Faxing the UDAP: ABF Opinion & Heritage Works

Short answer: the architecte des Bâtiments de France (ABF — Architect of French Buildings) does not process your planning permission — the town hall does — but their opinion determines the decision as soon as the project is located within the surroundings of a listed historic monument, in a site patrimonial remarquable (SPR — remarkable heritage site), or in a classified or registered site. The unité départementale de l'architecture et du patrimoine (UDAP — Departmental Architecture and Heritage Unit), the branch of the DRAC (Regional Directorate of Cultural Affairs) that hosts the ABF, very commonly accepts by fax anything belonging to the technical file: missing façade photos, a colour chart reference, a joinery product sheet, a detail section, a site-visit report, a reply to a request for additional documents. Golden rule: state at the top the planning file number (DP or PC) issued by the town hall, the municipality and the exact address of the site, copy the town hall handling the application, and keep the transmission report — the only document capable of proving that the additional material was sent before the end of the one-month period the ABF has to reply.

Who decides what: the confusion that costs months

Many applicants think they are "filing an application with the ABF". That is never the case for a private individual. The process runs as follows:

1. You file your déclaration préalable (DP — prior declaration of works) or your permis de construire (PC — building permit) with the town hall of the place where the works will take place.
2. The planning department notes that the site falls within a protected perimeter and forwards the file to the UDAP for an opinion.
3. The ABF issues a simple opinion (advisory) or an approval (binding, with conditions where applicable), depending on the nature of the protection.
4. The town hall takes over and signs the decision, incorporating the ABF's conditions.

Practical consequence: a fax sent to the UDAP without a planning file reference goes nowhere, because the officer has no way of knowing which pending file to attach it to. Conversely, a fax sent only to the town hall when the ABF is waiting for a document risks never reaching the right desk before the deadline.

The rule to remember: write to the UDAP and copy the town hall, or the other way round — but never just one of the two.

The three protection regimes, and what they change

This distinction between a simple opinion and an approval is the most useful thing to check before writing anything at all: it determines whether your arguments need to convince the ABF or the town hall. The Code du patrimoine (Heritage Code) and the Code de l'urbanisme (Planning Code) govern these regimes; your region's DRAC portal and the Ministry of Culture website publish the perimeter maps, and the Géoportail de l'urbanisme (national planning geoportal) lets you check whether the plot is actually concerned.

Why the fax remains useful when dealing with a UDAP

UDAPs are small services — often three to eight staff for an entire department — handling several thousand opinions a year. They work with a generic email address, sometimes overflowing, and a telephone switchboard open a few half-days a week. In that context, the fax keeps three concrete advantages.

It produces a time-stamped record. The ABF has one month (two months for a building permit in certain cases, with specific deadlines for classified sites) from the receipt of the file by the UDAP. Once that period has passed, their silence amounts to tacit approval in several configurations. In other words: days count, and a document arriving the day after the deadline can turn an approval into a refusal. The fax transmission report, which states the number dialled, the date, the time and the number of pages, is the evidence you will produce if the administration disputes the date of sending.

It gets around oversized attachments. A façade drawing scanned at high resolution, a materials statement and ten photos quickly add up to 40 MB — beyond what a public mailbox will accept. The fax, for its part, splits the document into pages and knows no size limit, only a legibility limit.

It lands in a physical place. In small services, the fax comes out on paper and ends up on the desk of the case officer, who staples it to the file. It is rudimentary, but formidably effective when the alternative is an email drowned among four hundred messages.

For everything concerning the legibility of the document on arrival — contrast, resolution, orientation — our guide on preparing a PDF that faxes well details the settings to apply before sending. This matters all the more here because the ABF judges on appearance: a colour sample that comes out dark grey instead of "Basque red" is of no use at all.

What works by fax, and what does not

What the UDAP handles by fax without trouble

• The reply to a request for additional documents from the UDAP or relayed by the town hall.
• Photographs of the existing building: the whole façade, joinery detail, view of the urban context, view from public space (the ones the ABF systematically asks for when they are missing).
• A descriptive statement of materials: species and section of timber, type of render, finish, method of installation.
• Manufacturer technical sheets for a roof tile, a zinc gutter, low-emissivity glazing, a hinged shutter.
• A colour reference: RAL code, colour chart reference, sample photographed next to a colour reference chart.
• A detail sketch: cornice profile, glazing bar section, junction between two materials.
• The report of a site visit or written confirmation of a telephone conversation with the architect.
• A request for an appointment before filing, with a brief description of the project.

What does not work, or works badly

• The initial filing of the DP or the PC: it is done at the town hall (counter, registered post or online service), never at the UDAP.
• Scale drawings intended to be measured: a fax distorts slightly and guarantees no scale. Send the drawing by fax to inform, and the original by post or in person.
• Documents where colour is critical: a colour chart, a photo of stone, a landscape montage lose the essentials. Fax the written note with the colour code and send the physical sample by post.
• Legal proceedings against a refusal: that falls to the administrative court, with its own rules (see our article on the admissibility of an appeal by fax before the administrative court).
• The preliminary administrative appeal before the regional prefect against a refusal of ABF approval: it is addressed to the regional prefecture, within a short deadline, and deserves registered post in addition to the fax.

Putting together a submission that holds up

The cover sheet, first of all

It is what makes the difference between a filed fax and a lost one. It must bear, at the top and legibly:

• Recipient: "UDAP of [department] — for the attention of the Architect of French Buildings in charge of the [municipality] sector".
• Subject: "File DP 0XX XXX 26 X0XXX — [address of the site] — transmission of additional documents".
• The applicant's name exactly as it appears on the planning form (a single mistake in the name is enough to break the link with the file).
• The copy notice: "Copy: planning department of the town hall of [municipality]".
• The number of pages and a means of calling back: telephone and email.

Our fax cover sheet generator produces this block in a few clicks, and the article devoted to the cover sheet template that stands as proof explains why some entries matter more than others.

Photos: the weak point of 80% of applications

The ABF does not visit every plot. They judge on what you show them. Refusals and requests for further documents overwhelmingly concern photographs that are missing, blurred, framed too tightly or taken against the light.

A few habits that change everything:

• Photograph in diffuse light, never in low raking sunlight, and head-on rather than at an angle.
• Show the context: the neighbouring façade, the street, the roof in its setting. The ABF thinks in terms of the whole, not an isolated object.
• For joinery or moulding details, place a tape measure in the frame to give scale. A simple builder's tape measure is enough, and it avoids back-and-forth over dimensions.
• Date each view and number the shots on a location plan.
• Print the photos on matte photo paper rather than glossy: matte reproduces better on both scanner and fax, whereas glossy reflects and creates white veils.

When the project concerns colour — shutters, joinery, render, ironwork — nothing beats a RAL paint colour chart bought once and for all: you give a code, the ABF replies with a code, and nobody argues any further about the exact shade of "carriage green".

Assembling a single document, in the right order

A file split into six separate transmissions is a file that gets lost. Assemble everything into a single PDF: cover sheet, a one-page letter, the schedule of documents, then the documents numbered in the order of the schedule. Our PDF file assembly tool does this job with no software to install.

If you scan a lot of large-format documents, an A3 flatbed scanner makes the exercise far more comfortable than handheld photography, especially for façade surveys and old drawings that you will sometimes be asked to attach exactly as they are.

Deadlines: what runs, and from when

The most misunderstood point is the starting date. The ABF's deadline runs from the receipt of the file by the UDAP, not from your filing at the town hall. Between the two, one to three weeks can go by, depending on how fast the municipality forwards it.

What to take from this:

• Call the town hall about ten days after filing to find out whether the file has gone to the UDAP, and on what date. Note the date and the name of the person you spoke to.
• If the UDAP asks you for a document, do not drag your feet: such a request rarely suspends or extends the deadline in a comfortable way, and an incomplete file frequently ends in an unfavourable opinion "as it stands".
• In the event of an unfavourable opinion, the town hall refuses if that opinion was an approval. You can then file a new, modified application — often faster and more effective than litigation — after an appointment with the ABF.
• Bear in mind that your planning permission has its own deadlines (one month for a DP, two or three months for a PC), set out in our article on building permit deadlines you must not miss.

For a project in a protected area, keeping an A4 lever arch file per application — with fax transmission reports, letters received, dated photos — is not bureaucracy: it is what allows you, eighteen months later, to prove that the condition was complied with during the conformity check.

Finding the right fax number

There is no single "ABF" number: each UDAP is departmental, and its fax number appears on the letterhead of the correspondence it sends, in the directory of your region's DRAC (Ministry of Culture website) and in the administration directory on service-public.fr. The number printed on a letter you have received is always the most reliable source: it has been updated by the service itself.

Before sending, two checks are worth ten minutes:

• Compare the number against two different sources, as explained in our guide to finding and verifying a French government fax number.
• Check that it really is the UDAP and not the regional DRAC: the regional DRAC handles authorisations relating to listed monuments themselves and to classified sites, not day-to-day opinions on monument surroundings.

If you do not have a fax machine, sending from a computer or a phone via our fax sending form does exactly the same job, with a downloadable transmission report. And if the file is bulky or the connection poor, the local solutions listed in where to send a fax without a fax machine in France remain useful.

One last detail that saves applications: if your project concerns a property whose exact heritage status you do not know, a practical planning guide or a book on the restoration of old buildings will stop you proposing materials that will be rejected out of hand — PVC in an SPR, machine-made tiles on a slate roof, cement render on a soft stone wall.

Frequently asked questions

Can a prior declaration of works be filed directly with the UDAP by fax?

No. Filing is done at the town hall, or through the municipality's online planning service. The UDAP is only called upon by the town hall. An application faxed directly to the UDAP will not be registered as a filing and will not start any deadline running.

Can the ABF impose a colour or a material on me?

When its opinion is an approval (surroundings of a listed historic monument, remarkable heritage site), it may attach conditions that the town hall incorporates into the decision. They then become mandatory and can be checked on completion of the works. In a registered site, the opinion is a simple one: the town hall may depart from it, but rarely does.

What should I do if the ABF has issued an unfavourable opinion?

Three routes, in this common-sense order: ask the UDAP for an appointment to understand what the obstacle is and refile a modified application; lodge an administrative appeal before the regional prefect against the refusal of approval, within the deadline stated on the decision; bring proceedings before the administrative court against the town hall's refusal decision. In the last two cases, registered post is essential, with the fax serving only as a fast duplicate.

Does silence from the ABF amount to approval?

In several configurations, yes: the absence of a reply within the allotted period amounts to tacit approval, and the town hall may issue the permission. But the deadline starts from receipt by the UDAP, not from your filing — all the more reason to have the town hall make a note of that date.

Should a fax be backed up with registered post?

For a simple technical addition (photos, product sheet), no: the transmission report is enough, especially if you copy the town hall. For anything involving an appeal deadline or a formal challenge, yes — registered post with acknowledgement of receipt remains the benchmark, with the fax used to gain the few days you are short of.

How long should transmission reports be kept?

At the very least until the déclaration attestant l'achèvement et la conformité des travaux (DAACT — declaration certifying the completion and conformity of the works) and the expiry of the municipality's inspection period, i.e. three to five years after the end of the works depending on the case. In a protected area, keep them with the building file: they document the choices that were approved.

In summary

• The UDAP hosts the Architect of French Buildings; it issues an opinion on your application, it does not process it and does not receive the initial filing.
• The protection regime (surroundings of a listed historic monument, SPR, classified or registered site) determines whether the opinion is a binding approval or a simple opinion — check it on the Géoportail de l'urbanisme (national planning geoportal) before writing.
• The fax is perfect for supporting material: photos, materials statement, technical sheets, colour codes, detail sketches, appointment requests.
• It replaces neither the filing at the town hall, nor sending the scale drawings, nor registered post for an appeal.
• Always restate the planning file number, the municipality and the address of the site, and copy the town hall.
• The one-month deadline runs from receipt by the UDAP: have the town hall note that date and keep every transmission report until the conformity check.