue a schedule of defects. When everything has been put right, we issue the Certificate of Making Good. Meanwhile the contractor sends us their final account documents — under JCT Minor Works, within three months of practical completion unless the contract says otherwise. We check every variation and adjustment against the instructions issued, agree the final contract sum and then issue the Final Certificate, which releases the last of the retention.

The Final Certificate is the full stop at the end of the contract. It is an important legal document, and it should only be issued once every defect has been put right and every figure in the final account has been checked.

💡

Plain English

The last slice of retention is your leverage to get the snags fixed. Don’t release it early as a goodwill gesture — wait until we confirm the defects have been properly put right.

Section 8.0

Your Role as Client — Do’s and Don’ts

A building contract works best when everyone sticks to their role. Your part is simple, but it matters — most of the problems we see on site start with a well-meaning client stepping outside the contract.

Please Do

Help the Contract Work

✓

Send every request for a change to us, not the builder

✓

Make decisions on finishes and fittings on time — late choices cause delay claims

✓

Pay certified sums in full and on time

✓

Tell us straight away if you have concerns about quality, progress or safety

✓

Keep a contingency of around 10% for unforeseen work

Please Don’t

Step Outside the Contract

✕

Give instructions to the builder or their trades directly

✕

Pay without a certificate, or pay cash “to save the VAT”

✕

Bring in your own trades while the contractor is still on site without agreeing it first

✕

Move back in or take over rooms before completion without agreement

✕

Withhold money without a valid pay less notice

A friendly relationship with your builder is a good thing — offer the tea, say thank you, ask how things are going. Just keep decisions about the work, the money and the time inside the contract, where they are recorded and fair to everyone.

Example Scenario A Contract That Did Its Job

Two-Storey Side Extension, Hampshire — Delay Handled by the Book

On a JCT Minor Works contract with a contract sum of £142,000, the contractor finished four weeks late. Two weeks of that delay were caused by the client changing the kitchen layout after first fix, so we granted a two-week extension of time. The other two weeks were the contractor’s own doing. We issued a certificate of non-completion, the client issued a pay less notice, and damages at the agreed rate of £350 a week were deducted from the next payment. Because every step followed the contract, the contractor accepted the position without dispute.

✅ Result: a fair outcome for both sides, reached in writing within days — no solicitors, no adjudication and no damaged relationship on site.

Section 9.0

How MC Architectural Design Can Help

MC Architectural Design provides a full contract administration service for residential and small commercial projects across Hampshire, West Sussex, East Sussex and Surrey. We can carry your project through from the drawings we prepared, or step in as Contract Administrator on a scheme designed by others.

Tender & Contractor Selection

We prepare tender documents, invite prices from vetted contractors on our approved list, and compare the returns line by line so you can choose with confidence.

Contract Preparation

We recommend the right JCT form, complete the contract particulars, assemble the contract documents and arrange signing before work starts.

Site Visits & Reports

Periodic inspections at key stages, each followed by a written report with photographs, so you always know how the work is progressing.

Instructions & Variations

Every change is priced, agreed and issued as a numbered written instruction — keeping the cost and programme under control.

Valuations & Certificates

Monthly valuations of work done, payment certificates on time, and help with pay less notices where they are needed.

Completion & Final Account

Snagging, practical completion, the rectification period inspection, the final account and the Final Certificate that closes the contract.

Our Contract Administration File — Every Project, Every Stage

01Appointment

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02JCT Contract

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03Pre-Start

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04Site Visit Reports

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05Instructions

06Variations

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07Interim Certificates

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08Practical Completion

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09Rectification Period

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10Final Account

MC Architectural Design Ltd is an architectural design practice with offices in Southampton (head office), Portsmouth, Chichester, Hove and Guildford. Where needed, we can also act as your CDM Principal Designer and Building Regulations Principal Designer on the same project — one point of contact from design through to the Final Certificate.

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with confidence?

Get in touch with MC Architectural Design today. We will talk through your project, recommend the right building contract and provide a contract administration fee proposal with no obligation.

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02392 984788

Email Us

designers@mcadesign.uk

Offices

Southampton (Head Office)
Portsmouth · Chichester
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Services

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Contract Administration

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ContractAdministrationExplained

Contents

What Is Contract Administration?

Who Does What — The Three Parties

Choosing the Right Building Contract

Which JCT Contract Suits Your Project?

What Goes Into the Contract

Before Work Starts on Site

Pre-Start Checklist

During Construction — Instructions, Changes & Delays

Paying the Contractor — Valuations & Certificates

How It Works in Practice

Practical Completion & Handover

Our Completion Inspection

What the Certificate Triggers

The Rectification Period & Final Certificate

During the Rectification Period

Closing the Contract

Your Role as Client — Do’s and Don’ts

How MC Architectural Design Can Help

Tender & Contractor Selection

Contract Preparation

Site Visits & Reports

Instructions & Variations

Valuations & Certificates

Completion & Final Account

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