Is the Building Decree 2012 still in force?

No. The Building Decree 2012 was replaced as of 1 January 2024 by the Dutch Building Decree (Bbl, Besluit bouwwerken leefomgeving) under the Environment and Planning Act. In substance, the Bbl is largely identical to the former Building Decree, with a few additions in the area of energy and circularity. The NEN standards to which the Bbl refers have for the most part remained unchanged.

Which topics does the Bbl cover?

The Bbl consists of six main categories: 1) Structural safety (strength of the building structure according to NEN-EN 1991-1999), 2) Fire safety (compartmentation, escape routes, fire classes according to NEN 6068, NEN 6069), 3) Health (ventilation, daylight, sound, moisture according to NEN 1087, NEN 5077, NEN 2057), 4) Usability (clear height, door openings, accessibility), 5) Energy efficiency (Rc values, BENG assessment according to NTA 8800), 6) Environment (waste, asbestos, choice of materials).

What are the minimum Rc values?

The Bbl prescribes minimum Rc values for insulation: floor Rc 3,5 m²K/W, facade Rc 4,7 m²K/W, roof Rc 6,3 m²K/W. For BENG-compliant building, the practical values are higher: floor 4,5, facade 6,3, roof 6,5. For window frames, a U value of no more than 1,65 W/m²K applies for regular double glazing, or better 0,7-1,1 for triple glazing in BENG-compliant homes.

What is fire compartmentation?

Fire compartmentation is the division of a building into independent fire zones by fire-resistant walls, floors, and doors. The aim is that fire cannot spread to adjacent zones within 30 or 60 minutes. For homes, every living space must be a separate fire compartment. For apartments, the additional requirement is that stairwells and corridors must be closed off in a fire-resistant manner. A common specification is 60 minutes of fire resistance for partition walls.

Who assesses the Bbl?

During the application for the environmental permit, the municipality assesses whether the submitted drawings and calculations comply with the Bbl. Since the Building Quality Assurance Act (Wet kwaliteitsborging voor het bouwen, Wkb) of 2024, an external quality assurer is additionally mandatory for residential projects in consequence class 1, assessing during and after construction whether the actual execution complies. The quality assurer is hired by the owner and submits a completion notification to the municipality.

What is consequence class 1?

Consequence class 1 covers most regular residential projects: single-family homes up to three storeys, small apartment buildings, and non-public commercial buildings below certain limits. For this category, the Wkb quality-assurer obligation applies. Consequence classes 2 and 3 cover larger buildings, hospitals, schools, and shopping centres, for which stricter assessment applies. The Wkb is being introduced in phases; consequence class 1 has been mandatory since 2024, higher classes follow in 2026-2027.

Does the Bbl also apply to renovation?

Yes, in part. For renovation or conversion, the Bbl applies to the new or altered parts, but not to the existing part that remains unchanged. An extension must comply with the current Bbl standards for insulation, ventilation, and structural safety, even though the existing home (from 1960, for example) does not meet the current standards. For home splitting, the rule is that the new dwelling units must fully comply with the Bbl, including a BENG calculation.

What if I do not comply with the Bbl?

In the case of non-compliance, the municipality refuses the environmental permit. In the handling phase, you receive a completion request with specific points where the design must be adjusted. This may involve: thicker insulation, replacing window frames, increasing the fire resistance of walls, or adjusting the ventilation flow rate. After adjustment, the application is reassessed. In the case of continued non-compliance, the municipality may ultimately refuse, and a new application with the adjusted design must be submitted.

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Permits

Building Decree / Bbl 2026: what it says and how you are assessed

Snel Kwaliteit Tekenwerk6 May 20267 min read

3D illustration of an adviser reviewing the Dutch building decree next to a wooden house model, with a green checkmark.

Since 1 January 2024, the Building Decree has been replaced by the Dutch Building Decree (Bbl, Besluit bouwwerken leefomgeving) under the new Environment and Planning Act (Omgevingswet). The Bbl contains all technical building requirements for the Netherlands: structural safety, fire safety, health, usability, energy, and environment. For regular residential projects such as an extension or dormer, the assessment covers structural safety (NEN-EN 1990 series), fire compartmentation (NEN 6068), thermal insulation (Rc values), and ventilation (NEN 1087). The municipality assesses the Bbl during the handling of the environmental permit. For permit-free building, the Bbl still applies but is not checked in advance by the municipality.

History: from the Building Decree to the Bbl

Dutch building regulations have a long history. The original Building Decree (Bouwbesluit) dates from 1992 and has been amended several times since. The major step in 2003 introduced the structure conforming to the European directive. The Building Decree 2012 was the most widely used version and contained the technical requirements for all structures in the Netherlands. As of 1 January 2024, the Building Decree 2012 was replaced by the Dutch Building Decree (Bbl, Besluit bouwwerken leefomgeving) under the new Environment and Planning Act (Omgevingswet). In substance, the Bbl is 90 percent identical to the former Building Decree, but the structure has been revised to align with the systematics of the Environment and Planning Act. The NEN standards to which the Bbl refers have for the most part remained unchanged, so that experienced building draughtsmen and architects can continue to work without problems on the basis of their existing knowledge. The text of the Bbl is publicly available via wetten.overheid.nl and is updated annually by the Ministry of the Interior and Kingdom Relations.

The six main categories

The Bbl is divided into six main categories of technical requirements. Category 1, Structural safety: this covers the strength, stiffness, and stability of the structure according to the NEN-EN 1990 series ("Eurocodes"). NEN-EN 1991 covers loads on structures including permanent weight, snow, and wind. NEN-EN 1992 covers concrete, NEN-EN 1993 steel, NEN-EN 1995 timber, NEN-EN 1996 masonry, NEN-EN 1999 aluminium. Category 2, Fire safety: fire compartmentation, escape routes, fire resistance of building components, and fire classes of materials according to NEN 6068, NEN 6069, and EN 13501. Category 3, Health: ventilation according to NEN 1087, daylight according to NEN 2057, sound insulation according to NEN 5077, and moisture resistance. Category 4, Usability: a minimum clear passage height of 2,1 metres for homes, door openings of at least 850 mm, and accessibility for people with a disability according to NEN 1814. Category 5, Energy efficiency: minimum insulation Rc values, U values of window frames, and BENG assessment for new build and major renovations according to NTA 8800. Category 6, Environment: waste streams during construction, asbestos policy, and choice of materials in relation to circularity.

Structural safety in detail

For most residential projects, the structural-safety assessment is the focal point of the Bbl assessment. According to NEN-EN 1990, all building structures must satisfy two limit states: the ultimate limit state (in which the structure must not collapse) and the serviceability limit state (in which deformation and deflection remain limited to acceptable values). For a dormer addition, it is assessed whether the existing roof structure can bear the extra load of the dormer plus the dormer window plus any interior fittings. For an extension, it is assessed whether the existing facade opening can be cut out without weakening the main load-bearing structure, and whether the new gutter extension satisfies stability requirements. For a roof addition, it is assessed whether the existing building can bear an extra storey, often with an additional steel or concrete structure. The structural calculation according to the NEN-EN series is a mandatory part of the permit file for projects with structural impact.

Fire compartmentation and escape routes

Fire safety is the second major category. The Bbl requires that a building be divided into fire compartments, that is, independent fire zones separated by fire-resistant structural components. For homes, every living space is a separate fire compartment. For apartments, each apartment forms a separate compartment, and the corridors and stairwells together form the escape compartment. Fire resistance is expressed in minutes: 30 minutes (REI 30), 60 minutes (REI 60), or 90 minutes (REI 90). For homes, REI 60 is standard for partition walls between dwelling units, REI 30 for internal partition walls within a home, and REI 90 for the load-bearing structure. Escape routes must satisfy the main rule "two independent escape routes from every habitable room" or, in the case of single-sided access, a short escape route of no more than 30 metres to a safe outdoor space. The fire class of materials is classified according to EN 13501-1 into seven classes from A1 (non-combustible) to F (highly combustible). For the facade of a home, class B s2 d0 is generally required.

Energy and BENG relationships

Energy efficiency has become more dominant in the Bbl since 2021. For new build and major renovations, BENG assessment according to NTA 8800 is mandatory. BENG consists of three indicators: BENG 1 maximum energy demand, BENG 2 maximum primary fossil energy, BENG 3 minimum share of renewable energy. For regular extensions and rear extensions under 25 percent of the building envelope, BENG is not mandatory, but the minimum Rc values do apply: floor 3,5, facade 4,7, roof 6,3 m²K/W. For BENG-compliant building, practical values are higher, at floor 4,5, facade 6,3, roof 6,5. Window frames must have a U value of no more than 1,65 W/m²K for double glazing; in BENG-compliant homes, triple glazing with a U value of 0,7-1,1 is often applied. In addition to envelope insulation, the Bbl requires a minimum ventilation flow rate according to NEN 1087: 0,9 dm³/s/m² for living rooms, 0,7 dm³/s/m² for bedrooms, 1,4 dm³/s/m² for kitchens. A BENG-compliant home combines these with heat recovery, which keeps energy loss through ventilation to a minimum.

The Wkb and quality assurers

Since 1 January 2024, in addition to the Bbl assessment by the municipality, an external quality assurer is also mandatory for residential projects in consequence class 1. The Building Quality Assurance Act (Wet kwaliteitsborging voor het bouwen, Wkb) shifts part of the building assessment from the municipality to private quality assurers. The quality assurer is a party accredited by the Admissions Body for Building Quality Assurance (TLB, Toelatingsorganisatie Kwaliteitsborging Bouw) that assesses, before, during, and after construction, whether the actual execution complies with the Bbl. The municipality assesses only the application at a high level; the detailed assessment runs via the quality assurer. On completion, the quality assurer submits a completion notification to the municipality showing that the structure has been completed in accordance with the Bbl requirements. Only after this completion notification may the structure be put into use. The quality assurer is hired by the owner and costs an average of €1.500 to €3.500 for a single-family home depending on complexity. The Wkb has been introduced in phases: consequence class 1 has been mandatory since 2024, consequence class 2 (larger buildings) follows in 2026-2027.