The technical formalities of building tax incentives

Family	Content	Timing
Technical certifications	Attestations of compliance and of conformity with the requirements, where required	Before, during or at the end of the works depending on the case
Electronic notification	Transmission of data on works producing energy savings	Within the period running from completion of the works
Records to retain	Invoices, traceable payments, building consents and supporting documents	Built during the works, retained for the assessment periods

The three families follow different logics. The first two are active steps with a deadline: if the deadline passes, the step is omitted. The third is a retention obligation that only bites on an audit, but whose content cannot be reconstructed after the event.

Not every project requires a technical certification, and the first task is to establish whether one is required and which. The check is made against the rules of the deduction claimed.

Where required, the certification attests defined technical elements, typically that the works meet the requirements the relief imposes and, in some cases, that the expenditure incurred is reasonable. The content of the attestation varies with the situation.

Two elements matter for whoever gives it. They concern liability and the retention of supporting material.

The first is liability. A certification is a technical declaration with direct tax effects, and its untruthfulness produces consequences extending beyond the professional plane.

The second is retention of the supporting material. A certification is verifiable only if the professional retains the material it rests on, and tax assessment periods run longer than the period for which a practice ordinarily keeps site files.

Works producing energy savings require data to be transmitted electronically to the designated body, within a period running from completion of the works. The period runs from completion of the works and not from handover.

The deadline is the critical point. It is relatively short and runs from an event, completion, which in site practice does not always coincide with a formally recorded date.

The operational consequence is that the completion date must be fixed and documented, and that the step should be placed on the site closing checklist alongside final inspection and handover rather than treated as a subsequent formality. A missed deadline can be remedied only within the conditions provided.

This is the section where the work is done during the project or not at all. Some material can no longer be produced once the site closes.

The records to retain comprise invoices for the expenditure incurred, evidence of payments made by the traceable means required, the building consents or the substitute declaration on the start date of the works where no consent is required, and the supporting technical documentation. The set should be built progressively rather than at the end.

One element deserves isolating because it is the most frequent cause of disallowance on audit: payment must be made by means allowing the revenue administration to link the expenditure to the claimant and to the works. A payment correct in substance but made by non compliant means puts the deduction at risk, and it is an error made once and discovered years later.

The formalities are not uniform: they vary with the deduction claimed, and the most frequent error is applying the protocol of one situation to another. The protocol should therefore be checked for each deduction claimed.

Deduction	Typical formalities
Renovation deduction	Compliant traceable payment, retention of building consents and invoices
Energy efficiency deduction	The renovation formalities plus the electronic notification and, depending on the works, a technical certification
Seismic upgrade deduction	The renovation formalities plus the attestations proper to seismic classification
Furniture allowance	Traceable payment and a documentary link with the building works that make it available

The furniture row deserves a note. The deduction is conditional on renovation works existing, and the documentation must allow the link between the purchase and the works to be reconstructed, as well as compliance with the sequence of dates the rules require.

One general observation closes the picture: where several deductions apply to the same property, the formalities add up as well. There is no single protocol absorbing them, and the closing checklist should be built per deduction rather than per site.

The boundary of responsibility should be drawn precisely, because the subject is fiscal while the formalities are technical. The boundary is worth setting out in writing in the letter of engagement.

To the professional belong identifying which formalities apply, giving the certifications required, making the electronic transmission where instructed to do so, and producing the technical documentation. None of those activities includes assessing tax capacity.

To the client and their tax adviser belong checking the personal conditions, retaining the expenditure records and claiming the deduction in the tax return. The professional flags the point but does not replace the adviser.

The point that follows is contractual before it is technical: the appointment must say who does what. Much of the dispute between professional and client in this area arises from steps neither of them thought were theirs to take.

One final observation on timing. The steps described all fall at the closing of the site, which is the stage where attention drops and resources are already committed elsewhere. Building a standard closing checklist, with deadlines and owners, is the only measure that genuinely protects against omissions of this kind.