First Fix vs Second Fix Electrics UK — What Each Stage Covers and How to Price Electrical Work in New Builds and Renovations (2026)

What first fix and second fix mean — and why the distinction matters for quoting

The terms come from the sequence of construction work on any new build or major renovation. First fix covers everything that goes inside walls, floors and ceilings before they are closed up — all the hidden infrastructure. Second fix covers everything that gets fitted and connected after walls are plastered and dried out — all the visible hardware and live connections.

The distinction matters commercially because the two stages happen weeks or months apart on a build programme. If you quote a single combined price at the outset and the build runs over, you end up waiting for your second-fix payment while materials and labour costs have moved on. Quoting them separately — even on a combined contract — gives you clear payment milestones, makes it easier to manage variations (a client who changes socket positions between stages) and lets you price each stage according to the actual risk and complexity of the work.

On renovation jobs, the distinction is just as important. A client whose plasterer delays by six weeks expects the electrician to pick up where they left off at the agreed second-fix price — even if material costs have risen or your diary has changed. A clear two-stage quote with defined trigger points avoids that conversation.

First fix electrics: what it covers

First fix is everything that must be done before the plasterer goes in. On a new build this means before plasterboard is fixed; on a renovation it means before re-plastering or dry-lining begins. The golden rule is that first fix must be complete and signed off before any surface is closed up, because revisiting it afterwards means opening walls.

• Back boxes in walls and ceilings — single and double metal or dry-lining back boxes installed to finished-wall depth, positioned to the agreed socket and switch layout drawing. Getting these right at first fix avoids costly remediation — a box set too deep or too proud cannot be corrected without replastering.
• Cable routes — chasing channels into blockwork or brick, clipping cable to timber studwork, threading through joists. In solid-floor properties this includes conduit in screed runs. Cable must be clipped at correct intervals to current BS 7671 requirements and routes must not create a future fixings hazard (marked on an as-installed drawing).
• Consumer unit position and earthing arrangements — the distribution board location is agreed at survey stage. At first fix, the main tails route from the meter position is confirmed, earthing arrangements (TN-S, TN-C-S or TT) are established, and any temporary supply arrangements for the build phase are organised with the DNO.
• Fire alarm, data and CCTV cables (where specified) — Category 6 data cabling, fire alarm cable runs (FP200 or MICC where required by the fire strategy), CCTV coax or IP cable drops and speaker/AV cabling all go in at first fix. On smart home specifications this can represent a significant proportion of first-fix labour — agreed upfront, not as a variation.
• Underfloor heating wiring — the supply cable and thermostat back box for electric underfloor heating systems are a first-fix item; the heating mat itself goes in with the floor finish at a later stage. Confirm with the floor finish contractor who is responsible for mat installation.
• Junction boxes in ceiling voids — where lighting circuits use junction boxes rather than loop-in at the ceiling rose, these are fixed and connected at first fix in the ceiling void before boards go up. Loop-in ceiling roses at second fix are generally preferable because junction boxes become inaccessible.
• EV charger supply cable — running a 6mm or 10mm cable from the consumer unit to the garage or driveway position at first fix, when walls are open, costs a fraction of what surface-mounted trunking adds later.

First fix must be signed off before plastering begins. On a managed build, this is often a formal checkpoint — the main contractor or project manager signs a completion notice before releasing the plasterer. On a self-managed renovation, it is your responsibility as the electrician to confirm in writing that first fix is complete and ready for closing up.

Second fix electrics: what it covers

Second fix begins after plastering is complete and the plaster has dried out sufficiently — typically four to six weeks after wet plaster, or as little as one to two weeks for dry-lining. The property needs to be at a stage where sockets, switches and consumer unit can be fitted without being immediately covered by another trade.

• Sockets, switches and pendants — fitting faceплates to back boxes, connecting all the cables pulled through at first fix, hanging pendant ceiling roses and fitting downlight trims. This is the most visible and time-consuming part of the second fix on large jobs — a 4-bed property with double sockets throughout and feature lighting will have 60–90 individual accessory connections.
• Consumer unit installation and circuit connection — the distribution board is mechanically fixed, all circuit cables terminated, RCBOs or MCBs fitted to the correct ratings and the main earthing and bonding completed. On a new build this is done before power-up; on a renovation replacing an old board the existing circuits are connected to the new unit.
• Kitchen appliance connections — cooker or hob connection (typically a 45A cooker switch and connection unit or a direct 6mm feed to the appliance terminal block), dishwasher spur, washing machine spur, integrated fridge supply and extractor fan. Kitchen second fix is the most complex room on any renovation project — coordinate with the kitchen fitter on the sequence of works.
• Bathroom connections — shaver socket installation (shaver supply units must meet BS EN 61558 for use in Zone 2 of bathrooms), extractor fan wiring, heated towel rail timeswitch or thermostat, electric shower connection where applicable. All bathroom wiring must comply with the zone requirements of BS 7671 Chapter 70.
• Smoke and heat detectors, CO alarms, doorbell — interlinked mains smoke alarms are a second-fix item; the wiring runs were completed at first fix. A Grade D, Category LD2 installation to BS 5839-6 is standard for most domestic properties. Video doorbells and wired intercom systems are also connected at second fix.
• EV charger final connection — fitting the charge point unit to the pre-wired supply, commissioning the OLEV-approved charger and completing any required registration with the manufacturer for smart charging compliance.
• Smart home commissioning (where applicable) — fitting smart switches, dimmer modules, hub equipment and carrying out initial pairing and configuration. This is frequently underestimated at quote stage — allow substantial time if this is a fully integrated smart home specification.

Pricing electrical work: per room and whole-house rates

Electrical pricing in 2026 is typically structured as either a per-room rate for smaller jobs or scoped renovation rooms, or a whole-house labour-only figure for full new build and whole-house renovation packages. Materials are almost always priced separately at cost-plus or agreed at a fixed materials allowance.

Per-room pricing (labour only, first and second fix combined):

Whole-house labour (first fix + second fix, excluding materials and certification):

The wide ranges reflect regional variation — London and the South East sit at the top; the North of England, Wales and Scotland at the lower end. They also reflect the difference between a standard new build spec and a high-spec renovation with feature lighting, smart home integration and premium accessories throughout.

What affects the price of electrical work

Several factors push electrical quotes above or below the standard ranges. Understanding these allows you to justify your price clearly in a quote and avoid being undercut by someone who has simply missed the complexity:

• Property age and rewire requirement — on a renovation of a pre-1970s property, first fix includes stripping out the old rubber or cloth-insulated wiring before laying new cables. This adds a day or more of labour per floor and must be priced separately. Never absorb old cable stripping into a standard first-fix rate.
• Ceiling height — rooms above 2.7m require podium steps or a tower scaffold for fitting downlights and ceiling accessories. This is slow work and should be allowed for in your rate. Victorian properties with 3m+ ceilings can add 20–30% to second-fix labour in those rooms.
• Plaster type — chasing hardwall plaster (sand and cement scratch coat) is significantly harder than chasing lightweight gypsum. On solid-wall properties with original hardwall plaster, allow more time for first-fix chasing and factor in that the chases will need to be made good by a plasterer rather than simply filled.
• Floor construction — timber suspended floors allow cables to be dropped through joists relatively easily. Solid concrete floors mean all cables must be chased into the screed or walls, or surface-mounted in conduit. This affects both routing time and the neatness of the finished installation.
• Smart home integration — a property specified with smart lighting control (Lutron, KNX, Loxone), multi-room audio, whole-home networking and integrated AV can triple the first-fix cable volume and add days to second fix for pairing, programming and commissioning. Always get the smart home specification in full before quoting.

Part P compliance: when you self-certify and when you need Building Control

Part P of the Building Regulations (England and Wales) requires that notifiable electrical work in dwellings is either carried out by a registered Competent Person or notified to the local authority Building Control before work starts. Understanding which route applies to which type of work is essential for protecting your business and your clients.

Notifiable work includes: installation of a new circuit, replacement of a consumer unit, any work in a special location (bathroom, kitchen, garden, garage), and any work in a new build or extension. In practice, almost all first-fix and second-fix electrical work in new builds and renovations is notifiable.

• NICEIC or NAPIT registered electrician (self-certification route) — if you are a registered member of a Competent Person Scheme such as NICEIC or NAPIT, you self-certify the work, issue an Electrical Installation Certificate (EIC) or Minor Electrical Installation Works Certificate (MEIWC) as appropriate, and the scheme notifies Building Control on your behalf. There is no additional cost to the client and no delay waiting for a Building Control inspection. This is the standard route for professional domestic electricians and the one you should be on if you are not already.
• Local Authority Building Control — non-registered electricians, or property owners doing their own work, must notify the local authority before work starts. LABC will arrange an inspection and charge a fee (typically £200–£400). This adds time and cost and leaves the client without a certificate until after inspection. Not recommended as a long-term operating model.

In Scotland, the relevant legislation is Part 4 of the Building (Scotland) Regulations and compliance is via SELECT or NICEIC registration. In Northern Ireland, compliance follows the Building Regulations (Northern Ireland) 2012.

On completion, the client must receive the EIC — a legal document that travels with the property and is required by conveyancers on sale. Without it, the work is technically unverified and can delay or kill a property transaction. Make it clear in your quote that the EIC is included and what it means.

Third fix: the stage that gets forgotten on quotes

Most electricians quote first fix and second fix. Far fewer explicitly quote third fix — the commissioning, testing and certification stage that turns a completed installation into a verified, certifiable, handed-over job. On small jobs this is absorbed into second fix without comment; on large new builds and renovations it is a distinct, billable event.

• Full inspection and testing — continuity tests, insulation resistance tests, polarity checks and earth fault loop impedance testing on every circuit. On a 4-bed new build with 16+ circuits this takes the best part of a day for one electrician. It is skilled, time-consuming work and should not be given away.
• EICR or EIC issue — an Electrical Installation Condition Report (EICR) is issued on existing installations; an Electrical Installation Certificate (EIC) is issued on new installations. Both are legal documents. The EIC for a new installation confirms the work complies with BS 7671 at the date of completion.
• Smart home commissioning — on smart-spec properties, commissioning is a separate event: pairing devices, programming scenes, setting up the app, testing voice control integration and handing over to the client. This alone can take a full day on a complex installation.
• Customer handover — walking the client through the consumer unit, explaining the circuits, demonstrating the smoke alarm test procedure, handing over the EIC and any appliance documentation. Do this in person, not via email, and allow an hour for a typical residential job.

Third fix should appear as a line item in your quote. Even if you do not charge extra for it separately, naming it makes clear that testing and certification are included — and sets the expectation that this is the final stage before the final invoice.

How to structure an electrical quote for new builds and renovations

A well-structured electrical quote does three things: it wins the job, it sets clear expectations, and it protects your cash flow across a project that may run for months. Here is the structure that works on new build and whole-house renovation electrical packages:

Quote structure:

• Scope of works — specific description of what is included at each stage. Reference the agreed drawing or schedule of sockets and lights. Do not write vague descriptions like “all electrical works” — write “first fix to all rooms as per schedule of sockets and lights dated [date], including back boxes, cable routes, consumer unit position and earthing.”
• Exclusions — be explicit about what is not included. Redecoration, making good after chasing, supply of light fittings, smart home programming beyond initial setup. Exclusions prevent disputes.
• Materials — either a fixed materials allowance (specify the consumer unit brand and grade of accessories) or a cost-plus arrangement with an agreed markup. Never leave materials ambiguous — a client who later discovers your quote did not include the consumer unit will feel misled.
• Certification — confirm that an EIC and Part P notification through your Competent Person Scheme registration is included. This is a selling point, not an afterthought.

Payment terms for staged electrical works:

The standard payment structure for a new build or full renovation electrical package in 2026 is a three-stage payment that mirrors the construction stages:

• 30% on first fix completion — payable when all cables are in, back boxes are set and the installation is signed off as ready for plastering. This payment covers materials already purchased and labour already completed before you are off-site for weeks.
• 40% on second fix completion — payable when all accessories are fitted, the consumer unit is connected and the installation is functionally complete. This is the largest payment and typically the point at which the client gets power.
• 30% on commissioning and certification — payable when testing is complete, the EIC is issued and the client handover has taken place. Retaining 30% to commissioning incentivises prompt access for testing and ensures you are paid for the third-fix work.

Avoid agreeing to a single payment at the end of the job. On a 12-week project, that means funding three months of labour and materials before you see any money. Stage payments are industry standard on any project over £2,000 and no professional client should object to them.

Whether to issue separate quotes for first fix and second fix or a single combined quote depends on the client and the project. On a developer or contractor-managed build, a single combined quote with split payment milestones is clean. On a direct-to-homeowner renovation where the scope may change significantly between stages, separate quotes give you more flexibility to reprice if the spec changes.