By the Golbik GBS team · Blog

Choosing the right builder matters more than almost any other decision in a renovation. A good builder keeps the project safe, on schedule and within budget; the wrong one can cost far more than the price difference between quotes. This checklist covers what to check before you sign.

Key takeaways

• Check the company, its insurance and independent reviews before inviting quotes.
• Ask for registrations that cover specialist work: NICEIC or similar for electrics, Gas Safe for gas.
• Compare itemised written quotes based on the same specification, not just the total.
• Agree a written contract and stage payments linked to completed work, not large sums upfront.
• Be wary of cash-only deals, pressure to decide quickly and quotes far below the others.

Before You Ask for Quotes

• Check the company – a limited company can be looked up on Companies House to confirm its registered address, directors and how long it has traded.
• Read independent reviews – look for a track record on platforms such as Checkatrade and Google, ideally with recent jobs similar to yours.
• Ask about insurance – public liability insurance as a minimum, and ask to see the certificate.
• Check registrations – NICEIC or a similar scheme for electrical work, Gas Safe for any gas work.
• Ask about waste – builders removing waste should hold a waste carrier registration with the Environment Agency.

Questions to Ask Every Builder

Comparing Quotes

Give every builder the same drawings and specification. Compare itemised quotes line by line, check what is described as a provisional sum, and ask about anything that appears in one quote but not another. The cheapest total is often the one with the most exclusions. Our full refurbishment guide explains what a complete scope of work usually includes.

Contracts and Payments

• Use a written contract; for larger domestic projects, standard forms such as the JCT contract for homeowners are widely used.
• Agree stage payments linked to completed work, with a small retention until snagging is finished.
• Record changes in writing, with the cost agreed before the work is done.
• Make sure approvals are in place: planning or permitted development, Party Wall agreements and Building Regulations. See planning rules by borough.

Red Flags

• Cash-only payment or a discount for paying without a receipt.
• Pressure to sign the same day or to pay most of the price upfront.
• No business address, company details or written quote.
• A price far below the other quotes with little detail.
• Reluctance to provide insurance details, registrations or references.

Frequently Asked Questions

How many quotes should I get?

Three is a sensible number for most projects. Give every builder the same drawings and specification so the quotes can be compared like for like.

How much deposit should I pay a builder?

Avoid paying a large sum upfront. A modest deposit for materials or scheduling may be reasonable, with the rest paid in stages as agreed parts of the work are completed.

How can I check an electrician or gas engineer?

Electricians registered with a competent person scheme such as NICEIC can be checked on the scheme’s register, and gas engineers on the Gas Safe Register. Ask to see the relevant card or registration number.

What are my rights if I sign a contract at home?

For contracts agreed at your home, consumers usually have a 14-day cancellation period. Under the Consumer Rights Act 2015, services must also be carried out with reasonable care and skill.

How We Approach Your Project

Golbik GBS Ltd is a registered company (Companies House 12142749), has been on Checkatrade since 2016 with a rating of 9.8 out of 10 from 130 reviews, and our electrical work is carried out as a NICEIC Domestic Installer. Read our customer recommendations, explore our full refurbishment and extension services, or request a quote.

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
• Consumer Unit (Fuse Box) Upgrades Explained
• Renovating a Victorian Terrace in South West London

By the Golbik GBS team · Blog

Victorian terraces line the streets of Clapham, Fulham, Wimbledon and much of South West London. They are solid, well-proportioned homes, but they were built with materials and methods very different from today’s. Renovating one well means understanding how it was built. For the overall sequence of a project, see our full house refurbishment guide.

Key takeaways

• Victorian terraces have solid brick walls, suspended timber floors and lime-based materials, which behave differently from modern houses.
• Damp is often caused by cement render, blocked air bricks or high ground levels rather than a failed damp-proof course.
• Original features such as cornices, ceiling roses and fireplaces can usually be restored rather than replaced.
• Old wiring and lead or iron pipework should be renewed while floors and walls are open.
• Conservation area rules in parts of Clapham, Fulham and Wimbledon affect windows, roofs and front elevations.

How Victorian Terraces Were Built

Common Problems to Look For

• Damp – often caused by cement render or pointing, blocked air bricks, leaking gutters or garden levels above the floor, rather than a failed damp-proof course.
• Timber decay in floor joists and window frames where moisture has been trapped.
• Movement – London clay and nearby trees can cause cracking, which should be assessed before redecorating.
• Old services – outdated wiring and lead or iron pipework. See our guides to rewiring and heating and plumbing upgrades.
• Poor insulation – solid walls and single-glazed sashes lose heat; internal wall insulation must be breathable to avoid condensation.

Keeping the Character

Original cornices, ceiling roses, picture rails, fireplaces and sash windows are a large part of what buyers value in a period house. Damaged plasterwork can usually be repaired or re-run, and sashes can be refurbished and draught-proofed.

Clapham, Fulham and Wimbledon Compared

• Clapham – Victorian and Edwardian terraces split between Lambeth and Wandsworth, with conservation areas around the Common. See our Clapham guide and loft conversions in Clapham.
• Fulham – long late-Victorian terraces, many converted into flats, and many conservation areas. See our Fulham guide and plumbing in Fulham.
• Wimbledon – Victorian and Edwardian terraces around South Wimbledon and the Colliers Wood borders, in the London Borough of Merton. Nearby, see our Mitcham guide.

The Right Order of Works

1. Survey, including damp, structure and services.
2. Fix the building fabric: roof, gutters, external walls and ground levels.
3. Structural work and any extension.
4. First fix of electrics, plumbing and heating.
5. Plastering, with lime where walls need to breathe.
6. Kitchens, bathrooms, joinery and restored features.
7. Decoration and final checks.

Check the planning position early in our guide to planning rules by London borough.

Frequently Asked Questions

How are Victorian terraces different from modern houses?

They usually have solid brick walls without a cavity, lime mortar and plaster, suspended timber ground floors and a rear outrigger. These materials need to breathe, so modern impermeable finishes can trap moisture.

Should I use lime or gypsum plaster?

On solid walls that suffer from damp, breathable lime-based plaster is often the better choice. Gypsum plaster is suitable on dry internal walls and new partitions. A survey of each wall helps decide.

Can I replace sash windows in a conservation area?

Often only like for like. In many conservation areas, replacing timber sash windows with a different style or material needs planning permission, so repair or draught-proofing is usually the first option.

What is a butterfly roof?

Many inner London terraces have a V-shaped roof hidden behind a front parapet, known as a London or butterfly roof. Converting it usually means a mansard, which needs planning permission.

Planning a Victorian House Renovation?

Golbik GBS carries out full refurbishments of period houses and flats across London. See our Clapham and Fulham area guides, or get in touch 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?
• 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
• How to Choose a Builder in London

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

Streets of 1930s semi-detached houses make up much of Sutton, Wallington, Carshalton and Mitcham. They were built with generous plots, hipped roofs and simple layouts, which makes them some of the most practical houses in London to extend. This guide covers the projects that suit them best and the rules that usually apply.

Key takeaways

• 1930s semis in Sutton, Wallington, Carshalton and Mitcham are among the easiest London houses to extend.
• A hip-to-gable loft conversion with a rear dormer usually adds one or two bedrooms and a shower room.
• Many of these projects fit within permitted development: 50 m³ of roof space and a 3 m (or 6 m with prior approval) rear extension.
• Most of the area sits outside conservation areas, but Carshalton Village and Mitcham Cricket Green are exceptions.
• Combine the build with electrical and heating upgrades while floors and walls are open.

What Makes a 1930s Semi Easy to Extend

• A hipped roof that can be built up into a gable to create a full-size loft room.
• A garden deep enough for a rear extension, and often a side passage or garage.
• A simple layout: front room, back room and kitchen, ideal for opening up.
• Mostly outside conservation areas, so permitted development often applies.

The Main Options Compared

Hip-to-Gable Loft Conversions

The sloping side of the roof is rebuilt as a vertical gable wall, and a dormer is usually added at the back. The new staircase normally continues above the existing one. Because the house is attached on one side, a Party Wall notice to the neighbour is almost always needed; see our Party Wall guide. Compare the alternatives in our guide to loft conversion types.

Rear and Side Extensions

A 3 metre rear extension is often permitted development, and up to 6 metres is possible through prior approval, where the council consults the neighbours. Side extensions into a passage or garage add useful space for a utility room or WC. Our guide to extension types explains the options, and planning rules by borough covers Sutton and Merton.

Upgrade the Services at the Same Time

Many 1930s houses were last rewired decades ago and still have older heating. An extension or loft is the best moment to add circuits, replace the consumer unit and resize radiators or the boiler. See our electrical work in Mitcham, plumbing and heating in Mitcham and our guide to consumer unit upgrades.

Local Councils and Protected Areas

• London Borough of Sutton – Wallington, Carshalton and Sutton. Carshalton Village is a conservation area.
• London Borough of Merton – Mitcham, Morden and Colliers Wood. Mitcham Cricket Green is a conservation area.

Frequently Asked Questions

Can I do a hip-to-gable loft conversion without planning permission?

Often, yes. On a semi-detached house outside a conservation area, a hip-to-gable conversion with a rear dormer is usually permitted development if the extra roof volume stays within 50 cubic metres and the other conditions are met. A Lawful Development Certificate confirms it in writing.

How much space does a hip-to-gable conversion add?

It typically creates room for one or two bedrooms and a shower room, depending on the size of the house and the position of the new staircase.

Can I knock the kitchen and back room together?

Yes, this is very common in 1930s houses. The wall between them is usually load-bearing, so a steel beam designed by a structural engineer and Building Regulations approval are needed.

Which council covers my house?

Wallington, Carshalton and Sutton are in the London Borough of Sutton. Mitcham, Morden and Colliers Wood are in the London Borough of Merton.

Extending a House Near You?

Golbik GBS is based in Wallington and builds loft conversions, extensions and refurbishments across Sutton, Carshalton and Mitcham. See our Wallington and Carshalton and Mitcham area guides, 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
• 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
• 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

The first question for almost every extension or loft conversion in London is whether it needs planning permission. The answer depends on the type of property, the size of the project and, very often, the street you live on. This guide explains the national rules and how they play out in the boroughs where we work.

Key takeaways

• Many house extensions and loft conversions can be built under permitted development, without a planning application.
• Permitted development does not apply to flats and maisonettes, and is restricted in conservation areas.
• Article 4 directions can remove permitted development rights on specific streets.
• A Lawful Development Certificate confirms in writing that a project is permitted development.
• Each London borough has its own conservation areas and local guidance, so the same project can be treated differently.

Permitted Development: The National Rules

Permitted development rights allow certain work on houses without a planning application, as long as the conditions are met. The most relevant ones are:

When You Will Need Planning Permission

• The house is in a conservation area and the work affects the roof, front or side.
• An Article 4 direction has removed permitted development rights on your street.
• The property is a flat or maisonette.
• The project goes beyond the limits, such as a wraparound or two-storey extension.
• The building is listed, which also needs listed building consent.
• An earlier planning condition removed permitted development rights.

Planning in the Boroughs We Work In

The national rules are the same everywhere, but conservation areas, Article 4 directions and local design guidance vary from borough to borough:

Planning Is Only One of Three Approvals

• Planning permission or permitted development – what you can build.
• Building Regulations – how it is built: structure, fire safety, insulation, drainage, electrics.
• Party Wall Act – agreement with neighbours for work to shared walls. See our Party Wall guide.

For design options, read our guides to extension types and loft conversion types, or see all the areas we cover.

Frequently Asked Questions

How far can I extend without planning permission in London?

Under permitted development, a single-storey rear extension can go up to 3 metres on a terraced or semi-detached house and 4 metres on a detached house. Through prior approval, this can be up to 6 and 8 metres, subject to the council consulting the neighbours.

Do flats have permitted development rights?

No. Flats and maisonettes do not have householder permitted development rights, so extensions, loft conversions and most external changes to flats need planning permission.

What is an Article 4 direction?

An Article 4 direction is a decision by the council to remove some permitted development rights in a specific area, often in conservation areas. Where one applies, work that would otherwise be permitted needs a planning application.

Is a Lawful Development Certificate compulsory?

It is not compulsory, but it is strongly recommended. It is the council’s formal confirmation that the work is lawful, and buyers’ solicitors often ask for it when you sell.

Not Sure What Applies to Your House?

Golbik GBS builds extensions and loft conversions across London and can help you understand the likely planning route before you commit to a design. 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?
• Upgrading Heating and Plumbing in an Older London Home
• Party Wall Agreements in London: A Homeowner’s Guide
• 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

If you live in a London terrace or semi-detached house, almost any loft conversion or extension will affect a wall you share with your neighbour. The Party Wall etc. Act 1996 sets out how that work must be notified and agreed. Getting it right early keeps the project on time and the neighbours on side.

Key takeaways

• The Party Wall etc. Act 1996 applies to most loft conversions and many extensions on terraced and semi-detached houses.
• There are three main notices: party structure (two months), line of junction (one month) and adjacent excavation (one month).
• A neighbour has 14 days to respond; silence counts as a dispute, which is resolved by party wall surveyors.
• Party wall consent is separate from planning permission and Building Regulations.
• Serving notices early and talking to neighbours first is the simplest way to avoid delays.

What Is the Party Wall Act?

The Act gives homeowners the right to carry out certain work to or near a shared wall, and gives neighbours protection while that work is done. It applies in England and Wales to party walls between houses, party structures such as floors between flats, boundary walls and excavation close to a neighbour’s foundations.

The Three Party Wall Notices

Notices must be served on every adjoining owner, which can include a freeholder and long leaseholders of flats next door, not just the person living there.

How the Process Works, Step by Step

1. Talk to your neighbours first. Explain the plans and timetable before anything arrives in writing.
2. Serve the notices. Include a description of the work, drawings where relevant and the proposed start date.
3. Wait for a response. The neighbour has 14 days to consent or dissent.
4. Consent: work can go ahead after the notice period. A schedule of condition of the neighbour’s property is still strongly recommended.
5. Dissent or no reply: surveyors are appointed, either one agreed surveyor or one each, and they prepare a Party Wall award.
6. Work starts in line with the award, and the surveyors deal with any damage claims afterwards.

Which Projects Need a Party Wall Notice?

• Loft conversions – steel beams bearing on the party wall and any raising of the wall. See our guide to loft conversion types.
• Side-return and rear extensions – new walls on the boundary and foundations close to the neighbour. See extension types compared.
• Removing chimney breasts – the chimney stack is usually part of the party structure.
• Underpinning and new foundations near a shared wall.

Minor work such as fixing shelves, re-plastering or rewiring sockets in a party wall does not normally need a notice.

Timing Your Project

Because a party structure notice needs two months, and a dispute adds time for surveyors and the award, it is sensible to serve notices as soon as the design is fixed, in parallel with planning or permitted development checks. Our guide to planning rules by London borough explains that side of the process.

Most of the houses we work on are terraces and semis. Our area guides cover Clapham, Fulham, Chelsea, Hammersmith, Dulwich and Mitcham.

Frequently Asked Questions

Do I need a Party Wall agreement for a loft conversion?

Usually, yes. Most loft conversions on terraced and semi-detached houses involve cutting into the party wall to support new steel beams or raising the wall, which requires a party structure notice at least two months before the work starts.

What happens if my neighbour does not reply to the notice?

If the adjoining owner does not respond within 14 days, a dispute is deemed to have arisen. Each side can appoint a surveyor, or both can agree on one, and the surveyors produce a Party Wall award that sets out how the work will be done.

Who pays for the party wall surveyor?

As a rule, the building owner carrying out the work pays the reasonable costs of the surveyors, including the surveyor appointed by the neighbour.

How long is a Party Wall notice valid?

A notice lapses if the work does not start within 12 months of it being served, so it should be timed with the planned start date.

Is a Party Wall award the same as planning permission?

No. The Party Wall Act deals with the relationship between neighbours. Planning permission or permitted development and Building Regulations approval are separate requirements.

Planning an Extension or Loft Conversion?

Golbik GBS builds loft conversions and house extensions across London and helps clients plan the Party Wall process into the programme from the start. Get in touch 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?
• Upgrading Heating and Plumbing in an Older London Home
• 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

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

By the Golbik GBS team · Blog

A bathroom is a small room with a lot going on behind the walls: water, waste, electrics and ventilation all have to be right before the first tile goes on. This guide covers the technical decisions that make a bathroom renovation in a London home last, from wet rooms and waterproofing to electrical safety zones and water pressure.

Key takeaways

• Good waterproofing behind the tiles matters more than the tiles themselves, especially in wet rooms.
• Bathrooms are divided into electrical zones; lights and fittings must have the right IP rating for each zone.
• Bathroom circuits need 30mA RCD protection under the wiring regulations.
• Building Regulations require mechanical extraction of at least 15 litres per second in bathrooms.
• Older London homes often have low water pressure, which affects the choice of shower and boiler.

Wet Room, Walk-In Shower or Shower Tray?

In many London flats and terraces, floors are timber joists, which move slightly. Wet rooms are still possible, but the floor needs to be stiffened and a purpose-made former or tray installed beneath the tiles.

Waterproofing: What Goes Behind the Tiles

• Tanking membrane: a liquid or sheet membrane applied to walls and floors in wet areas to stop water reaching the structure.
• Suitable boards: cement-based or waterproof boards rather than standard plasterboard around showers and baths.
• Sealed junctions: tape at corners, joints and around pipes and drains.
• Grout and silicone: good-quality materials that are maintained over time.

Poor waterproofing is the most common cause of leaks into ceilings below, so it is not the place to save money.

Electrical Safety Zones and IP Ratings

The wiring regulations divide bathrooms into zones based on how close a fitting is to water:

All bathroom circuits must be protected by a 30mA RCD. Shaver sockets must be the dedicated, isolated type. Work in bathrooms should be carried out and certified by a registered electrician, as provided by our electrical services.

Ventilation

Building Regulations require mechanical extraction in bathrooms of at least 15 litres per second. A fan with an overrun timer or humidity sensor removes moisture after showering and protects paint, grout and ceilings from mould, a common problem in older London houses with small windows.

Water Pressure in Older London Homes

Many older properties have low water pressure, especially on upper floors or with old gravity-fed systems. Options include a mains-pressure unvented cylinder, a shower pump on a gravity system or a combi boiler where mains flow is good. Hard London water also means scale protection is worth considering. Our plumbing team can test pressure and flow before you choose a shower.

Bathrooms as Part of a Bigger Project

A new en-suite is a popular part of a loft conversion, and bathrooms are often renovated alongside a new kitchen or as part of a full refurbishment.

We renovate bathrooms throughout London, including Clapham, Fulham, Chelsea, Hammersmith, Dulwich and Mitcham.

Frequently Asked Questions

Is a wet room a good idea in a London flat?

It can be, provided the floor can be laid to a fall towards the drain and the whole room is fully waterproofed. In upper-floor flats, timber floors need careful preparation, and the lease may require the freeholder’s consent for changes to waste pipes.

What IP rating do bathroom lights need?

Fittings inside the bath or shower tray (zone 0) need at least IPX7. Fittings in zone 1, directly above the bath or shower up to 2.25 metres, and in zone 2 around it typically need at least IPX4. A registered electrician will confirm the correct rating for each position.

Do I need an extractor fan in my bathroom?

Yes, for a new or renovated bathroom. Building Regulations guidance sets a minimum intermittent extract rate of 15 litres per second. Fans linked to the light or a humidity sensor help prevent condensation and mould.

Can I add a bathroom in my loft?

Usually, yes. A loft bathroom needs a waste route to the soil stack, adequate water pressure on the top floor and enough head height over the shower and toilet. It is often planned as part of a loft conversion.

Planning a New Bathroom?

Golbik GBS renovates bathrooms, en-suites and wet rooms across London, handling plumbing, electrics, waterproofing, tiling and finishing. Find out more about our bathroom renovation service in London or get in touch to discuss your project.

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
• 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
• 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

A kitchen renovation involves more trades than any other room: plumbers, electricians, joiners, plasterers, tilers and often a gas engineer and a structural engineer. In London homes, where kitchens are often narrow or tucked into a rear outrigger, careful planning makes the space work much harder. This guide walks through how to plan a kitchen renovation from layout to final fix.

Key takeaways

• Choose the layout first: it determines where pipes, drains, sockets and extraction must go.
• Electrics, plumbing and ventilation are installed before plastering, so appliance positions must be fixed early.
• Building Regulations require kitchen extraction and cover new electrical circuits, gas work and structural changes.
• Bespoke cabinets and worktops have lead times, so order them before the strip-out starts.
• Worktops are templated only after the base units are fitted.

Choosing the Right Layout

Many London kitchens are transformed by a side-return or rear extension, which turns a narrow galley into an open-plan kitchen-diner. If you are considering one, design the kitchen and the extension together.

Services: Plumbing, Electrics, Gas and Ventilation

Plumbing and drainage

Sinks, dishwashers and washing machines need water supplies and waste pipes with enough fall to the drain. Moving the sink a long way from the existing drain can mean pumps or new drainage runs. Our plumbing service covers these alterations.

Electrics

Modern kitchens need many more sockets and dedicated circuits for ovens, hobs and other appliances than older houses were built with. New circuits are notifiable work, carried out and certified by a registered electrician. See our electrical services.

Gas

Any work on gas hobs, cookers or pipework must be carried out by a Gas Safe registered engineer.

Ventilation

Building Regulations require mechanical extraction in kitchens: at least 30 litres per second for a cooker hood, or 60 litres per second for a fan elsewhere in the room. Ducting the hood to the outside wall is the most effective solution.

The Order of Works

1. Survey, design and ordering: final layout, appliances and finishes; order cabinets and long-lead items.
2. Strip-out: remove the old kitchen, flooring and damaged plaster.
3. Structural work: remove or open up walls with new beams where required.
4. First fix: new pipework, drainage, cabling, gas and extraction ducting.
5. Plastering and flooring preparation: new or repaired walls and ceilings, level floors.
6. Installation: fit base and wall units, then template the worktops.
7. Worktops, splashbacks and tiling.
8. Second fix: sink, taps, appliances, sockets and lighting connected.
9. Decoration and finishing touches.

Changing the layout after first fix is the most common cause of delay and extra cost, so it is worth taking time over the design.

Kitchens in Period Homes and Flats

Older London houses often have uneven walls and floors, which need extra preparation before units can be fitted. In flats, check the lease before moving the kitchen, as freeholders often restrict placing kitchens above bedrooms in the flat below, and changes to waste pipes may need consent.

If you are renovating in one of our core areas, see our guides to Clapham, Fulham, Chelsea, Hammersmith, Dulwich and Mitcham.

A kitchen is often part of a larger project such as a full refurbishment, and many clients renovate their bathrooms at the same time.

Frequently Asked Questions

How long does a kitchen renovation take?

Once materials are on site, the installation of a typical kitchen takes a few weeks, from strip-out to final fix. Bespoke cabinetry and stone worktops add lead time beforehand, and structural work such as removing a wall adds time on site.

Do I need Building Regulations approval for a new kitchen?

Replacing units like for like does not usually need approval. New electrical circuits, gas appliances, drainage changes, removing a load-bearing wall and new extraction all fall under Building Regulations, and are signed off by registered installers or building control.

How powerful should a kitchen extractor be?

Building Regulations guidance sets a minimum extract rate of 30 litres per second for a cooker hood over the hob, or 60 litres per second for an extract fan positioned elsewhere in the kitchen. Ducting to the outside is far more effective than a recirculating hood.

Can I move my kitchen to another room?

Often, yes, but it depends on getting a waste pipe to the soil stack or drain with enough fall, and on ventilation and gas routes. This should be checked at the survey stage.

Planning a New Kitchen?

Golbik GBS renovates and installs kitchens across London, coordinating plumbing, electrics, structural work, cabinetry, worktops, tiling and decoration. See our kitchen renovation service in London or contact us to discuss your kitchen.

Related Guides

• Full House Refurbishment in London: Stages, Permissions and Timeline
• Loft Conversion Types for London Homes
• Side-Return, Rear or Wraparound Extension?
• 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
• Consumer Unit (Fuse Box) Upgrades Explained
• Renovating a Victorian Terrace in South West London
• How to Choose a Builder in London