How do you capture additional and omitted works and communicate changes during a construction project?

What are additional and omitted works during a construction project?

Additional and omitted works concern changes to the agreed work: something is added, something is removed or the construction method changes. Start with the original agreement. An extra activity on site is not automatically a chargeable change instructed by the client.

Examples include an extra connection point, a different finish or an omitted cupboard. First investigate whether the work is already included in the instruction, why it is changing and which agreements apply to the change. Correcting your own error and an additional client request are different triggers; do not group them together without assessment.

Keep the request, work and processing separate

Omitted works belong in this process too. Record which element is removed, which work needs to stop and which implications are still being assessed. Removing an element does not automatically cancel every previously ordered quantity, preparation activity or price agreement in full. Have the person responsible determine contractual and financial processing.

How do you identify and communicate a change?

Report the difference as soon as it becomes clear, within the right project and to the person who needs to assess the implications. A photo with ‘this needs changing’ does not show the original instruction, who is requesting the change or which decision is needed.

Use one change reference

Give the change a consistent reference, such as W-014, and use it in conversations, actions, documents and administration. Let the team or the system used for that purpose determine the reference. This is not a claim that Woub automatically assigns such numbers.

Use the information below to track the change. In Woub, communication is kept within the project. For supported calls and recorded live meetings, Wouby AI automatically creates a subject, summary and tasks from the recording. You do not need to retype that conversation outcome in a separate form. The third column shows where Woub helps and which information you need to provide yourself.

A change can affect several businesses. If the client wants a different construction method, the subcontractor also needs the right instruction. Their original instruction does not change simply because the main contractor posts an internal message.

What the Fuhler case adds

The Fuhler Wegenbouw customer story specifically describes recording additional works and agreements with site inspectors as a communication issue. The case shows how text, photos and retrievable project information support the handover.

That customer experience supports the practical need. It does not prove every site inspector may approve extra costs on behalf of a client, or that recorded work is automatically invoiceable. Keep source, authority and financial processing separately identifiable.

Who needs to approve changes formally?

That follows from the contract and authority arrangements within the project. The person passing on a request, receiving a photo or supervising on site is not automatically authorised to instruct changed work and extra costs.

Decide beforehand who makes decisions on behalf of the client and contractor. Also check who may instruct a subcontractor. Make clear what a confirmation covers: the technical solution, price agreement, time for carrying out the work, or just an instruction to investigate something.

A working agreement is different from permission for a price increase

De Hoge Raad addressed this distinction on 1 July 2022. For changes requested by the client, the rule discussed in the judgment requires a timely warning of the need for a price increase, unless the client should have understood that need themselves. Consent to additional works therefore does not necessarily mean agreement to a higher price.

The judgment also makes clear that an exact amount fixed in advance is not the same legal requirement in every situation; where no price has been fixed, a reasonable price may apply. Do not turn an internal ‘confirm the price first’ agreement into a general assertion that other work never needs to be paid for.

For daily organisation, it remains sensible to deal with scope, price agreement and conditions as clearly as possible before carrying out the work. Follow the contractual process and have the person responsible for the contract assess uncertainty over authority, warnings or adjustments. A status in an app does not decide this independently.

How do you record action items and site agreements?

For each change, make clear which next action is needed and what may already be carried out. A task to calculate a price is different from an instruction to start the work. Link both to the same reference.

For example, write: ‘Construction project coordinator asks the installer to work out the implications of W-014 and presents the outcome to the project manager.’ Add when feedback is needed. If the conversation lacks that deadline, agree it rather than presenting it afterwards as an agreed date.

For supported conversations through Woub, Wouby AI can automatically record recognised commitments as tasks. Check content, person responsible and deadline. The task does not independently authorise extra costs, a changed subcontractor instruction or carrying out the work.

Also communicate a withdrawn or superseded instruction

With a new version of the change, make clear which earlier instruction is superseded. Inform those already ordering materials, preparing work or planning site activities. An updated agreement has little value if the buyer is still working from the previous version.

For drawings and models, refer to the current source and revision. Use a project chat for daily coordination; keep formal document status in the designated DMS or BIM environment.

How does Woub help prevent completed additional works being forgotten at invoicing?

Create a checklist within the project in Woub with tasks that support the person invoicing. This gives the handover from completed additional works to administration a consistent place: the site manager reports what is complete, the project manager checks the agreements, and the person invoicing processes the outcome in ERP or another financial system. The checklist helps follow up those steps alongside conversations, photos and agreements within the project.

Example: additional works ready for invoicing checklist

The checklist below is an example you can set up yourself in Woub and adapt to your invoicing cycle:

1. Site team — report completed work: state the change reference, what was carried out and any photos or quantities.

2. Project management — check the agreement: check which scope and payment have been confirmed and which points remain open.

3. Invoicing — check the financial record: find the change in ERP or the financial system and check whether it has already been processed or invoiced.

4. Invoicing — include invoiceable additional works: process them in the financial system under the agreed pricing and invoicing conditions.

5. Invoicing — report back on processing: update the related task in Woub and state the financial reference or what is still missing.

Think of extra fencing installed on request. The site manager posts the completion report with a photo within the project. Through the checklist, the person invoicing receives a task to check the confirmed additional works agreement and include it in the invoicing cycle. If price confirmation is still missing, that remains a clearly identified outstanding point for the project manager.

This is specifically how Woub works alongside ERP: Woub supports communication and handover tasks; ERP or the financial system handles the financial record and invoice. You configure the checklist yourself. It does not mean Woub automatically checks invoices or synchronises tasks with the financial system.

Small business without ERP? Record hours and materials within the project

If you run a small construction company without ERP, you can use the Woub add-on Uren & materialen to record resources used for additional works within the project. Employees record their hours worked and materials used; administrators view the overview. The person invoicing then has the recorded resources alongside the agreement.

Example: an installer carries out an extra element. They record hours and materials within the project and state your change reference in a note. The checklist task helps the colleague invoicing compare this with the confirmed additional works agreement.

You can configure hour types with rates and materials with units and prices. Records can be filtered and exported; a PDF hours and materials overview can include notes and prices. Use this for invoice preparation and check which resources are invoiceable under the agreement. You create the invoice in your financial system.

The add-on supports recording; it does not automatically establish what has been approved as additional works. AI task creation also does not mean hours and materials have automatically been recorded. See the guide and settings for Uren & materialen.

Check more than just ‘complete’

Record a focused follow-up action for each outstanding point. Do not mark a site action as financially settled because there is a photo of the result. And do not call work forgotten revenue before establishing the financial agreement and entitlement.

Choose a review point that fits the agreed invoicing cycle. A business invoicing in instalments has different processing from one working on a time-and-materials basis. The aim is to keep outstanding changes recognisable, even when they do not yet belong on an invoice.

What does the process look like with Woub alongside ERP?

Let ERP handle financial recording and processing. Woub supports complementary conversations and actions around the change. Use the same reference to connect the request, approval, site instruction and administrative record.

This is a proposed process, rather than a description of an existing automatic Woub integration. For a desired integration, check which data is actually exchanged, in which direction and who resolves an error.

At 1–10 employees, one person may handle several steps; at least show which role they are performing at that moment and who covers for them. With 10–100 employees, the handover between site teams, project preparation and administration becomes more important. With 100+ employees, authority arrangements between teams, checks and exceptions also need a regular owner. Headcount does not change the contractual agreement.

For the broader division of responsibilities, read Woub alongside ERP software.

When do you record additional works directly in ERP instead of Woub?

Record financial data directly in ERP if that is the designated place for pricing, additional works records, budget monitoring and invoicing. Do not create a competing financial list in Woub for the same data.

ERP may itself support communication and mobile recording too. The official Exact voor Bouw feature page describes additional and omitted works records, invoicing, budget breakdowns and communication with the client, for example. What you use depends on the package and setup. Woub is only complementary if daily coordination and follow-up remain that it can organise better.

If the change request is already complete in ERP, share the relevant question or instruction in project communication with a reference to that record. Do not copy all amounts again if the site manager only needs to know the confirmed work.

If it concerns a buyer's choice for a particular plot number, also retain the agreed choice and status in the property handover file. Read how to use Woub alongside property handover file software without creating a second version of the truth about buyers' choices.

What is a practical example from change to invoice?

Suppose a client requests an extra connection point during an alteration project and removes an element chosen earlier. This is an illustrative process example, rather than a customer case or a judgment on whether the particular work is chargeable.

1. Request: the site manager records both changes under one recognisable change reference, with location and source.

2. Development: the construction project coordinator has the installer describe the extra work and also checks the implications of the omitted element. If materials have already been ordered for it, that is assessed separately.

3. Decision: the person responsible for the project has the instruction, price agreement and conditions handled through the agreed route. The changed instruction to the installer is also confirmed.

4. Recording: administration enters the financial agreement in ERP. Communication uses the same reference.

5. Site work: the installer receives the current instruction and reports the extra work complete. The crew also knows which element is no longer being carried out.

6. Processing: before the relevant invoicing cycle, project management and administration compare the work with the record. An outstanding adjustment remains visible; an already processed item is not invoiced again.

Test this route with a real change. Can a colleague who was not in the first conversation find what was requested, who decided, which instruction applies and which financial step remains open?

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