Old Buildings and AREI Part 8: Special Rules for Existing Installations
What applies to older electrical installations in Belgium. AREI Part 8 explained: permitted deviations, periodic inspection, and tips for gradual modernisation.
Not every electrical installation in Belgium needs to comply with the latest AREI/RGIE regulations. For older buildings, Part 8 (Partie 8) provides a dedicated set of rules that tolerates certain deviations from the current standard — as long as no immediate danger exists. This article explains when Part 8 applies, what is permitted, and where the limits lie.
What Is Part 8?
Part 8 of the AREI (Algemeen Reglement op de Elektrische Installaties / Règlement Général sur les Installations Électriques) is a special regulation for existing installations that were constructed and approved before the current AREI came into force.
The basic principle: as long as an installation functions safely and poses no immediate danger, it does not need to be fully brought up to the latest standards — even if it does not meet all current requirements.
Important: Part 8 is not a free pass. It clearly defines which deviations are tolerated and which are not.
When Does Part 8 Apply?
Part 8 applies to installations that meet one of the following conditions:
Condition 1: Installation Before 01.10.1981
Installations constructed before 1 October 1981 (the date the original AREI came into force) fall under Part 8 by default.
Condition 2: Approved Under the Old AREI
Installations that were approved under a previous version of the AREI and have not been substantially modified since the last approval.
What Counts as a "Substantial Modification"?
- Adding new circuits
- Expanding the distribution board
- Modifying the metering installation
- Extensive rewiring
Note: Small changes such as replacing a socket outlet or switch do NOT count as a substantial modification.
What Is Permitted Under Part 8? (Tolerated Deviations)
The following points deviate from the current AREI but are tolerated under Part 8 during inspection:
1. Old Cable Types
| Current AREI | Part 8 tolerates |
|---|---|
| XVB / VOBst in Preflex | VOB cables in old conduits |
| Cca fire reaction class | Older cable types without CPR classification |
| Minimum cross-section 2.5 mm² for sockets | Minimum 1 mm² with max. 6A fuse or 10A MCB (Art. 8.2.1 Nr. 5) |
2. Residual Current Devices (RCD)
| Current AREI | Part 8 tolerates |
|---|---|
| 30 mA RCD per socket circuit | No 30 mA RCD needed (only 300 mA main RCD) |
| 30 mA RCD mandatory for bathroom | Remains mandatory (not covered by the Part 8 deviation, Art. 4.2.4.3 b No. 3 / Art. 7.1.4.3) |
| Max. 8 circuits per RCD | More circuits permitted |
Note: Even under Part 8, a 300 mA main RCD is recommended and often required by the grid operator when a new meter is installed.
3. Socket Outlets Without Earth Contact
Old socket outlets (type C, without earth pin) are tolerated under Part 8, provided that:
- The socket is protected by a high or very high sensitivity RCD (max. 30 mA) (Art. 8.2.1 No. 6 letter b).
- No Class I appliances (with metal housing) are connected.
- The socket is not in the bathroom or in a damp location.
- The circuit is otherwise intact.
4. No SPD (Surge Protection)
The current AREI requires a Type 2 SPD (Surge Protection Device) for new installations. Under Part 8, this is not required.
5. Old Distribution Technology
- Fuses instead of MCBs are permitted.
- Screw-type fuses (Diazed) are tolerated.
- Missing labelling is noted as a deficiency but does not cause a failure.
6. No Fire Reaction Classification of Cables
Cables without CPR classification (installed before 2017) are tolerated, as the CPR regulation only applies from July 2017 for new installations.
What Is NOT Permitted (Even Under Part 8)?
Certain conditions are never tolerated, regardless of the installation's age:
Absolutely Impermissible:
| Condition | Why? |
|---|---|
| Bare or damaged cables | Immediate electrocution risk |
| Complete absence of earthing | No protection in case of insulation fault |
| Water in contact with electrics | Danger to life |
| Accessible live parts | Direct contact risk |
| Overheated cables or connections | Fire risk |
| Loose connections in junction boxes | Arc/fire risk |
| Junction boxes without covers | Contact protection missing |
| Bathroom socket in zone 0 or 1 | Danger to life, prohibited even under Part 8 |
Safety-Related Minimum Requirements:
Even under Part 8, the following must be ensured:
- Adequate cross-section for the actual load (no overloaded 0.75 mm² cable).
- Functioning fuses (no "bridged" fuses).
- Earthing of the main board (connection to earth electrode).
- Accessibility of the distribution board.
Periodic Inspection
Periodicity depends on the installation history
A blanket “every old installation every 25 years” statement is not accurate. The FPS Economy distinguishes installations already controlled under the AREI from old pre-1 October 1981 installations that were never brought into that control history. Sale, significant modification or extension, power increase and earlier report conditions can trigger different visits and deadlines. Check the official case guidance and the latest report.
On Change of Ownership
When selling a property, a valid inspection certificate (less than 25 years old) is mandatory. If none exists, an inspection must be carried out before the sale.
18-month deadline (Art. 8.4.2.2): When purchasing a property with a negative inspection report, the buyer has 18 months from the purchase date to remedy the defects and have a re-inspection carried out.
What Is Checked During the Periodic Inspection?
| Inspection Point | Assessment |
|---|---|
| Visual inspection of cables and connections | Damage, overheating |
| Earth resistance measurement | ≤ 30 Ohm (regulatory threshold per Art. 4.2.4.3b; above this, additional protective measures required) |
| Insulation resistance measurement | > 0.5 MOhm |
| RCD test (if present) | Trip time and current |
| Short-circuit protection check | Fuses / MCBs present |
| Protection against direct contact | Covers, IP protection |
| Documentation | Single-line diagram + situation plan present? |
Note: Even under Part 8, a single-line diagram and a situation plan must be available — even if they need to be created retrospectively.
The Contamination Rule for Partial Renovations
A particularly important aspect for old buildings: the so-called contamination rule.
How Does It Work?
When you substantially modify part of your installation (e.g., adding new circuits):
- The new part must fully comply with the current AREI.
- The existing part continues to be assessed under Part 8.
- BUT: If the new part "contaminates" the existing part (e.g., new cables in the same distribution board), the inspector may decide that the entire board must comply with the current AREI.
Practical Consequences:
- Plan renovations so that new and old parts are clearly separated.
- Ideally, use a separate sub-board for new circuits.
- Document precisely what is old and what is new.
Recommendation: Gradual Modernisation
Even though Part 8 tolerates deviations, gradual modernisation is recommended:
Priority 1 (Safety-Critical)
- Retrofit a 300 mA main RCD (if not present)
- Replace damaged cables
- Fix loose connections
- Check and improve earthing if necessary
Priority 2 (Recommended)
- 30 mA group RCDs for bathroom and kitchen
- Replace old fuses with MCBs
- Retrofit SPD Type 2
Priority 3 (Comfort + Future-Proofing)
- Modernise the board (more rows, labelling)
- Retrofit socket outlets with earth
- Preparation for EV charger / PV system
Scope work before pricing
Do not use a generic online price range as a factual budget. Have the existing installation inventoried, classify safety defects separately from optional improvements, and request a dated quotation for the actual building. Cable routes, finishes, accessibility, board condition and the intended renovation scope change the work materially.
Summary
| Question | Answer |
|---|---|
| Does my old building need to comply with the current AREI? | Not fully, Part 8 permits deviations |
| Do I need a 30 mA RCD? | Not mandatory under Part 8, but strongly recommended |
| Are old sockets without earth permitted? | Under conditions yes (no bathroom, no Class I appliances) |
| How often must inspections take place? | Depends on control history and trigger; sale rules are case-specific |
| What about partial renovation? | New part = current AREI, old part = Part 8 (scope must be established from the regulation) |
Related Articles
- Electrical Inspection in Belgium: What Is Checked?
- What Changes with the AREI 2026?
- Preflex vs. Open Wiring
- Distribution Board Planning
For older buildings, PlanElec helps build the single-line diagram and situation plan digitally. The self-check is advisory; have the documents and applicable derogations reviewed professionally. Start for free →
Determine the legal history before choosing a derogation
The date of the building is not enough. Build a timeline from earlier inspection reports, board labels, invoices, permits and visible construction. Identify which parts existed before 1 October 1981, which were later modified or extended, and whether those later works received a conformity inspection. Part 8 defines old installations and specific derogations; it does not turn every component in an old house into an exempt component.
Mark old and new parts on a working copy of the single-line diagram. For every proposed derogation, record the exact V06 provision, the circuit concerned, the evidence of age and the remaining safety conditions. If evidence is missing, label it unknown rather than assigning a date from cable colour or appearance. The approved control body determines whether the derogation applies to the actual installation.
Do not use the informal “contamination rule” as if it were an AREI article. A significant modification or extension is assessed under the applicable current provisions, while the status of existing parts depends on definitions, scope and inspection history. Shared boards and protective measures can make the boundary important, but the correct scope must be established from regulation and project, not a slogan. Ask the control body before work when the boundary affects the renovation strategy.
For a sale, follow the FPS Economy sale FAQ. It distinguishes seller duties, buyer communication and the 18-month route after a negative sale inspection. That route is not interchangeable with the 12-month follow-up for other negative controls. The authentic deed date and report type matter.
The handover file should contain current diagrams, reports, declarations, instructions and subsequent modifications. PlanElec can help reconcile identifiers, but does not decide derogation eligibility or cover every Part 8 case. Reviewed on 29 August 2026 against Book 1 V06 and the FPS page updated 1 April 2026.