What is Cablofil cable basket?

Cablofil is the leading brand name for wire mesh cable basket, manufactured by Legrand. Cablofil cable basket is constructed from galvanised steel wire welded into a mesh pattern, formed into a channel shape. The brand name Cablofil is used generically by many UK electricians to refer to any wire mesh cable basket, in the same way as other brand names become generic terms. Other manufacturers produce similar products, including OBO Bettermann and Niedax. BS 7671 does not define "cable basket" as a term — for current-rating purposes it is treated as a perforated cable tray or a cable ladder, both of which take Reference Method E or F.

What reference method applies to cables on wire cable basket?

Reference Method E or F — the free-air methods. Appendix 4 of BS 7671 states that a perforated cable tray has a regular pattern of holes occupying at least 30% of the area of the base, and that the current-carrying capacity for cables attached to perforated cable trays should be taken as Reference Method E or F. It also states that for a cable ladder system, where supporting metalwork under the cables occupies less than 10% of the plan area, the current-carrying capacity should be taken as Reference Method E or F. Wire mesh basket sits comfortably inside both descriptions. By contrast, an unperforated tray, or one whose holes occupy less than 30% of the base, is rated as Reference Method C.

Can cable basket be used for power cables?

Yes. Wire cable basket is suitable for both power cables and data/communications cables, and is used extensively for power distribution in commercial buildings and data centres. For power circuits, the basket must be earthed as a system, and cable sizing must apply the BS 7671 Appendix 4 correction factors — Ca for ambient temperature (Table 4B1), Cg for grouping (Tables 4C4 and 4C5 for free air) and Ci for thermal insulation where cables leave the basket. Manufacturers typically recommend keeping cross-sectional fill to around 40% to preserve ventilation, but that figure is manufacturer guidance, not a BS 7671 threshold — the regulatory mechanism for maintaining current ratings is the Cg grouping calculation in Appendix 4.

How do you earth wire cable basket?

Bond section-to-section with earth bond connectors at every joint, and connect the system to the installation's main earthing terminal. Cablofil and other manufacturers supply clip-on earth bond connectors that attach to the wire mesh without drilling. The protective conductor cross-section is either selected from BS 7671 Table 54.7 (Regulation 543.1.4) or calculated using the adiabatic equation in Regulation 543.1.3 from the earth fault current and the disconnection time of the upstream device. Where that conductor is a separate conductor rather than part of a cable or an enclosure, Regulation 543.1.1 sets a floor of 2.5mm² copper equivalent if it is mechanically protected and 4mm² if it is not. Regulation 543.3.2 requires every connection and joint to be accessible for inspection, testing and maintenance.

What support spacing is required for cable basket?

BS 7671 does not tabulate support spacing for cable containment — it requires only that wiring systems be supported so they are not liable to premature collapse in the event of fire (Regulation 521.10.202). Spacing comes from the manufacturer's load/span tables. As a general guide, standard Cablofil CF54 series basket requires supports at 1500mm centres maximum for horizontal runs with typical cable loading. Wider baskets and heavy cable loads need closer spacing, and additional supports are required within 300mm of bends, tees and changes of direction. Always confirm against the load/span table for the series and the actual cable load.

How far apart should power and data cables be on basket?

Where the specification and intended application of the data cabling are known, BS 7671 points to BS EN 50174-2 and BS EN 50174-3. Where they are not known, informative Annex A444 of BS 7671 recommends a minimum separation of 200mm in free air, and Table A444.1 allows that to be reduced by the containment used on the power cabling: 200mm where there is no containment or open metallic containment (the screening performance of a welded mesh steel basket of 50mm x 100mm mesh, ladders excluded), 150mm for perforated open metallic containment, and no separation beyond that provided by the containment itself for solid metallic containment. Separately, Regulation 444.6.2 sets a minimum 130mm between information and communications technology cables and discharge, neon and high-intensity discharge lamps.

Can cable basket be used outdoors?

Standard hot-dip galvanised (HDG) wire basket is suitable for sheltered outdoor use where it is not in direct contact with weather. For fully exposed outdoor installations, stainless steel (316 grade) wire basket is required. PVC-coated wire basket is also available and provides good corrosion resistance for external or humid environments. Standard pre-galvanised (electro-galvanised) basket is for indoor dry use only — the thin zinc coating will corrode rapidly in outdoor or humid conditions.

How do you bend cable basket?

Cablofil cable basket can be shaped using a dedicated basket bending tool (supplied by Cablofil/Legrand) that folds the basket without cutting. For gentle bends, the basket can be bent by hand or over a suitable former — the wire mesh construction allows controlled deformation without cracking. For right-angle bends and tees, purpose-made corner pieces and tee connectors can be ordered, or the basket can be cut and re-formed on site using the bending tool. This on-site flexibility is one of the major advantages over pressed steel tray, which requires factory-made fittings for all changes of direction.

Is cable basket suitable for fire-resistant cable installations?

Wire cable basket can be used to support and route fire-resistant cables such as FP200 Gold and MICC cable, subject to the fire strategy for the building. Regulation 521.10.202 requires wiring systems to be supported so they are not liable to premature collapse in the event of fire, and its NOTE 2 states that cables installed in or on steel cable containment systems are deemed to meet that requirement. Note carefully what that regulation is for: NOTE 5 states its intent is to prevent the general collapse of wiring systems that would hinder evacuation, rescue or firefighter access — it is expressly not intended to provide support that maintains circuit integrity for life safety or firefighting applications. Those requirements sit in Chapter 56 and in BS 5266, BS 5839 and BS 8519, so follow the fire engineer's design and the cable manufacturer's fixing requirements for circuit integrity.

INSTALLATION GUIDE

Wire Cable Basket Installation UK: Wiremesh Tray Guide

Everything electricians need on wire cable basket (Cablofil type) — sizes and finishes, the reference method and grouping factors that drive cable sizing, support spacing, earthing, power/data separation and cost against solid tray.

Start 7-day free trial

Free for 7 days · No charge until day 8 · Cancel anytime · Used by 1,000+ UK electricians

12 min readUpdated 2026-08-07Andrew Moore, Founder of Elec-Mate

Written and reviewed by Andrew Moore, founder of Elec-Mate, against BS 7671:2018+A4:2026, IET Guidance Note 3 and the IET On-Site Guide.

ShareX in W

The short answer

What is wire cable basket and what is it used for?

Wire cable basket is a cable management system made from welded steel wire mesh formed into a channel. It is a lighter, faster-to-install alternative to pressed steel cable tray, used to route power and data cables in commercial buildings and data centres. Its open mesh gives excellent airflow, easy cable identification and on-site flexibility. Like all metallic cable management, it must be earthed.

Cables on basket are rated as being in free air. BS 7671 Appendix 4 takes the current-carrying capacity for cables on a perforated tray — holes covering at least 30% of the base — or on a cable ladder as Reference Method E or F.

1,000+

UK electricians

“Replaced three separate apps with Elec-Mate. Certs, quotes, and scheduling all in one place.”
Daniel Palmer, DP Electrical · 5 out of 5

Key takeaways

01Wire cable basket — commonly known by the brand name Cablofil (manufactured by Legrand) — is a cable management system made from welded steel wire mesh, offering a lightweight, flexible alternative to pressed steel cable tray.
02Because the mesh is open, cables on basket are rated as being in free air. BS 7671 Appendix 4 takes the current-carrying capacity for cables on a perforated tray (holes covering at least 30% of the base) or on a cable ladder as Reference Method E or F.
03Grouping is the factor that usually forces an upsize on a loaded basket. The free-air grouping factors are in Appendix 4 Table 4C4 (multicore, Reference Method E) and Table 4C5 (single-core, Reference Method F) — not the bunched factors in Table 4C1.
04Wire mesh basket can be cut and modified on site with side cutters or bolt croppers and shaped with a bending tool, which cuts installation time on complex routes.
05Basket is a metallic cable management system. Regulation 543.2.1(f) recognises it as something that may serve as a protective conductor, so joints must be bonded, continuity must be verified, and the earthing conductor sized from Table 54.7 (Regulation 543.1.4) or by the adiabatic equation in Regulation 543.1.3.
06Where the specification of the data cabling is not known, BS 7671 informative Annex A444 recommends a minimum 200mm separation between power cabling on open metallic containment (welded mesh basket) and information technology cabling.

01 · Installation Guide

What is Wire Cable Basket?

Wire cable basket (commonly referred to as Cablofil, after the leading brand) is a cable management system constructed from galvanised steel wire welded into a rectangular mesh pattern and formed into a channel shape. It is an alternative to pressed steel cable tray, offering a lighter, more flexible, and faster-to-install solution for routing multiple cables in commercial and data centre environments.

How BS 7671 classifies it

BS 7671 has no definition of “cable basket”. For current-rating purposes it falls under the descriptions Appendix 4 gives for perforated cable tray and cable ladder, and both take the free-air reference methods:

Support	Appendix 4 description	Reference method
Perforated tray	Holes occupy at least 30% of the area of the base	E or F
Cable ladder	Supporting metalwork under the cables occupies less than 10% of the plan area	E or F
Unperforated tray	No holes, or holes under 30% of the base area	C

Wire mesh basket sits comfortably inside the first two, so cables on basket are rated as being in free air — the same basis as a perforated cable tray. That single fact drives the whole sizing exercise, because it determines both the base current-carrying capacity column you read and the grouping table you correct it with.

Why installers choose it

Fast installation: Cables are laid into the open mesh rather than threaded, and route changes are made on site without waiting for factory fittings.
Open and accessible: Cables can be seen, identified and accessed without removing a lid, so later additions are straightforward.
Lightweight: Wire basket weighs considerably less than equivalent solid steel tray, reducing structural loading and making handling easier.

Cable basket must be installed in compliance with BS 7671:2018+A4:2026 requirements for cable support, grouping, segregation and earthing.

Free download

Get the BS 7671 A4:2026 Cheat Sheet — free

Every key change in the 2026 amendment on one page. AFDDs, TN-C-S protection, new schedule columns, model forms. Pinned on your van dash.

Every regulation change summarised
New model forms (EIC + MEIWC)
Free PDF — no subscription

02 · Installation Guide

Sizes, Types and Finishes

Cablofil and equivalent wire basket systems come in a range of widths, depths and wire diameters. The table below summarises the specification ranges you will meet on UK commercial projects — these are manufacturer product ranges, not BS 7671 figures, so confirm against the catalogue for the series you are pricing.

Dimension	Typical range	Most common
Width	50mm – 600mm	100 / 150 / 200 / 300 / 450mm
Depth	35mm – 105mm	54mm (standard commercial)
Wire diameter	~2.9mm – 5mm	2.9mm (Cablofil CF54 series)

Choosing a width

Size the width from a cable fill calculation, then check the result against the grouping derating covered in the cable sizing section below. Manufacturers typically recommend a maximum cross-sectional fill of around 40% to preserve ventilation and keep cables in something close to free-air conditions. That 40% figure is manufacturer guidance and appears nowhere in BS 7671 — the standard controls heating through the C_g grouping factor instead, and it is that calculation, not the fill percentage, that decides whether conductors need upsizing. Deeper basket (the 105mm deep-section profile, for example) and heavier wire allow higher cable volumes and wider support spans.

Finishes by environment

Finish	Where it is suitable
Pre-galvanised (electro-galvanised)	Indoor, dry use only. The thin zinc coating corrodes rapidly in damp or external conditions.
Hot-dip galvanised (HDG)	Indoor, and sheltered outdoor use where not in direct contact with weather.
PVC coated	Humid or mildly corrosive environments, including wash-down areas.
Stainless steel 316	Fully exposed outdoor, marine and corrosive environments where galvanising will not last.

03 · Installation Guide

Cable Sizing on Basket: BS 7671 Appendix 4

Start from the tabulated current-carrying capacity (I_t) for your cable type in the Reference Method E or F column of the relevant Appendix 4 table, then apply the correction factors that actually bear on a basket installation.

Factor	What it corrects for	BS 7671 source
C_a	Ambient temperature above 30°C (ceiling voids, plant rooms)	Appendix 4, Table 4B1
C_g	Grouping — mutual heating from other circuits on the basket	Table 4C4 (multicore, Method E) / Table 4C5 (single-core, Method F)
C_i	Contact with thermal insulation where cables leave the basket	Reg 523.9; Appendix 4 Section 2.6

C_a — ambient temperature: Where the ambient temperature in the ceiling void or plant room exceeds 30°C, apply the factor from Table 4B1. For 70°C thermoplastic (PVC) cables at 40°C ambient, C_a = 0.87. Table 4B1 stops at 60°C for that insulation — above that the entry is a dash and a different cable type is needed.
C_g — grouping (the one that bites): Because basket is rated as free air, the grouping factor comes from Appendix 4 Table 4C4 for multicore cables (Reference Method E) or Table 4C5 for circuits of single-core cables (Reference Method F) — not the bunched and enclosed factors in Table 4C1, which are more severe and do not apply here. The free-air tables are read against the number of cables, the number of tiers of tray or ladder, and whether the cables are touching or spaced; the factor falls as any of those increases. Look up the value for your actual arrangement rather than carrying a remembered figure — on a loaded basket this derating, not the fill percentage, is what forces an upsize.
C_i — thermal insulation: Does not normally apply on open basket, but does apply if cables leave the basket and pass through or touch thermal insulation. Regulation 523.9 requires a cable totally surrounded by insulation over 0.5m or more to be taken at 0.5 times its Reference Method C rating; for lengths under 0.5m the factors in Appendix 4 Section 2.6 apply, for conductor sizes up to 10mm².

Putting it together

The derated capacity is I_z = I_t × C_a × C_g (× C_i where it applies). Regulation 433.1.1 then requires the protective device to satisfy I_b ≤ I_n ≤ I_z — the rated current of the device must be at least the design current of the circuit and must not exceed the lowest current-carrying capacity of any conductor in it. Regulation 433.1.1(c) adds that the current causing effective operation of the device must not exceed 1.45 × I_z.

04 · Installation Guide

Support Requirements for Wire Cable Basket

Wire cable basket must be supported well enough to prevent deflection under cable loading; because the mesh is flexible it will sag more than rigid pressed steel tray if supports are too far apart. BS 7671 does not tabulate spacing for containment — the figures below are typical manufacturer guidance, and you should confirm them against the load/span table for the series and the cable load you are actually installing.

Location	Typical max support spacing
Horizontal straight run (CF54, standard load)	1500mm centres
Heavily loaded or wide basket	1200mm or 1000mm centres
Either side of a bend, tee or direction change	Within 300mm of the fitting
Vertical run	1200mm centres, plus cleats or ties for cable weight

Regulation 521.10.202 — support in fire

Regulation 521.10.202 requires wiring systems to be supported such that they will not be liable to premature collapse in the event of a fire. It applies throughout the installation, not only on escape routes.

Steel basket is deemed to comply: NOTE 2 to the regulation states that cables installed in or on steel cable containment systems are deemed to meet its requirements — which is a strong argument for steel basket over non-metallic containment on any route where fire performance is scrutinised.
Plastic clips and ties cannot be the sole support: NOTE 3 states that the regulation precludes the use of non-metallic cable clips or cable ties as the sole means of support, including where cables are suspended under cable tray. Use steel or copper clips, saddles or ties (NOTE 4), and keep the hangers and fixings metallic too.
It is not a circuit-integrity requirement: NOTE 5 is explicit that the intent is to prevent general collapse of wiring systems that would hinder evacuation, rescue or firefighter access — not to maintain circuit integrity for life safety or firefighting. Those requirements sit in Chapter 56 and in BS 5266, BS 5839 and BS 8519.
Support the joints, not just the spans: Joints are the weakest point in a basket run, so position supports close to every connector and fitting rather than at mid-span only. Threaded rod hangers with the manufacturer's brackets are the usual method for suspended runs; wall brackets and ceiling clips for surface work. Fix into structural elements, not lightweight partitions.

05 · Installation Guide

Earthing Wire Cable Basket

Wire cable basket is a metallic cable management system — part of the wiring system, so not an extraneous-conductive-part, which BS 7671 Part 2 defines as a conductive part liable to introduce a potential and not forming part of the electrical installation. Regulation 543.2.1(f) recognises a metal conduit, metallic cable management system or other electrically continuous support system for conductors as something that may serve as a protective conductor, which is why continuity across the whole run matters and why it is bonded back to the main earthing terminal.

Bond at every joint: Fit an earth bond at every connection between basket sections. The mechanical joint alone cannot be relied on for continuity — mesh-to-mesh contact through a galvanised finish can be a high resistance. Cablofil and other manufacturers supply clip-on earth bond connectors that attach to the wire mesh without drilling, which is appreciably quicker than the bolted bonds used on pressed steel tray.
Size the conductor from Table 54.7 or the adiabatic: Regulation 543.1.1 gives two routes: calculate to Regulation 543.1.3 (the adiabatic equation, valid for disconnection times up to 5s), or select from Table 54.7 under Regulation 543.1.4. Where Table 54.7 produces a non-standard size, the next larger standard size is used. Where the protective conductor is a separate conductor rather than part of a cable, formed by conduit/ducting/trunking, or contained in an enclosure formed by a wiring system, Regulation 543.1.1 sets a floor of 2.5mm² copper equivalent if mechanically protected and 4mm² if not.
Keep connections accessible: Regulation 543.3.2 requires every connection and joint in a protective conductor to be accessible for inspection, testing and maintenance, except as allowed by Regulation 526.3. Plan bond positions so they are not buried behind later trades' work. Make the system earth connection at the origin of the basket run, nearest the distribution board or panel.
Test and record the continuity: Regulation 643.2.1(a) requires the continuity of conductors and of connections to exposed-conductive-parts and extraneous-conductive-parts to be verified by a measurement of resistance of the protective conductors, including protective bonding conductors. In practice, test with a low-resistance ohmmeter between the origin earth connection and remote sections of basket; a well-bonded system reads a fraction of an ohm. Record the readings on the schedule of test results.

In the app

Try Elec-Mate free for 7 days

16 certificate types, 70+ calculators, RAMS, quoting, invoicing, AI agents, and 46+ training courses — from £6.99/mo.

Start free trial

06 · Installation Guide

Power and Data Separation on Basket

Run power and data on separate basket wherever the design allows. Regulation 444.6.1 states that Band II (low voltage) and Band I (extra-low voltage) cables sharing the same cable management system or the same route shall be installed according to Regulations 528.1 and 528.2, and adds that circuits of the same voltage band might also need segregating: electrical safety and electromagnetic compatibility can produce different requirements, and the design must meet both.

Regulation 528.1 sets out the permitted methods, one of which — item (d) — is cables installed on a cable tray system where physical separation is provided by a partition. So a divider down a shared basket is an explicitly recognised arrangement. (Regulation 528.2 is often mis-cited here: it deals with crossings and proximity of underground telecommunication and power cables, where a minimum 100mm clearance or a fire-retardant partition is required. Its NOTE 2 is the useful part above ground — it points to BS 6701 and the BS EN 50174 series for communications segregation.)

How much separation — Annex A444

Where the specification and intended application of the data cable are known, BS 7671 directs you to BS EN 50174-2 and BS EN 50174-3. Where they are not, informative Annex A444 recommends a minimum of 200mm in free air, reducible according to the containment used on the power cabling:

Containment on the power cabling	Minimum separation
No containment, or open metallic containment (A)Screening equivalent to welded mesh steel basket of 50mm x 100mm mesh (ladders excluded), or steel tray under 1.0mm wall with more than 20% perforation	200mm
Perforated open metallic containment (B)Steel tray of 1.0mm wall thickness with no more than 20% perforation	150mm
Solid metallic containment (C)Fully enclosed steel containment, minimum 1.5mm wall thickness	No physical separation beyond that provided by the containment

Two practical points from the notes to that table: no part of a cable within the containment should sit less than 10mm below the top of the barrier, and the separation for solid containment is in addition to anything provided by a divider or barrier. Annex A444 is informative, and its recommendations assume the design current in the LV circuits does not exceed 600A among other conditions — so on a large distribution basket, check the assumptions hold before leaning on the reduced figures.

Separately, Regulation 444.6.2 requires a minimum distance of 130mm between information and communications technology cables and discharge, neon and mercury vapour (or other high-intensity discharge) lamps, with low energy lamps counted as discharge sources.

07 · Installation Guide

Advantages over Solid Cable Tray

Wire basket has become the default in UK data centres, server rooms and exposed-ceiling commercial fit-outs. The reasons are practical rather than regulatory.

Airflow around the cables: The open mesh lets air circulate on all sides, which is what puts the installation in the free-air reference methods and keeps localised heat out of tightly bunched groups. In raised-floor data centres the same property keeps the under-floor plenum clear.
On-site flexibility: Cut with side cutters, crop with bolt croppers, form with the manufacturer's bending tool or over a former. No metal saw or angle grinder needed, so route changes and additions happen the same day rather than waiting on factory fittings.
Cable identification: Cables are visible from below, above and through the sides, which makes fault-finding and later additions far quicker than in enclosed conduit or lidded trunking. In data centres the same basket carries overhead power distribution and Cat6/Cat6A structured cabling on separate runs.
Gentler on cable sheaths: Round wire presents a smooth surface to the sheath. Cut sections of pressed steel tray leave sharp edges that need dressing before cables are pulled over them.
Appearance: Exposed-services ceilings are commonly specified with wire basket rather than solid tray, and it is available in powder-coat finishes for projects where the services are part of the architecture.

08 · Installation Guide

Cost vs Solid Cable Tray

Wire basket generally costs more per metre in material than equivalent pressed steel perforated tray, and that premium has to be weighed against the labour saving. The figures below are indicative market guidance to frame the trade-off — they are not a quote, and installed cost varies by project, route complexity and supplier.

Factor	Wire basket vs perforated tray
Material cost per metre	Typically ~20–40% higher than equivalent HDG perforated tray
Installation labour	Often ~15–30% lower on complex routes — on-site cutting and bending, clip-on earth bonds, faster cable laying
Programme	Faster on fast-track fit-outs; routes adapt on site without waiting for factory fittings
Where tray still wins	Long straight runs, cables needing protection from below, fixed routes that will not change

On a large project with hundreds of metres the material premium is real, but the labour and programme savings can partially or fully offset it — so compare on a project-specific installed-cost basis rather than headline material price. Where routes are long, straight and unlikely to change, pressed steel solid-bottom or perforated tray is often better value. See the cable tray installation guide for the direct comparison.

09 · Installation Guide

For Electricians: Certifying Wire Basket Installations

Commercial work on basket needs the same certification as any other installation: earth continuity of the containment verified and recorded under Regulation 643.2.1, the grouping factors actually applied to the cable sizing, and power/data separation evidenced. Record the continuity readings on the schedule of test results rather than leaving them as a tick.

In the app

Complete commercial installation certificates on your phone

Record test results, earth continuity readings and circuit details on site with the Elec-Mate EIC and EICR apps, and generate the PDF before you leave.

Try it free for 7 days

Frequently Asked Questions About Wire Cable Basket

What electricians say

Verified reviews from the UK App Store.

One App for Everything!

Elec-Mate is my go to app for business and electrical work. It's feature rich without feeling cluttered. A true all in one app for quotes, certs, calculations, RAMS, EICRs, and more. I use it every day without fail, and it makes my workflow much smoother since I'm not jumping between apps anymore. The price-to-feature ratio is excellent. Any issues I've had, the developer responds within the hour and usually fixes them the same day. 100% recommend.

Fantastic app for electricians

I've used the app and the web based version for a while now and it's well worth the investment. If you're an apprentice or experienced Spark give it a go, you won't be disappointed.

Absolutely amazing

I've been using Elec-Mate for a while now, and honestly, it's one of the best apps I've ever downloaded. Every aspect of it feels thoughtfully designed, from the clean and intuitive interface to the powerful features that make everything so easy to manage. It's clear that a lot of care and attention went into building this app, and it shows in every detail.

Trusted by electricians across the UK

Real feedback from real sparks

“Replaced three separate apps with Elec-Mate. Certs, quotes, and scheduling all in one place.”

Daniel Palmer

Sole Trader · DP Electrical

“I've won two contracts this month because I could turn quotes around same-day with the AI cost engineer.”

Nathan Perry

Electrician · NP Electrical Services

“The study centre got me through my AM2. Mock exams and flashcards are brilliant.”

Jake Pizey

3rd Year Apprentice · Apprentice

7-day free trial

Complete Commercial Certificates on Your Phone

Join 1,000+ UK electricians using Elec-Mate to certify commercial cable basket installations on site. Record test results and earth continuity — instant PDF export. 7-day free trial.

Start your free trial

From £6.99/mo after the trial — no charge until day 8.