Do you need a permit for a steel shed or hall in Belgium, the Netherlands or Luxembourg?
Updated on 24 October 2026
The principle, region by region
An industrial hall, agricultural building or storage building usually needs a prior step: depending on the project and the region, a permit, a notification or an exemption under conditions. The exemptions mostly cover small outbuildings next to a home, such as a carport or a shelter, and a few light agricultural structures. In Wallonia, a specific heading rules out using another heading [1]. Zoning and local rules can restrict the exemptions.
| Region | Framework | Exempt small structure | Hall or agricultural shed | Architect |
|---|---|---|---|---|
| Wallonia | CoDT, permis d'urbanisme | Carport: 40 m², 2.50 m to the eaves, 3.50 m to the ridge [1]. Business outbuilding: 75 m² [1] | Permit required. No conventional agricultural shed in the exemption list [1] | Mandatory for a hall that needs a permit, subject to the nomenclature [1] |
| Flanders | Omgevingsvergunning, vrijstellingenbesluit | Detached outbuilding or carport: 40 m² per property, 3.5 m high [2] | Permit required for enclosed buildings. Industrial: 100 m² maximum under conditions [2] | Exemption up to 40 m² (eaves 3 m, ridge 4.50 m). No hall in the list [3][4] |
| Brussels | CoBAT | Isolated accessory building: 9 m², 3.00 m high, courtyards and gardens zone [5] | Permit required above 9 m² [5] | Federal law of 1939: the exemptions we read do not cover halls [12] |
| Netherlands | Omgevingswet, Bbl, Wkb | No hall or shed in the Bbl list of permit-free work [8] | Not in the permit-free list [8]. Planning track under the omgevingsplan, technical track by permit or Wkb notification depending on classification [7][8]: to be verified | Not required by Dutch law: to be verified |
| Luxembourg | Autorisation de bâtir, PAG, PAP | The commune may exempt small works in its building regulations [9] | Autorisation de bâtir. In the green zone, the Minister of the Environment must also authorise [9][10] | Only an architect may draw up the plans (page for private individuals). The same page cites a cost threshold of 6,197.34 euros excl. VAT for a private person building for their own use. Its exact scope (exemption from the architect or not) is to be verified [9] |
Rules change. The thresholds in the table come from texts consulted on 24 October 2026, some dating from 2021 (Wallonia). The commune or the competent authority decides for your plot. This guide is not legal advice.
Wallonia (CoDT)
The nomenclature of article R.IV.1-1 of the CoDT lists the exempt works. The version we read is updated to the 2021 decrees. The thresholds may have changed since, to be verified on Wallex or the territory portal [1].
- Carport: exempt if it is the only one on the property, directly linked to the access road, not beyond the rear elevation plane of the main building, no more than 40 m², 2.50 m to the eaves, 3.50 m to the ridge, with timber, concrete or metal posts [1].
- A carport that does not meet these conditions falls under the limited-impact permit, without an architect [1].
- Economic activity: a non-residential building linked to an existing business, in an economic activity zone, within 30 m of the main building and at least 3 m from the boundaries, is exempt from permit and architect up to 75 m² [1].
- Farm: the list mentions buried silos, manure slabs, tanks and removable polytunnels. No conventional agricultural shed appears in it, so a shed needs a planning permit, to be confirmed in the current version [1].
- A permit exemption does not release you from the Civil Code, the Rural Code or the PEB energy decree. Distances to watercourses and setback zones still apply [1].
Flanders (omgevingsvergunning)
The vrijstellingenbesluit of 16 July 2010 sets the exemptions. We read the consolidated version of the Codex Vlaanderen in force on the day of consultation. Its articles have applied since 1 March 2026 or 5 September 2026, depending on the article [2].
| Case | Main conditions | Article |
|---|---|---|
| Home outbuilding or detached carport | 40 m² in total per property, including all existing detached outbuildings. Maximum height 3.5 m. Distance to the boundary: 3 m in the side zone, 1 m in the rear garden. Rainwater not drained off the plot. 30 m radius around the house [2] | 2.1, 11° and 2.2 |
| Industrial zone, new building | Link with the existing business. Less than 30 m from a permitted building. 100 m² per project zone (500 m² in a delimited seaport zone) and at most 100 per cent of the area already permitted. One storey, 10 m high, fire load below 350 MJ/m², 5 m from boundaries, 30 m from a residential zone [2] | 4.3 |
| Agriculture, structure that is not a building | Within 30 m of a permitted agricultural building, up to 100 m² per property and 10 m high [2] | 5.3 |
| Shelter for grazing animals | 80 m² and 3 m high, on meadow only, no storage [2] | 5.1, 3° |
Enclosed agricultural buildings (sheds, shelters) remain subject to a permit [2]. For buildings other than homes, article 3.1 does not exempt new volume: it covers work on facades, roofs, insulation or solar panels [2]. A commune can bring some exempt acts back under permit through an urban planning regulation (article 4.2.5 VCRO): to be verified.
A legal publication dated 28 September 2026 points to a return of the mandatory architect for stability works exempt from a permit in Flanders since 1 March 2026. We did not read that page: to be verified [15].
Brussels (CoBAT)
The Government decree of 13 November 2008 on exemptions (title II, unprotected properties) exempts an isolated accessory building not used for housing, commerce or industry if it stands in the courtyards and gardens zone, covers at most 9 m² (roof projection included) and is at most 3.00 m high within a defined envelope. Above that, a permit is required [5].
The text we read is an undated version. The decree has been amended (2011 at least) and a draft amendment is mentioned: to be verified [5]. Kit halls are rare in the region: 50 new non-residential buildings were permitted there in 2025 [6].
Netherlands (Omgevingswet, Bbl, Wkb)
- The Omgevingswet and the Wkb have applied since 1 January 2024 [7].
- The Bbl list of permit-free work (article 2.29) covers maintenance, dormers, solar panels, garden furniture and fences up to 1 m. It contains no hall or shed [8].
- A home outbuilding (bijbehorend bouwwerk) falls under the bruidsschat of the omgevingsplan, articles 22.27 and 22.36: rear garden, functionally subordinate to the house, limited height and pitch, total area capped at 150 m² [8]. A company hall is not one [8].
- Agricultural: only a structure that is not a building (a silo or other work up to 2 m) is exempt in the rear garden. For a shed or stable, two tracks are checked separately. The planning track (omgevingsplanactiviteit) depends on the municipality's omgevingsplan, including the bruidsschat rules [8]. The technical track (technische bouwactiviteit) needs, depending on how the project is classified, a permit or a notification with a kwaliteitsborger under the Wkb [7]. How a shed or stable is classified is to be verified.
- The bruidsschat rules apply until the municipality sets its own, by the end of 2031 at the latest [8]. The local plan can therefore impose its own limits: to be verified municipality by municipality.
Wkb: since 1 January 2024, a kwaliteitsborger (quality assurer) checks new buildings in gevolgklasse 1 (single-family homes, smaller business premises). A kwaliteitsborger is required when the project falls under the Wkb notification regime: have the classification of your building confirmed. A completion notice (gereedmelding) is required before use for works subject to notification (article 2.21 Bbl) [7]. The exact classification of storage sheds and stables in gevolgklasse 1 is not confirmed: to be verified [7].
Luxembourg (autorisation de bâtir, PAG, PAP, green zone)
The autorisation de bâtir is issued by the mayor. It is required for any construction, alteration, change of use or demolition, and for most earthworks. The works must comply with the PAG, the applicable PAP and the building regulation. The authorisation lapses if major works do not start within 2 years (one-year extension possible). An appeal can be lodged within 3 months after the certificate is posted on site, exact starting point to be confirmed [9].
In the green zone, a structure with a certain and lasting link to an agricultural, horticultural, wine-growing, forestry or similar activity complies with the land use, but still needs the authorisation of the Minister of the Environment (articles 6 and 7 of the law of 18 July 2018). The Minister decides within 3 months of the complete file, can impose conditions (dimensions, finish, landscape integration, compensation), and silence counts as refusal [10].
To be verified as a priority. A draft grand-ducal regulation on certain structures in the green zone, published in December 2021 (adoption status to be verified), provides for sheds and stables vertical cladding in durable timber at least 24 mm thick, unplaned and untreated, timber doors with a metal frame, pitched roofs in non-reflective slate grey, a concrete slab and a footprint of at most 60 x 35 m for the main part. If adopted as it stands, a sheet-steel kit would not comply in the green zone without timber cladding [11]. A more recent bill (8578) aims to amend the 2018 law: to be verified.
The role of the ingénieur-conseil and Luxembourg fire regulations are not covered here: to be verified with the commune.
Architect in Belgium, the commune and the Hallfort file
The law of 20 February 1939 requires an architect for the plans and the supervision of works that need a prior building authorisation (article 4). The Regions have since set their own lists of exempt works [12]. Article 6 makes the profession of architect incompatible with that of public or private works contractor [12]. The company that sells and erects the kit therefore cannot be the architect: the client appoints an independent architect for any hall that needs a permit. The exemptions we read cover small outbuildings, not halls. Possible agricultural or industrial exceptions are to be verified with the Order of Architects [12].
No Belgian fee scale could be confirmed. As a German order of magnitude only: 30,000 euros for an architect on a 450 m² hall, in September 2025 [14].
What Hallfort provides for the file: the plans, the fabricator's structural calculation notes and coordination with the architect of your choice. The permit and the architect are not included in the price unless the quote says so. Hallfort never promises that a permit will be granted. The final calculation note follows the stability study for your site (snow, wind): see snow and wind loads.
Before filing, also check fire safety. In Belgium, annex 6 of the royal decree of 7 July 1994 covers new industrial buildings, excluding single-storey buildings of 100 m² or less. The case of non-industrial agricultural buildings is not confirmed: to be verified [13]. Next, see foundations for steel buildings, the carports and shelters range and the quote request.
Frequently asked questions
Does a steel carport need a permit in Wallonia?
Not if it meets every condition: the only one on the property, directly linked to the access road, 40 m² at most, 2.50 m to the eaves, 3.50 m to the ridge, timber, concrete or metal posts [1]. Otherwise it falls under the limited-impact permit without an architect [1]. Thresholds to be verified against the current CoDT.
Can I build a steel garage or outbuilding without a permit in Flanders?
Yes, under conditions: 40 m² in total per property, 3.5 m high, 3 m from the boundary in the side zone or 1 m in the rear garden, within 30 m of the house [2]. A commune can restrict these exemptions: to be verified.
Is a steel agricultural shed exempt from a permit?
Not according to the texts we read. In Wallonia, no conventional agricultural shed is in the list [1]. In Flanders, enclosed agricultural buildings remain subject to a permit [2]. In the Netherlands, sheds and stables are not in the permit-free list [8]: the omgevingsplan and the project's classification (permit or notification) decide, to be verified [7]. In Luxembourg, the green zone adds the Minister's authorisation [10].
Is an architect mandatory for a hall in Belgium?
In principle yes for a hall that needs a permit, unless a regional exemption applies. The exemptions we read do not cover halls [12]. The architect must be independent of the company that sells and erects the kit (article 6 of the 1939 law) [12].
Does Hallfort obtain the permit for me?
No. Hallfort helps with the file (plans, the fabricator's calculation notes, coordination with your architect) but never promises a permit. The commune or the competent authority decides.
Sources
- Walloon Region, CoDT, table R.IV.1-1 (small permits, updated to 2021), accessed on 2026-10-24
- Codex Vlaanderen, vrijstellingenbesluit of 16 July 2010 (consolidated version), accessed on 2026-10-24
- Codex Vlaanderen, decree of 23 May 2003 on the exemption from an architect, accessed on 2026-10-24
- Omgeving Vlaanderen, vrijstelling medewerking architect, accessed on 2026-10-24
- Urbanisme Bruxelles, decree of 13 November 2008 on exemptions, title II, accessed on 2026-10-24
- Statbel, building permits, accessed on 2026-10-24
- IPLO, Wet kwaliteitsborging voor het bouwen (Wkb), accessed on 2026-10-24
- IPLO, omgevingsplanactiviteit bouwwerken, transposition tables, accessed on 2026-10-24
- Guichet.lu, autorisation de bâtir, accessed on 2026-10-24
- Administration de la nature et des forêts, nature protection (green zone), accessed on 2026-10-24
- Ministry of the Environment, draft grand-ducal regulation on the green zone (December 2021), accessed on 2026-10-24
- Law of 20 February 1939 on the protection of the title and profession of architect (Justel), accessed on 2026-10-24
- Buildwise, royal decree of 7 July 1994, basic standards (annex 6), accessed on 2026-10-24
- Haltec, cost of building a hall (German example, September 2025), accessed on 2026-10-24
- Lexgo, architect involvement in stability works exempt from a permit (28 September 2026), accessed on 2026-10-24