Milestone-Based Construction Contracts: The Safest Way for Kenyans in the Diaspora to Pay for Building

Sending construction money to Kenya should not depend on a reassuring phone call, a photograph of a wall or a request marked “urgent.” For a diaspora homeowner, the stronger question is: what defined work has been completed, who has independently checked it, and what amount is now payable under the contract?

A well-designed milestone construction contract connects those questions. It divides the project into measurable work packages, specifies inspection and payment procedures, and records what happens when work is incomplete, a change is needed or the parties disagree. It also gives the contractor a predictable route to legitimate payment instead of leaving cash flow to informal approval.

No payment arrangement is universally the “safest,” and stage payments do not guarantee completion or remove construction risk. Their value comes from the quality of the scope, professional oversight and enforceable project-specific terms—not the word “milestone” on the cover. This guide explains how to structure stage payments for building a house in Kenya without confusing photographs, retention, advances and actual certification.

1. What a milestone-based construction contract should do

A milestone is an agreed, objectively checkable package of work with a defined value or valuation method. The contract should identify the relevant drawings and specifications, completion criteria, inspections, supporting documents, certifier and payment deadlines. “Roof level reached” is not enough if one party means the wall plate is installed and the other means a complete weatherproof roof.

Separate three events: the contractor applies for payment, the named professional assesses/certifies entitlement, and the owner pays the sum due. A contractor's invoice is a request, not automatically proof that the milestone has been achieved. Equally, an owner should not disregard a properly certified entitlement merely because an informal relative has expressed a different opinion.

Choose the underlying contract basis first. Fixed-price, remeasurement, labour-only and cost-plus arrangements have different risks and evidence requirements. Adding stage-payment labels does not turn an incomplete labour-only price into a full materials-and-labour contract.

A practical diaspora building contract should also specify who may instruct work. Name the owner or authorized representative, contract administrator, architect, engineer and QS as appropriate. Define their authority. A family member who facilitates site access should not accidentally become the person approving structural alterations or expensive finishes.

2. Start with coordinated drawings, a BQ and an all-in funding plan

Milestone values are only as reliable as the scope behind them. Obtain coordinated architectural, structural and relevant services information, specifications and a measured bill of quantities. Identify exclusions, provisional sums, owner-supplied items, taxes, site assumptions and how discrepancies between documents are resolved.

Ask the QS to reconcile work-package values to the agreed contract sum. Do not copy a universal set of percentages from another project: a bungalow, maisonette and difficult sloping site can have very different substructure, roof and services proportions. An expensive early milestone can leave the owner paying ahead of completed value; an unrealistically small early allocation can starve legitimate work of funds.

Keep the project budget separate from the contractor's price. Professional fees, approvals, utilities, external works and contingency may fall outside that price. Our diaspora construction handbook explains how to combine legal, technical and remote-reporting controls before major remittances.

Agree currency, transfer costs, exchange-rate risk and the amount that must arrive in the receiving account. Confirm that the construction programme matches the funding plan. A milestone schedule is not a substitute for having funds available when properly certified payments fall due.

3. Define each construction stage before agreeing its price

The following schedule is a planning framework, not a universal sequence, percentage allocation or site-specific technical design. The appointed professionals must adapt it to the approved building and coordinate inspections before work is concealed.

Stage	Scope to define precisely	Evidence and hold points to agree
Pre-start/site establishment	Required approvals, appointments, access and specified preliminary works	Document checks and evidence of completed preliminaries; distinguish earned value from an advance
Foundation/substructure	Setting out, excavation, foundation construction and other included below-ground/floor work	Ground/design decisions, engineer inspections before concealment, relevant tests and measured quantities
Walling/lintel/frame	Wall runs, structural frame, lintels and any included slab or staircase work	Approved revisions, structural hold-point records, alignment and specification checks
Roof/weather protection	Specified roof structure, covering or slab system, flashings, waterproofing and drainage interfaces	Structural and workmanship inspections and relevant water/weatherproofing checks
Plastering and MEP	Coordinated first-fix services, concealed installations, plaster/render and specified testing	Inspection before covering, service test records and approved product information
Final finishes/commissioning	Agreed finishes, fittings, functioning services, external work included in scope and handover records	Snagging, commissioning, completion criteria, warranties and applicable approvals

Foundation level: inspect before the evidence disappears

Do not define this stage simply as “foundation complete.” Specify which excavation, foundation, reinforcement, concrete, masonry, backfill, service penetrations and floor components are included. Ground conditions may require an engineer's decision before the original assumptions remain valid.

Arrange notice periods so the appropriate inspection can occur before concrete is placed or work is covered. Retain inspection records and relevant test results. A later photograph of a finished floor cannot establish what reinforcement or ground preparation lies beneath it.

Walling and lintel level: distinguish masonry from structural completion

State whether the stage includes columns, beams, lintels, upper-floor elements, stairs or only specified masonry. Reference the approved drawings and revisions. The fact that a wall has reached a certain height does not establish that every structural detail or quantity has been checked.

Do not accept an owner or relative informally changing openings, wall positions or structural elements because they look better on video. The relevant designer must review the change, and its cost and time implications must enter the variation process.

Roof level: define the completed system

For a pitched roof, identify structure, covering, flashings, rainwater goods and related interfaces included in the stage. For a concrete roof, identify the structural work, falls, waterproofing, outlets and other specified components. These are different packages, not interchangeable “roof percentages.”

Agree the inspection and testing evidence appropriate to the system. Avoid releasing the entire roof allocation merely because materials have been delivered, unless the contract separately permits a properly safeguarded materials payment.

Plastering, MEP and final finishes: sequence matters

Mechanical, electrical and plumbing work often becomes concealed. Agree the first-fix and test hold points before plaster, ceilings or finishes hide it. Identify who checks compliance and which competent or licensed specialists are required for the actual work.

For finishes, approve samples, models, quantities and locations before procurement. Define commissioning and handover, not just installation. A fitted tap, light or pump is not proof that the relevant system operates satisfactorily.

4. Independent verification: use the right professional for the right decision

The NCA's project-registration guidance requires current contractor licences, appropriately registered/licensed consultants, approved drawings and consultant supervision commitments. It also identifies the owner/developer as responsible for project registration. Ask for the actual records, not simply assurances that the builder “has NCA.”

For financial valuation, the official BORAQS professional-services schedule describes QS site visits, measurement and valuations for interim payments. Use measured work and the agreed BQ/rates to support the payment assessment. Confirm who, under your chosen contract, formally issues the certificate; the QS's valuation and the contract administrator's certificate may be separate steps.

Structural verification is a different responsibility. The Engineers Act addresses professional engineering work and licensing. Safety-critical engineering inspections and decisions require the appropriately qualified, registered and currently licensed professional—not a general progress update.

A clerk of works is useful, but is not automatically a structural engineer

The BORAQS schedule provides for a clerk of works where more frequent or continuous inspection is needed, operating under the architect's direction and control. A competent clerk can improve site observation, records and early identification of departures. That appointment does not automatically authorize structural design or replace the engineer's responsibilities.

Check qualifications, current credentials, experience, independence and written scope. Avoid relying on the vague label “certified clerk” without knowing the actual qualification and authority. Verify the QS through the BORAQS register and confirm the engineer's current status directly with EBK.

Photos, drone footage, invoices and delivery notes are corroborating evidence. They do not alone prove measured quantities, hidden workmanship or structural adequacy. Define independent access and site-inspection arrangements before a payment dispute makes cooperation difficult.

5. Retention: separate the deduction rate from the cap

Retention is an agreed portion of money otherwise earned that is withheld under the contract, subject to its release provisions. It can provide a financial incentive to complete obligations and address defects, but it is not insurance, independent escrow or a guarantee that rectification costs will be covered.

The strategy often discussed by homeowners is to retain 5%–10%. Those figures must be negotiated and properly defined; they are not a universal statutory deduction for every Kenyan home. Specify the base, deduction rate, maximum retention fund, custody arrangements, release events, certificates and deadlines.

For example, a 10% deduction from each eligible certificate with a cap of 5% of the contract sum is different from withholding 10% of the entire contract until the very end. The first arrangement stops further deductions once its agreed cap is reached. Confusing the two can create a substantial cash-flow dispute.

PPRA's public-procurement standard documents and filled tender schedules illustrate this distinction. One official public tender specifies a 10% deduction from payments with a 5% contract-value limit. That is an example of particular public contract data—not a mandatory rule for a private residence.

A simple retention calculation

Assume, only for illustration, an eligible gross valuation of KSh 600,000 before other adjustments and with the retention cap not yet reached. A 5% deduction is KSh 30,000, leaving KSh 570,000. A 10% deduction is KSh 60,000, leaving KSh 540,000. Taxes, previous certificates, advance recovery and other permitted adjustments must be handled consistently under the actual contract.

Agree whether some retention is released at practical completion and the balance after the specified defects process. Define what certification is needed and how unresolved defects affect release. An owner should not withhold everything indefinitely without contractual or legal basis; the contractor should not assume the entire fund becomes payable merely because a calendar date has passed.

6. Is a six-month defects liability period enough?

A six-month defects period is sometimes proposed in contracts, and a particular public tender provides such an example. It does not establish a universal Kenyan statutory minimum or prove that six months is appropriate for your home, materials or building use.

If the parties consider a six-month arrangement, the advocate and professional team should review its suitability, start event, rectification procedure, retention release and interaction with applicable law, warranties and other rights. Do not assume that releasing retention or ending a contractual defects period extinguishes every later claim.

Be careful with online summaries of the NCA Defects Liability Regulations 2020, Legal Notice 64. The High Court in Republic v National Construction Authority & 2 others [2022] KEHC 333 quashed that notice. Its commonly quoted periods should not be presented as automatically operative law. Obtain advice on the current legal position and the actual project rather than copying either an old statutory summary or a generic six-month clause.

Keep a dated defects register, notify through the agreed channel, allow access and document rectification. Roof leaks, plumbing faults, electrical problems and workmanship defects need the relevant competent investigation; retention alone does not diagnose or repair them.

7. Use a cumulative payment ledger to avoid double payment

Track the original contract sum, approved variations, eligible work/materials, cumulative retention, advances and recoveries, certificates and actual transfers. Reconcile certificates separately from cash paid. A sum may have been certified but still unpaid; an advance may have been paid without yet becoming earned work.

Illustrative current-certificate calculation	KSh
Eligible cumulative gross valuation	2,000,000
Less cumulative retention	100,000
Less cumulative advance recovery	200,000
Less previous net interim certificates, excluding the original advance	1,100,000
Current net interim certificate	600,000

This is an invented arithmetic example, not a quotation or universal certificate form. It assumes a consistent basis with no other adjustments and leaves tax treatment outside the example. Reconcile any previously unpaid certificates and the unrecovered advance separately; do not deduct previous payments and previous certificates a second time.

A mobilisation advance needs its own purpose, amount, protection and recovery schedule. Where materials are paid for before incorporation, define ownership, identification, storage, insurance, inspection and risk. Off-site materials require particular care. Money in a contractor-controlled project account is not independent escrow simply because it is called “project money.”

8. Protect payment instructions against fraud and confusion

Pay the contractually identified beneficiary through traceable channels. Independently verify account details at the outset and any later change using an established contact route—not only the email or message announcing the change. Keep the invoice, certificate, approval and transfer reference linked in the project record.

If direct supplier payments are agreed, specify who orders and accepts materials, who owns them, how they are credited against the contract and who handles warranties or shortages. Avoid paying the supplier and later reimbursing the contractor for the same materials.

Agree response times that accommodate overseas banking and time zones without undermining payment obligations. A regular review meeting can resolve evidence gaps early. Formal notices and instructions should still follow the contract rather than disappear in a long WhatsApp conversation.

9. Control variations before they consume the next milestone

A variation changes the agreed scope, specification or other contractual requirement. Record the request, drawing revision, technical approval, price basis, time effect and person authorized to instruct it. Obtain agreement through the contract procedure before the affected purchase or work, subject to any narrowly defined emergency process.

Changing tiles, moving a wall, adding a room or upgrading a roof can affect more than the visible item. The designer and QS should assess related structural, services, cost and programme consequences. Do not allow a relative's on-site preference to become an unauthorized instruction.

State how additions and omissions are valued, how provisional sums are adjusted and what happens if the parties disagree. Update the contract forecast and remaining funding after approved changes. Paying every surprise from “contingency” without a record is not cost control.

10. Write balanced delay, suspension and termination provisions

A missed date or disputed certificate should trigger the agreed process, not an improvised takeover of the site. Have a Kenyan advocate address grounds for notices, cure periods, service methods, extensions of time, suspension, termination and the consequences for both parties.

Distinguish an owner-requested change, delayed approval, late payment, contractor default and circumstances outside the parties' control. Define how the relevant professional assesses time effects and what evidence is required. Do not label every delay a fundamental breach.

Termination provisions should address valuation of completed work, material ownership, advances, retention, documents, site security, demobilisation and permitted claims. Public-works models may contain notice periods or termination rights suited to their context; they are not automatically the correct terms for a private diaspora contract.

Get advice before suspending payment, replacing the contractor or taking control of stored materials. Preserve evidence and act through the required procedure. A carefully drafted contract protects the owner's investment while recognizing the contractor's legitimate entitlement and obligations.

11. Agree how disputes will be resolved before one arises

Set out a clear escalation process: written notice, a defined management/professional review, negotiation and any agreed mediation or other step. Identify participants and time limits. Avoid ambiguous clauses that appear to require incompatible forums or leave everyone waiting indefinitely.

If arbitration is chosen, obtain a properly drafted written arbitration agreement. Section 4 of Kenya's Arbitration Act addresses the writing requirement; section 7 provides for court interim protection. Agree the necessary scope, seat, appointment mechanism, rules and other terms with your advocate rather than copying an incomplete internet clause.

Arbitration is not automatically cheaper or faster for every dispute, and mediation depends on the applicable arrangement and participation. Discuss cost, enforceability, interim relief and the owner's overseas location. Define treatment of undisputed sums and continuing work while a dispute is addressed, subject to the contract and legal advice.

12. A payment-release checklist for diaspora homeowners

1. Check the application against the current contract, approved drawings and variations.
2. Confirm the milestone's precise scope and any agreed partial-completion rules.
3. Obtain the appropriate physical inspections, test records and concealed-work evidence.
4. Review the QS valuation and certificate issued by the contractually named certifier.
5. Reconcile retention, cap, advance recovery, previous certificates and actual payments.
6. Identify defects or disputed amounts through the required notice process.
7. Verify the beneficiary, bank details and credited-amount requirements.
8. Pay the sum due within the agreed period and retain the transfer evidence.
9. Update the cost forecast, decisions register and next inspection dates.

Use this sequence consistently, including when progress looks good. Controls are most effective when they are routine, fair and agreed before work starts—not introduced only after trust has broken down.

Frequently asked questions

Should I refuse every upfront payment?

Not necessarily. Properly justified advances or preliminary-work payments may be appropriate. Distinguish an advance from earned work and agree purpose, protection, evidence and recovery. A blanket rule can be as unhelpful as an unsecured large deposit.

Can I use equal percentages for every milestone?

Only if the agreed cost plan genuinely supports that allocation. Derive stage values from the actual scope and valuation basis rather than dividing the price into convenient instalments.

Is 10% retention automatically required?

No. Agree the deduction rate, base, cap and release process. A 10% certificate deduction and a 5% overall cap are different figures serving different functions; neither is a universal private-home rule.

Does a six-month defects period end every liability?

No such assumption is safe. Contractual defects procedures, retention release, warranties and other legal rights are distinct. Obtain advice on the current law and the wording for your project.

Can a clerk of works approve structural completion?

Only within their actual competence and appointment; the title alone does not confer engineering authority. Structural decisions and inspections must be assigned to the appropriately qualified and licensed professional.

Can video evidence replace an independent visit?

Not for inspections, tests or measurements that require physical professional verification. Use video to support communication, not to convert visible progress into an automatic payment certificate.

Download the transparent milestone-contract discussion template

Download GenZ Constructors' standard transparent milestone contract template.

The linked editable Markdown file is an educational discussion draft prepared for this guide, not confirmation of an existing lawyer-approved company standard, an executed contract or a ready-to-sign agreement. It includes fields for scope, stage values, inspections, certificates, retention, defects, variations and dispute procedures. Complete and reconcile it with a Kenyan advocate and the appointed professionals before use. If the hosted download becomes unavailable, contact GenZ Constructors for the current version.

The strongest payment system is not the one with the most reassuring label. It is the one that makes work measurable, independent verification practical, legitimate payment predictable and disagreements manageable. Put those controls in writing before the first major transfer.

This article provides general construction-planning information, not legal, financial, structural or tax advice, a guarantee of completion, or a statement that one contract form suits every project. Project-specific professional advice and currently applicable law take priority.