Bygningsreglementets vejledning om konstruktioner (BR18) – Danish Building Regulations Guidance for Structures
The Bygningsreglementets vejledning om konstruktioner is the official guidance document for Chapter 15 (§ 340 - § 357) of the Danish Building Regulations 2018 (BR18). Issued by the Danish Authority (Trafik-, Bygge- og Boligstyrelsen), this document establishes the regulatory framework for the design, execution, operation, and maintenance of building structures and components. It serves as a technical supplement to ensure compliance with the statutory requirements for structural safety, durability, and health within the Danish construction sector.
The guidance governs a wide range of regulatory domains, including general person safety, material suitability, foundation depth, and structural resistance to static and dynamic loads. It explicitly references the Eurocode system for structural design, including DS/EN 1990 (Eurocode 0) and material-specific standards for concrete, steel, timber, masonry, and aluminium. The scope includes traditional buildings, greenhouses, temporary structures such as tents and grandstands, and specialized installations like wind turbines. It also details the owner's legal obligations regarding the ongoing maintenance of elements such as balconies and large-span roof trusses.
This document incorporates a correction sheet (rettelsesblad) updated on January 24, 2024, specifically addressing the load-bearing capacity assessment of existing structures. The following sections detail the technical requirements for foundation depths, design loads, and maintenance protocols required under the Danish regulatory framework.
General Principles and Safety Levels
Section 340 defines the overarching safety level for persons in the built environment. All structural design and maintenance must ensure that no harm occurs to individuals or property on the site or neighboring plots. The document identifies four primary objectives:
- Person safety: Preventing injury from structural failure.
- Health protection: Ensuring structures do not pose health risks due to failure or instability.
- Durability: Achieving satisfactory functional and longevity standards.
- Pest prevention: Designing structures to prevent the intrusion of pests.
Section 341 requires that all building materials be documented as suitable for their specific purpose, considering their chemical and physical interactions within the building assembly.
Foundation and Frost Protection
According to § 342, foundations must be established at a frost-free depth and on load-bearing soil to prevent damage from ground movement. The guidance provides standardized depths for typical Danish soil conditions:
- Heated buildings: A minimum depth of 0.9 meters below ground level.
- Standalone foundations: A minimum depth of 1.2 meters below ground level.
- Alternative documentation: If foundations are placed shallower, it must be documented that ground temperatures will not fall below 0 °C or that movements will not cause damage.
Design Standards and Load Calculations
Structural design must follow § 344 and comply with Eurocode 0 – DS/EN 1990 and its associated Danish National Annex (DK NA). This framework applies to all load-bearing structures regardless of material.
- Material Eurocodes: Specific requirements for concrete, steel, timber, and masonry are found in §§ 345-351.
- Greenhouses: For heated greenhouses with automated snow-melting systems, snow load requirements may be reduced by 65% per § 344, stk. 3.
- Roof safety: Under § 343, roofs and skylights must be designed to prevent persons from falling through, especially during maintenance activities.
Temporary and Special Structures
Special regulations apply to structures not fully covered by standard Eurocodes. This includes glass structures, wind turbines, and transportable constructions.
- Wind turbines: Compliance is met by following Executive Order no. 651 of June 26, 2008, regarding technical approval schemes.
- Tents and stands: Tents must comply with DS/EN 13782, while telescopic stands and demountable grandstands must meet DS/EN 13200-5 and DS/EN 13200-6 standards.
- Glass structures: These are regulated under § 352 and must provide a safety level equivalent to other load-bearing elements.
Operation and Maintenance Obligations
Per § 357 and the Danish Building Act (Byggeloven) § 17, the building owner is legally responsible for maintaining the structure to ensure continued safety.
- Snow and water accumulation: Owners must clear snow and ensure drainage to prevent roof collapse, particularly on large-span halls.
- Balconies: Regular inspections are required to assess environmental exposure and structural integrity.
- Large-span trusses: Roof trusses with spans exceeding 12-14 meters typically require a specialized bracing project (afstivningsprojekt) to ensure overall stability.
- Moisture control: Owners must monitor structures for moisture to prevent weakened components and poor indoor climates.
Frequently Asked Questions
What is the standard frost-free foundation depth for heated buildings in Denmark?
According to the guidance for § 342, the standard frost-free depth for foundations under heated buildings is 0.9 meters below ground level.
Can snow load requirements be reduced for commercial greenhouses?
Yes, per § 344, stk. 3, snow load requirements can be reduced by 65% for heated greenhouses with automatic backup power for snow-melting systems.
Who is responsible for the maintenance of structural safety in a building?
The current owner of the building is responsible for ongoing maintenance and repairs to ensure structural safety under § 357 of BR18 and § 17 of the Building Act.
At what span width does a roof truss require a special bracing project?
A separate bracing project is typically required for roof trusses with a span exceeding 12-14 meters to ensure structural stability.
What standards govern the design of temporary tents and grandstands?
Tents must follow DS/EN 13782, while telescopic stands and grandstands must comply with DS/EN 13200-5 and DS/EN 13200-6.
Does the guidance cover safety against falling through roofs?
Yes, § 343 requires that roofs and skylights be designed with adequate safety to prevent persons from stepping or falling through during maintenance.
What load-bearing design framework is mandatory under BR18 Chapter 15?
Design must follow Eurocode 0 (DS/EN 1990) and the relevant Danish National Annexes (DK NA) for specific materials.
Are glass structures considered load-bearing under these regulations?
Per § 352, glass can be part of a load-bearing structure and must be documented to achieve the safety levels described in § 344.
