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Assembling the preliminary file

📐 Focus5 min read

What you will learn The eight documents in the file, the collection order that saves time, what can be obtained free, and how to use it during and after the works.

A preliminary file is not an administrative formality. It is what turns an unknown building into a documented object, and therefore what reduces contingency before any investigation.

The eight documents

Document What it is for
Title documents establishing the position and history of the property
Cadastral record documenting official characteristics
Energy documents rating, year of construction, characteristics
Asbestos documents depending on region and year of construction
Electrical inspection condition and validity
Available drawings origin, alterations, earlier permits
Invoices for earlier works proof of installation and characteristics
Planning documents permits granted, any breaches

None of those documents is hard to obtain. Their absence stems from nobody asking for them at the right time.

The collection order

Four steps, from quickest to longest.

1. What the owner already holds. Documents handed over on acquisition, often complete and never reread.

2. What can be obtained from administrations. Cadastral record, earlier permits, planning information.

3. What exists but must be tracked down. Certificates still valid, inspection reports, invoices from firms that worked there.

4. What must be created. Missing surveys, measured surveys, investigations, which are the subject of the branch on surveys and preliminaries.

Starting with the fourth step is the common reflex and the costliest. Part of what one is about to commission already exists.

What is worth chasing

Three underestimated yet decisive documents. They govern the pricing and the tax eligibility.

Earlier permits. They document the authorised state of the property, which governs the regularity of what exists and the handling of any new application, covered in the article on permits and exemptions.

Invoices for earlier works. They prove characteristics that, absent proof, will be replaced by default values in energy documents.

Original drawings. Even approximate, they indicate the primitive structure and allow alterations to be identified.

What to check on each document

Three quick checks, applicable to every document. They bear on the date, the object and the author.

The date of issue, several documents having a limited validity.

The scope covered, notably where a property includes annexes or later extensions.

Correspondence with the actual property, a document possibly relating to a configuration predating alterations.

An expired or out-of-scope document is not a document. It gives false assurance, which is worse than absence.

Use during the works

The file does not serve only to prepare.

It serves as a reference when something is discovered, allowing what was documented to be distinguished from what was not, with direct effect on contractual treatment, covered in the article on discovery clauses.

It serves to settle interface disputes, by establishing the prior condition.

It serves to support grant applications, which generally require documents on the initial condition.

Use after the works

Three reasons to complete it rather than archive it. They relate to tax inspection, dispute and resale.

Documents on the works carried out will improve the next energy rating, as the article on energy assessments explains.

They will serve on resale, where the purchaser will ask for precisely those items.

They will serve if a defect arises, liability being capable of engagement several years after acceptance.

What this means for a professional

Three rules.

Ask for the file before the first technical visit, which directs investigation towards what is genuinely missing.

Flag expired or out-of-scope documents, rather than accepting them by default.

Hand the client a completed file at the end of the works, which has lasting value and distinguishes careful service.

This article reflects a professional method at the date of checking and serves as orientation. It does not replace technical advice or consultation of the competent administrations.

Frequently asked questions

The compulsory surveys, the property documents, the proofs of date and the planning papers. Four steps assemble it, from the quickest to the longest.

Three documents nonetheless govern the pricing and the tax eligibility. They are gathered before firms are consulted.

Through three quick checks on the date, the object and the author. They apply to every document in the file.

Yes, it serves as evidence during and after the works, notably on a tax inspection, in a dispute or on resale. That is why it is completed rather than archived.

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