FAQ

XVB vs. VOB Cable: Which Is Right for Your Installation?

Comparison between XVB sheathed cable and VOB single-core wire for Belgian electrical installations according to AREI/RGIE standards.

Published on 16 March 2026 4 min min read

XVB vs. VOB Cable: Which Is Right?

XVB is the standard sheathed cable for fixed wiring in Belgian new installations. It contains multiple conductors with an outer sheath and can be installed directly in walls, floors, or conduits. VOB, on the other hand, is a single-core wire that must always be placed inside a protective conduit or cable trunking.

What Is XVB?

XVB (e.g., XVB 3G2.5) is a multi-core sheathed cable with PVC insulation and PVC outer sheath. The designation indicates the number of cores and cross-section. XVB is designed for fixed installation — in wall chases, under plaster, in conduits, or on cable trays.

What Is VOB?

VOB (e.g., VOB 2.5mm²) is a flexible single-core wire with PVC insulation. It must never be installed freely and always requires a protective conduit (tube) or cable trunking. VOB is cheaper per meter but requires the additional cost of protective tubing.

Comparison Table

PropertyXVBVOB
ConstructionMulti-core with outer sheathSingle core without sheath
InstallationDirectly in wall, floor, conduitOnly in conduit/trunking
Conduit required?No (optional)Yes, always
Price per meterHigher (~€1.50–3.00/m for 3G2.5)Lower (~€0.30–0.50/m per core)
Total costOften cheaper (no conduit needed)Conduit + labour = more expensive
FlexibilityStiffer, harder to bendMore flexible inside conduit
Typical useNew construction, renovationRenovation in existing conduits

AREI/RGIE Requirements

AREI ArticleRequirement
Art. 5.2.2Cables must be suitable for the installation method; single-core wires (VOB) only in electrical conduits or cable trunking
Art. 5.2.7.2 / 5.2.7.3CPR fire class: individually installed cables require at least Eca (Art. 5.2.7.2). In bundles, hollow walls, and building cavities, at least Cca is required (Art. 5.2.7.3, Art. 4.3.3.5b)

Recommendation

For new installations, XVB is the first choice: fewer work steps, no protective conduits needed, and AREI-compliant. VOB is mainly suitable for renovations where conduits already exist and individual wires need to be pulled through.

For both cable types, ensure compliance with the required CPR fire class — in hollow walls and escape routes Cca-s1,d2,a1, in solid walls under plaster Eca is sufficient. Older cables without CPR classification may no longer be used in new installations.

Colour coding (Art. 5.1.6.2): Conductor colours must comply with the AREI: Green-Yellow = protective conductor (PE), Blue = neutral (N), Brown/Black/Grey = phase conductors (L1/L2/L3).

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