What Is Involved in a Full House Rewire in Portsmouth?
Portsmouth’s housing stock makes the house rewire question more relevant here than in almost any comparable city in southern England. The city sits on Portsea Island — one of the most densely populated islands in the country — and the overwhelming majority of its residential properties are Victorian and Edwardian terraces. Southsea, Fratton, North End, Buckland, Copnor and the streets running inland from the seafront are almost entirely made up of two and three-storey terraced properties built between roughly 1860 and 1910. Hundreds of thousands of these properties are still standing and still occupied. Many carry electrical installations that have been modified repeatedly over the decades without ever being comprehensively reassessed.
A house rewire is the most significant single electrical project most Portsmouth homeowners will undertake — and the one where understanding what the process actually involves is most useful before work starts. This post walks through the full rewire process from the initial assessment through to certification and completion, explains what the work involves at each stage, and covers the specific considerations that apply to Portsmouth’s predominant property type.
Why Portsmouth Properties Often Need Rewiring
The Victorian and Edwardian terraces of Southsea, Fratton and the wider Portsea Island housing stock share a consistent set of electrical characteristics. Properties built before 1914 were not designed with electricity in mind — it was typically added later, often in the 1930s or 1940s, using wiring methods and materials that are now well past their service life.
Rubber-insulated cables from this era — the standard wiring type used across Portsmouth’s post-war electrical installations — deteriorate over time. The rubber insulation becomes brittle and prone to cracking, exposing live conductors. Consumer units from the same era provide no RCD protection whatsoever — the circuit protection that has been mandatory in new installations since 2008 and that significantly reduces the risk of fatal electric shock.
Beyond the age of the installation itself, Portsmouth’s high proportion of rented and HMO properties has led to electrical installations being modified repeatedly by different hands over many decades. An original 1940s installation in a Southsea terrace may have had circuits added for storage heaters, an electric shower, a kitchen extension and a loft conversion — each addition carried out at different times, to different standards, with no single assessment ever reviewing the installation as a whole.
An EICR — Electrical Installation Condition Report — is the way to establish the true condition of the installation. For landlords in Portsmouth, EICRs every five years are a legal requirement. For owner-occupiers, particularly those who have recently purchased a Victorian or Edwardian terrace and do not know its full electrical history, an EICR is the rational starting point before deciding whether a full rewire or targeted remedial work is the right response.
Stage 1 — The Pre-Rewire Assessment
A full house rewire starts before any work is carried out on site. The assessing electrician surveys the property to establish the existing circuit layout, the condition of any wiring that might be retained, the earthing and bonding arrangements, and the specification of consumer unit that will be needed for the new installation.
On a Portsmouth Victorian terrace the assessment also covers the practical questions that affect both the cost and the programme. Where is the consumer unit currently located, and does it need to move? What are the cable routes available through the property — ceiling voids, floor voids, internal walls — and are there any that are inaccessible without more significant making good? Is the incoming mains supply adequate for the property’s current and anticipated electrical demand, particularly where EV charging, heat pumps or higher electrical loads are being considered?
The assessment gives the basis for a fixed, itemised quote. On Portsmouth’s Victorian terraces, where no two properties are identical in terms of internal layout, conversion history and the extent of previous modifications, visiting the property before quoting is essential.
Stage 2 — Preparation and Enabling Works
Before first fix cabling begins, the property is prepared. Furniture is moved out of working areas or protected in place. Where flooring needs to be lifted — suspended timber ground floors are standard across most of Portsmouth’s older terraced housing — boards are carefully lifted and labelled for relaying in the correct order. On properties where lath and plaster ceilings are still present — common in the older rooms of Southsea and Fratton terraces — access for ceiling-mounted cables requires more care than on properties with plasterboard.
For occupied properties, the programme is managed around the household’s daily routine. The property will be without power for extended periods during the rewire — typically arranged to coincide with occupied working hours where possible. Most households find it practical to make alternative arrangements for the duration of the main rewire phase, which on a standard Portsmouth terrace typically runs five to eight days.
Stage 3 — First Fix Cabling
First fix is the main body of the rewire — running new cables throughout the property to every socket, switch, light fitting, and fixed appliance connection. Every circuit in the rewired installation is new. All existing cables are removed or isolated.
On a Portsmouth Victorian terrace, the cable routes typically used are:
— Ceiling voids — cables for ground floor lighting and first floor socket and lighting circuits are routed through the ceiling void above the ground floor, accessed from above where possible.
— Floor voids — the suspended timber ground floor provides an accessible run for cables to ground floor sockets and fixed appliances. Boards are lifted, cables are clipped to joists beneath the floor, and boards are relaid on completion.
— Internal walls — cables that cannot be routed through voids are chased into plaster in channels cut into the wall surface. On Portsmouth’s Victorian brick-built terraces with solid internal walls — common throughout the older housing of Fratton and Buckland — more chasing is required than on properties with stud internal walls.
— Stair and landing routes — multi-storey terraces route cables vertically between floors through the staircase void or within internal wall cavities. Portsmouth’s three-storey Southsea terraces have more complex vertical cable distribution than the standard two-storey stock.
A qualified local electrician works systematically through each floor and each circuit in sequence. On a standard three-bedroom Portsmouth terrace, first fix typically runs four to six days depending on the circuit count and the accessibility of cable routes.
Stage 4 — Consumer Unit Installation
The new consumer unit is installed as part of the rewire — a modern metal-enclosed unit with individual RCBO protection on every circuit. An RCBO combines the functions of an MCB (protecting against overload and short circuit) and an RCD (protecting against earth fault and shock risk) in a single device for each circuit. A fault on any one circuit trips that circuit and only that circuit — the rest of the installation remains live.
Since 2016, all new domestic consumer units in England are required to be metal-enclosed — a fire safety requirement addressing the risk that a plastic unit could ignite and spread fire. Any rewire quote specifying a plastic consumer unit is not compliant with current regulations.
The consumer unit position matters on Portsmouth’s Victorian terraces. The original position — frequently in a hallway cupboard or under the stairs — is usually retained where it suits the new installation. Where the mains supply enters the property from the front and the new installation would benefit from a different position, the supply cutout location and meter position may also require discussion with the network operator.
Stage 5 — Making Good
First fix leaves the property with lifted floorboards, chased walls and in some cases disturbed ceiling surfaces. Making good returns all surfaces to a condition ready for decoration — boards relaid, wall channels filled and skimmed, ceiling penetrations filled and made flush.
The extent of making good is one of the most variable elements of a Portsmouth rewire in terms of both time and cost. On properties with plasterboard internal walls and accessible ceiling voids, making good is relatively contained. On the solid-walled Victorian terraces of central Portsmouth with lath and plaster ceilings and brick internal walls, the chasing and surface disturbance is more significant and making good takes longer.
Making good to skimming standard — filling, priming and leaving surfaces ready for decoration — is typically included in a rewire quote. Making good to full decoration standard is usually priced separately. Confirm exactly what is included at the quoting stage.
Stage 6 — Second Fix
Second fix installs all accessories — sockets, switches, light fittings, and any specialist accessories — once making good is complete and the property is ready for decoration or decoration is finished. Every circuit is connected at the accessories, the consumer unit connections are completed and the installation is ready for testing.
On Portsmouth properties where the rewire is being carried out as part of a wider renovation programme — increasingly common on recently purchased Southsea and Fratton terraces — second fix timing is coordinated with the renovation programme to avoid accessories being installed before adjacent plastering and decorating is complete.
Stage 7 — Testing, Certification and Completion
Every circuit in the rewired installation is tested against the requirements of BS 7671 — the 18th Edition of the IET Wiring Regulations. Testing covers insulation resistance on every circuit, earth fault loop impedance at every accessory position, prospective fault current at the consumer unit, RCD trip times, and polarity verification throughout.
The test results are recorded and an Electrical Installation Certificate is issued on completion. This certificate is the legal document that confirms the installation is safe and compliant — it is required for any future sale of the property and should be kept permanently with your property paperwork. The installation is also notified to building control under Part P of the Building Regulations by the registered electrician — this is a legal requirement and not optional.
How Long Does a House Rewire Take in Portsmouth?
For a standard two to three-bedroom Portsmouth Victorian terrace:
— Pre-rewire assessment and quote: one visit, same or next day quote
— First fix: four to six days
— Making good: two to four days
— Drying time before second fix: two to five days depending on the extent of plastering
— Second fix: one to two days
— Testing and certification: one day
Total on-site programme: ten to sixteen working days on a standard property. Three-storey Southsea terraces with higher circuit counts and more complex cable routes sit toward the upper end of this range.
If you own a Victorian or Edwardian terrace in Portsmouth, Southsea, Fratton, North End or anywhere across Portsea Island and want to know whether your installation is due for assessment or rewiring, get in touch and we will come out to take a look. Get in touch to arrange a visit.