BBR as a Data Source: Areas, Use Codes, Verification

For most people, BBR (the Buildings & Dwellings Register) is the first lookup when a property needs to be valued, financed, insured or designed. It is free, covers virtually the entire building stock, and delivers a structured picture of what stands on the site. But the fields do not always mean what you immediately assume — an “area” is not just an area, and a use code is no guarantee of what the property is actually used for. Anyone who reads BBR at face value risks building their assessment on a figure that masks something other than what they think.

This guide uses BBR as a data source and gathers, in one place, what a professional needs: what the area concepts cover, how the use codes fit together, what construction and renovation years tell you — and, above all, how to verify building data against the other public registers, so the register becomes a foundation rather than a guess. It is written for those who make their living on precision: valuers, energy and building consultants, insurance professionals and engineers.

What BBR is — and what it is not

BBR describes the physical and technical conditions of sites, buildings, units (dwellings and commercial premises) and technical installations. It is a registration system, not an inspection system. The crucial — and often overlooked — point is that a large share of the information is reported by the owner and is not systematically checked after it is filed. BBR therefore tells you what was, at some point, registered about the property — not necessarily what stands on the site today.

That does not make the register useless — quite the opposite. As a structured starting point, BBR is unmatched. But it means every key figure should be treated as a claim that can be verified, not as an established fact. The fields professionals most often lean on are the areas, the use code, floor and roof conditions, construction and renovation years, and the technical installations. This is also where errors do the most damage, because they feed straight into a valuation, an insurance sum or a project assumption.

The most tangible version of the register is the BBR notice (BBR-meddelelse) — the printout the owner can pull, which typically forms part of a transaction. The notice is a reproduction of the register’s content at a given moment; it is not an independent confirmation that the content is correct. Read it as an overview of what needs to be verified, not as the final word.

Area concepts — the most common source of error

The single field that causes the most flawed valuations is the area — because BBR works with several area concepts that are not interchangeable and are easily confused.

• Footprint (bebygget areal) is the building’s footprint on the site — the area the building occupies seen from above. It is not the sum of the floors’ floor areas.
• Total building area / gross floor area (etageareal) sums the floors and is the figure that typically comes into play when the building rights on a site are assessed.
• Living area (and commercial area) is measured per unit and follows BBR’s own measurement rules for what counts — it is not the same as the “registered area” in the title or an agent’s “advertised area”.
• Heated area can differ from the living area because it is measured against a different criterion, and it is often the relevant figure in an energy context.
• Basement and attic area are treated separately, and a converted but incorrectly reported attic is a classic source of discrepancy.

The difference is not academic. For a valuer, it determines which area a price per square metre is multiplied by. For an energy consultant, it is the difference between whether the calculation hits the right heated volume. For an engineer or insurance professional, it is the difference between a correct rebuilding sum and one that is set too low. So always use the area concept that belongs to the task — and never mix them in the same calculation.

Rule of thumb: Before an area enters a calculation, clarify which BBR area concept it is — and whether it matches what the calculation requires. A figure without a concept is not a data source.

For the full walkthrough of each concept and how they differ, there is a deeper article on BBR areas: living area, heated area and footprint explained.

The use code — what it governs, and where it fails

The use code in BBR classifies what the building or unit is registered for — detached single-family house, terraced or semi-detached house, apartment block, office, shop, production, and so on. The code is not merely descriptive; it has real consequences. It feeds into property taxation, into what can be mortgaged, into insurance terms, and into how the property is handled for tax purposes.

The important thing to understand is the difference between two tracks that are often confused: the use code in BBR describes the actual, registered use, while the planning basis — the municipal plan framework and local plan in Plandata.dk (the national planning portal) — determines what the property may be used for. The two can be out of sync. A building can be registered as commercial but actually used as residential, or vice versa, without the code being corrected. And an actual use that conflicts with the local plan is not legalised simply because the BBR shows it.

For the professional segments reading this guide, the consequences are concrete:

• A wrong code can mean a property is valued or taxed on the wrong basis.
• A mismatch between code and actual use can trigger a legalisation case that a buyer inherits.
• For insurance, an imprecise use can mean the cover does not match the real risk.

The use code is therefore one of the fields that must always be cross-checked against both physical reality and the planning basis. A more detailed walkthrough of what the codes govern, and where they are typically wrong, can be found in the article on use codes in BBR and what they govern.

Construction year and renovation year — two fields that must be read together

The construction year is one of the most cited BBR fields and, at the same time, one of the most misunderstood if read in isolation. A construction year of 1952 tells you nothing about the property having been gut-renovated in 2018 — and for a valuation, energy or insurance assessment, that difference is decisive.

BBR therefore also contains fields for the renovation and extension year, and the two must be read together. The construction year gives the building’s original age; the renovation year can reveal a thorough overhaul that has genuinely changed the building’s condition, installations and lifespan. For a valuer, it shifts the starting point of the valuation. For an energy consultant, a renovation may have moved the building into entirely different technical premises. For an insurance assessment, a renovation changes the risk picture and the rebuilding cost.

At the same time, be aware that a renovation year — like the rest of the register — depends on someone having reported it. A renovation without a filing leaves no trace in BBR. That underlines the point: the years are entry points for asking the right questions, not final answers about the building’s real condition.

How to verify BBR against other registers

This is where a foundation differs from a guess. Verifying BBR means cross-checking the key fields against independent public sources — and treating discrepancies as a risk to be resolved rather than a figure to be ignored. The strongest cross-checks are all publicly available:

• Matriklen (the cadastre, maintained by the Agency for Data Supply) for the site’s real area and boundaries. The plot ratio is calculated from the site area in the cadastre, not from BBR — so the site area comes from here, not from the building register.
• Aerial and oblique imagery to see whether the building extent in the image matches the registered areas and the number of buildings on the site.
• Plandata.dk for the local plan and municipal plan framework that determine what the property may be used for — the central counterpart to BBR’s use code.
• Tingbogen (the Land Registry) for title, easements and burdens that can restrict use independently of what BBR shows.
• The energy label register for an independent picture of the building’s energy conditions and the heated area, which can be held up against BBR’s areas.
• The municipal building case archive to see whether renovations and extensions actually have a permit behind them.

The principle is simple: when the sources point in the same direction, you can trust the BBR figure. When they disagree — a photo showing more than the registered square metres, a use that conflicts with the local plan, a renovation year with no corresponding building case — you have found a discrepancy that must be resolved before it enters a valuation. The systematic version of this exercise, where BBR is held up against imagery, the cadastre and the building case, is described in cross-checking BBR against reality.

For a broader walkthrough of what BBR reliably shows, and where it typically goes wrong in a development context, there is also the article on BBR data in property development — what it shows and where it goes wrong. It is worth remembering that rules, measurement specifications and code meanings can change over time; when in doubt, they should always be verified in the current source or with the municipality.

A checklist for a solid BBR basis

Before a BBR figure enters a valuation, a calculation or an insurance sum, there are five questions that, in practice, decide whether the basis holds:

1. Which area concept is it — footprint, gross floor, living or heated area — and does it fit the task?
2. Does the use code match the actual use and the planning basis in Plandata.dk?
3. What do the construction and renovation years tell you together about the building’s real condition?
4. Do the registered areas match what imagery and the cadastre show?
5. Are renovations and extensions covered by a building case?

If all five hold, you have a data basis. If one of them wavers, you have found a risk — and it is often the one that decides whether a valuation is accurate.

From field to verified basis

The challenge with BBR is rarely that the information is hard to find. It is that it has to be read with the right definitions and held up against five other registers before it means anything. That cross-referencing is manual and time-consuming — and it is exactly what Arcili automates in the BBR tab of the Ejendomme (Properties) module: BBR’s areas, use codes and years are shown alongside the cadastre, planning basis, land registry and imagery, so the discrepancies leap out instead of hiding between the tabs. It does not remove the professional judgement — it gives it a verified starting point to build on.

Want to see a property’s building data held up against the other registers in a single view? Book a walkthrough.