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