By the Golbik GBS team · Blog

The consumer unit, often still called the fuse box, is the heart of a home’s electrical installation. Many London homes still have boards that were fitted long before modern safety devices became standard. This guide explains when an upgrade makes sense, what the regulations require and what happens on the day. For the wider picture, see our guide to rewiring and EICR checks.

Key takeaways

• Old fuse boxes with rewireable fuses or no RCD protection are the most common reason to upgrade.
• Since 2016, consumer units in homes must have a non-combustible enclosure, usually metal.
• A new consumer unit is notifiable work and must be tested and certified by a registered electrician.
• Faults found on existing circuits must be fixed before they are connected to the new board.
• The power is usually off for part of a day while the work is carried out.

Signs Your Fuse Box Needs Upgrading

• Rewireable or cartridge fuses instead of circuit breakers.
• No RCD protection, so there is nothing to cut the power quickly in an earth fault.
• A plastic or wooden enclosure rather than a non-combustible one.
• Frequent tripping, warm or discoloured parts, or a burning smell.
• No spare ways for new circuits for an extension, loft, kitchen or car charger.
• An unsatisfactory EICR with the board recorded as C1 or C2.

What a Modern Consumer Unit Includes

Regulations and Certificates

All work is carried out to the current edition of the wiring regulations, BS 7671. Replacing a consumer unit is notifiable under Part P of the Building Regulations, so it must either be done by an electrician registered with a competent person scheme, who can self-certify it, or be inspected by building control.

On completion you should receive an Electrical Installation Certificate and, via the scheme, a Building Regulations compliance certificate. Keep both with your property documents.

What Happens on the Day

1. Testing the existing circuits – faults such as poor insulation or missing earths must be fixed before they can be connected to RCD protection, otherwise the new board will trip.
2. Isolating the supply – the power is switched off at the main switch; if the main fuse itself needs work, the network operator is involved.
3. Fitting the new board – the old unit is removed, the new one installed and circuits labelled clearly.
4. Testing and certification – every circuit is tested and the results recorded on the certificate.

Upgrading as Part of a Bigger Project

If you are planning an extension, a loft conversion or a full refurbishment, it is usually best to upgrade the consumer unit as part of that work, when new circuits are being added anyway. Homeowners near our base can also see our Wallington and Carshalton area guide.

Frequently Asked Questions

How do I know if my consumer unit needs replacing?

Common signs are rewireable or cartridge fuses, no RCD protection, a plastic or wooden board, frequent tripping, scorch marks, or an EICR that records the board as unsatisfactory. Adding new circuits, such as for an extension or an electric car charger, can also mean the board needs upgrading.

Is a consumer unit replacement notifiable under Building Regulations?

Yes. Replacing a consumer unit is notifiable work. A registered electrician can self-certify it and issue an Electrical Installation Certificate, and the work is registered with building control.

Will the power be off all day?

The supply is switched off while the old board is removed and the new one connected and tested, which usually takes part of a working day. Plan for no power for several hours.

What if the main fuse also needs changing?

The main fuse and cut-out before the meter belong to the network operator, which is UK Power Networks in most of London. If they need replacing or the supply needs isolating at that point, the network operator must be involved.

Need a Consumer Unit Upgrade?

Golbik GBS replaces consumer units, rewires homes and carries out electrical upgrades across London, with work tested and certified. See our domestic electrical services, our electricians in Mitcham, or contact us.

Related Guides

• Full House Refurbishment in London: Stages, Permissions and Timeline
• Loft Conversion Types for London Homes
• Side-Return, Rear or Wraparound Extension?
• Planning a Kitchen Renovation in a London Home
• Bathroom Renovation in London: Wet Rooms, Waterproofing and Safety Zones
• Does Your London Home Need Rewiring?
• Upgrading Heating and Plumbing in an Older London Home
• Party Wall Agreements in London: A Homeowner’s Guide
• Do You Need Planning Permission? Rules by London Borough
• Extending a 1930s Semi in Sutton, Wallington and Mitcham
• Renovating a Victorian Terrace in South West London
• How to Choose a Builder in London

By the Golbik GBS team · Blog

Older London homes often have heating and plumbing that has been patched and extended over many decades: a mix of pipe sizes, old radiators, a tank in the loft and a boiler past its best. Upgrading the system can make the house warmer, cheaper to run and far more reliable. This guide explains the main choices when planning plumbing and heating work in an older property.

Key takeaways

• The right heating system depends on the number of bathrooms, your water pressure and the space available.
• Combi boilers suit smaller homes with good mains flow; system boilers with a cylinder suit larger households.
• London has hard water, so scale protection for boilers and hot water systems is worth planning in.
• Homes built before around 1970 may still have lead water pipes, which are best replaced.
• Gas work must be done by a Gas Safe registered engineer and notified under Building Regulations.

Choosing a Heating System

Heat pumps are increasingly common, and government grants such as the Boiler Upgrade Scheme may be available. They work best in homes with good insulation and properly sized radiators, so they are often considered as part of a wider renovation.

Water Pressure and Flow

Low pressure is one of the most common complaints in older London homes. Before choosing a boiler or shower, it is worth measuring both the static pressure and the flow rate at the kitchen tap. Typical solutions include:

• Replacing an old, narrow or lead supply pipe with a larger modern pipe.
• Converting a gravity-fed system to a mains-pressure unvented cylinder.
• Fitting a pump to a gravity-fed shower where mains pressure is not an option.
• Rebalancing or replacing undersized internal pipework.

Hard Water and Scale

London’s water is hard, which means limescale builds up in boilers, cylinders, showers and taps. In hard water areas, Building Regulations guidance calls for scale protection on new combi boilers, and a scale reducer or water softener can extend the life of the whole system. It also keeps bathroom fittings and kitchen taps looking better for longer.

Old Pipework and Lead Pipes

Homes built before around 1970 may still have lead supply pipes, and many older houses have a mix of galvanised steel, copper and plastic pipework. Replacing old pipework during a renovation improves water quality and pressure and reduces the risk of leaks. Your water company is responsible for the pipe up to the boundary, and can advise on replacing their section at the same time.

Radiators and Underfloor Heating

Radiators

Correctly sized radiators with thermostatic valves in each room give better comfort and control. A system flush or power flush before fitting a new boiler removes sludge from older pipework.

Underfloor heating

Wet underfloor heating is ideal in a new extension, where the floor is built from scratch, and works well with heat pumps. In upper floors and loft conversions, low-profile systems are available.

Doing It at the Right Time

The best moment to renew heating and plumbing is during a full refurbishment, when floors are up and walls are open, and it is usually coordinated with the electrical work. All gas work must be carried out by a Gas Safe registered engineer.

We work on homes throughout London, including Clapham, Fulham, Chelsea, Hammersmith, Dulwich and Mitcham.

Frequently Asked Questions

Should I choose a combi or a system boiler?

A combi heats water on demand and saves space, which suits flats and smaller homes with one bathroom and good mains flow. A system boiler with an unvented cylinder stores hot water and suits homes with two or more bathrooms used at the same time.

Why is my water pressure low?

Common causes include old narrow or corroded pipework, a long or shared supply pipe, gravity-fed systems relying on a loft tank, or simply being on an upper floor. A plumber can measure pressure and flow to find the cause before recommending a pump, a new supply pipe or an unvented system.

How do I know if I have lead pipes?

Lead pipes are dull grey, soft and do not make a ringing sound when tapped, and are most likely in homes built before around 1970. Check where the supply pipe enters the house, usually under the kitchen sink. Lead pipes are best replaced, and your water company can advise on their part of the supply.

Can I have underfloor heating in an older house?

Yes. Wet underfloor heating works particularly well in new extensions where the floor is being laid from scratch. In existing rooms, low-profile systems can be fitted over existing floors or between joists.

Planning Plumbing or Heating Work?

Golbik GBS carries out plumbing, heating and hot water upgrades across London, from boilers and radiators to full system replacements. See our domestic plumbing services or contact us to arrange a survey.

Related Guides

• Full House Refurbishment in London: Stages, Permissions and Timeline
• Loft Conversion Types for London Homes
• Side-Return, Rear or Wraparound Extension?
• Planning a Kitchen Renovation in a London Home
• Bathroom Renovation in London: Wet Rooms, Waterproofing and Safety Zones
• Does Your London Home Need Rewiring?
• Party Wall Agreements in London: A Homeowner’s Guide
• Do You Need Planning Permission? Rules by London Borough
• Extending a 1930s Semi in Sutton, Wallington and Mitcham
• Consumer Unit (Fuse Box) Upgrades Explained
• Renovating a Victorian Terrace in South West London
• How to Choose a Builder in London

By the Golbik GBS team · Blog

Many London homes still run on wiring installed decades ago, long before kitchens full of appliances, home offices and electric car chargers. Ageing wiring is not always obvious, but it can be a fire and shock risk. This guide explains the warning signs, how an inspection works and what to expect if your home needs rewiring or electrical upgrades.

Key takeaways

• Old cable types, a fuse box with rewireable fuses and no RCD protection are common signs a home needs attention.
• An Electrical Installation Condition Report (EICR) is the professional way to assess an existing installation.
• Owner-occupiers are advised to have an EICR at least every 10 years; private landlords in England need one every 5 years.
• Rewiring is easiest during a refurbishment, when floors and walls are already open.
• New circuits and rewires are notifiable work and should come with an Electrical Installation Certificate.

Warning Signs Your Wiring Needs Attention

• Old cable types: rubber, lead-sheathed or fabric-covered cables, typically found in installations from before the 1970s.
• An old fuse box: rewireable fuses, a wooden back board or a mix of old and new parts.
• No RCD protection: modern installations protect circuits with residual current devices that cut the power in a fault.
• Physical signs: scorch marks, warm or buzzing sockets and switches, flickering lights, a burning smell.
• Frequent tripping or fuses blowing.
• Too few sockets and heavy reliance on extension leads.

What Is an EICR?

An Electrical Installation Condition Report is a detailed inspection and test of an existing installation, carried out by a qualified electrician. It checks wiring, earthing and bonding, protective devices, sockets and fittings, and records any defects with a classification code:

For owner-occupied homes, an EICR is recommended at least every 10 years and when buying a property. Private landlords in England must have one at least every 5 years and provide a copy to tenants.

Partial or Full Rewire?

Consumer unit upgrade

If the wiring itself is sound but the fuse box is outdated, replacing it with a modern consumer unit with RCD protection can be enough. Since 2016, consumer units in homes must be made of non-combustible material, typically metal.

Partial rewire

Individual circuits, such as the kitchen or an extension, can be renewed while the rest of the installation is kept, provided the existing wiring tests satisfactorily.

Full rewire

Where cables are old or the installation is unsafe, a full rewire replaces all cables, accessories and the consumer unit. It is most efficient during a full refurbishment, when floors and walls are open and plastering follows anyway.

What Happens During a Rewire

1. Planning: agree positions for sockets, switches, lighting, data points and appliances.
2. First fix: floorboards lifted and walls chased to run new cables to every point.
3. Making good: walls and ceilings plastered, floors relaid.
4. Second fix: sockets, switches, lights and the consumer unit connected.
5. Testing and certification: the installation is tested and an Electrical Installation Certificate issued, with the work notified under Building Regulations.

If you are also planning a new kitchen, bathroom, extension or loft conversion, plan the electrics as part of that project rather than separately.

Rewiring Period Homes in London

Victorian and Edwardian houses often have suspended timber floors, which make running new cables easier, but also original plaster and features that need careful handling. Converted flats can have shared or confusing supplies that need tracing before work starts.

We carry out electrical work across London, including Clapham, Fulham, Chelsea, Hammersmith, Dulwich and Mitcham.

Frequently Asked Questions

How do I know if my house needs rewiring?

Warning signs include rubber, lead or fabric-covered cables, a fuse box with rewireable fuses, no RCD protection, scorch marks or warm sockets, frequently tripping circuits and too few sockets for modern use. An EICR carried out by a registered electrician will confirm the condition of the installation.

What do the codes on an EICR mean?

C1 means danger present and immediate action is required. C2 means potentially dangerous and urgent remedial action is required. C3 means improvement recommended. FI means further investigation is needed. A report with any C1, C2 or FI codes is classed as unsatisfactory.

How often should an EICR be done?

For owner-occupied homes, an inspection at least every 10 years is recommended, and when buying a property. Private landlords in England are legally required to have the installation inspected at least every 5 years.

How long does a full rewire take?

It depends on the size of the property and whether it is occupied. A typical house rewire takes from several days to a couple of weeks, followed by making good and decoration. Rewiring an empty property during a refurbishment is quicker and less disruptive.

Need an Electrician?

Golbik GBS carries out rewiring, consumer unit upgrades, lighting and electrical alterations across London, with work tested and certified. Visit our domestic electrical services page or contact us to arrange a visit.

Related Guides

• Full House Refurbishment in London: Stages, Permissions and Timeline
• Loft Conversion Types for London Homes
• Side-Return, Rear or Wraparound Extension?
• Planning a Kitchen Renovation in a London Home
• Bathroom Renovation in London: Wet Rooms, Waterproofing and Safety Zones
• Upgrading Heating and Plumbing in an Older London Home
• Party Wall Agreements in London: A Homeowner’s Guide
• Do You Need Planning Permission? Rules by London Borough
• Extending a 1930s Semi in Sutton, Wallington and Mitcham
• Consumer Unit (Fuse Box) Upgrades Explained
• Renovating a Victorian Terrace in South West London
• How to Choose a Builder in London