New Build Plumbing Services in London

Getting the plumbing right on a new build isn’t something you leave to chance. Whether you’re a developer working on a residential scheme, a self-builder managing your own project, or a homeowner extending your property, the plumbing system you install today will define the performance, safety, and maintenance costs of that building for decades to come. At Catalyst Home Services, we provide complete new build plumbing across London — from the first pipe in the ground to the final tap being turned on. Get in touch to discuss your project or call us on +44 7400 265421.

What Does New Build Plumbing Cover?

New build plumbing is the process of designing and installing an entire plumbing system from scratch in a property that doesn’t yet have one. It’s quite different from repair or maintenance work — it requires careful planning, precise sequencing alongside other trades, and a thorough understanding of the building regulations that govern how plumbing systems must be built in the UK.

A complete new build plumbing package typically covers:

  • First fix plumbing — all the pipework, drainage runs, and structural elements that go in before plastering and finishing. This is where the bones of your plumbing system are laid.
  • Second fix plumbing — the connection and fitting of all visible fixtures and appliances once decorating is complete. Taps, toilets, showers, radiators, hot water cylinders, and boilers are all connected at this stage.
  • Hot water and heating system installation — sizing and fitting the hot water system, including the cylinder or boiler, in line with the property’s demand and layout.
  • Drainage and waste pipework — soil stacks, waste runs, and connections to the mains drainage or private drainage system.
  • Testing and commissioning — pressure testing all pipework, checking drainage falls, and commissioning the hot water and heating system before handover.

Our installation services cover the full scope of new build plumbing work, and we work closely with other trades, architects, and project managers to ensure the plumbing is sequenced and delivered without causing delays to the wider programme.

Our New Build Plumbing Services

First Fix Plumbing

First fix is the foundation of your entire plumbing system, and it needs to be done right. This is the stage where supply pipes, waste pipes, soil stacks, and drainage runs are installed within the structure of the building — before walls are plastered, floors are laid, and ceilings are closed. Getting the positioning, sizing, and gradients right at this stage avoids costly alterations later.

Our engineers work from architect drawings or their own site surveys, coordinating with the building team to ensure pipes are routed efficiently, supported correctly, and positioned precisely where second fix connections will be needed. We flag any design conflicts early — before they become expensive problems.

This stage also includes notifying the relevant authorities where required under the Water Supply (Water Fittings) Regulations 1999, and ensuring that drainage work complies with Part H of the Building Regulations.

Second Fix Plumbing

Second fix is where your new build starts to feel like a real home. Once decorating is complete and surfaces are finished, our engineers return to connect and commission all the visible plumbing fixtures — sinks, baths, showers, toilets, taps, radiators, and hot water and heating systems.

Second fix requires careful workmanship to achieve a clean, professional finish. Connections need to be leak-free and properly supported, fixtures need to be set level and secure, and everything needs to be commissioned and tested before the property is signed off. We take as much care at this stage as we do during the structural work — because it’s what the end user actually sees and uses every day.

For bathroom fitting within a new build, our team can work from a full bathroom specification or advise on the best layout and fixtures for the space.

Hot Water System Design and Installation

Every new build needs a hot water system that’s properly designed for its size and usage pattern. Too small and residents will face constantly running out of hot water; too large and you’re wasting energy and money. We help our clients choose the right system — whether that’s an unvented cylinder, a combi boiler, a vented cylinder, or a thermal store — and install it to the relevant British Standards and Building Regulations.

For larger new builds or developments, hot water demand calculations are a critical part of the design process. Our water heater installation service covers all system types, and we can work with your M&E consultant or architect to specify the right solution for the project.

Drainage and Soil Stack Installation

Drainage in a new build needs to be right from the outset. Incorrect pipe gradients, poorly supported pipework, or inadequate soil stack sizing can lead to blocked drains, foul smells, and long-term maintenance headaches that are difficult and expensive to address once a building is finished.

We install all drainage and waste pipework in compliance with Part H of the Building Regulations, ensuring correct falls, adequate access points, and proper connection to the mains sewer or private drainage system. Where a CCTV drain survey of the existing drainage on site is useful before new connections are made, we can arrange that as part of the project.

Testing, Commissioning, and Handover

A new plumbing system isn’t complete until it’s been properly tested and commissioned. We pressure-test all supply pipework to confirm there are no leaks, check drainage falls and flow rates, and commission the hot water and heating system to confirm it’s performing correctly before handover.

We provide documentation covering all testing and commissioning results — essential for building control sign-off, for the new occupant’s records, and for any warranty or insurance requirements.

Why Getting New Build Plumbing Right Is Non-Negotiable

In a new build, the plumbing system is installed once and then largely hidden within the structure of the building. Getting it right first time isn’t just preferable — it’s essential. Remedying a poorly designed or incorrectly installed plumbing system after the building is complete is invariably far more expensive and disruptive than doing the job properly in the first place.

There are also significant regulatory requirements to navigate. New build plumbing must comply with:

  • Part G of the Building Regulations — covering sanitation, hot water safety, and water efficiency
  • Part H of the Building Regulations — covering drainage and waste disposal
  • The Water Supply (Water Fittings) Regulations 1999 — covering materials and methods used in connections to the mains supply
  • Part L of the Building Regulations — covering energy efficiency, which has implications for hot water system design

For gas-connected systems, all work must be carried out by a Gas Safe registered engineer. All relevant Catalyst Home Services engineers hold the certifications required for the work they carry out. See our licences and certifications for the full picture.

A well-designed, correctly installed plumbing system also contributes meaningfully to the value of the finished property. For new build homes in London, where buyers and tenants are sophisticated and often conduct thorough surveys, the quality of the plumbing system is not something that goes unnoticed.

Who We Work With

Property developers working on residential or mixed-use schemes in London rely on us as a reliable plumbing subcontractor who delivers on programme, communicates clearly, and doesn’t create problems for the wider build team. We’re experienced in working as part of larger construction programmes and understand the importance of coordination and sequencing.

Self-builders and custom home builders get a personal service and an engineer who takes the time to explain the options and the implications of different choices. We understand that a self-build is often the most significant project of someone’s life, and we treat it accordingly.

Architects and project managers working on residential new builds or conversions in London can bring us in at the design stage to advise on plumbing layouts, system sizing, and compliance requirements — often preventing issues that would be costly to resolve later.

Landlords and investors developing buy-to-let properties or HMOs need plumbing systems that are robust, compliant, and easy to maintain. Our residential AMC service means we can also be your maintenance partner once the development is complete and tenants are in.

Commercial developers fitting out offices, restaurants, or retail premises require commercial-grade plumbing that can handle the demands of a working environment. Our commercial plumbing team has the experience to design and install systems that perform reliably under sustained commercial use, and our commercial AMC keeps those systems maintained going forward.

How Our New Build Plumbing Process Works

New build plumbing is a programme of works, not a single visit. Here’s how we manage the process.

Step 1 — Initial consultation. Call us on +44 7400 265421 or get in touch online. We’ll discuss the scope of your project, the timeline, and what you need from a plumbing contractor. If you have drawings, we’ll review them; if not, we can carry out a site visit to understand the project.

Step 2 — Design input and specification. Where the project is at an early enough stage, we provide input on plumbing layouts, system sizing, and specification. Getting this right before work begins prevents costly changes later. We’ll also identify any compliance requirements that need to be addressed.

Step 3 — Detailed quotation. We provide a clear, itemised quotation covering first fix, second fix, hot water system installation, drainage, and commissioning — broken down so you can see exactly what’s included at each stage.

Step 4 — First fix. We mobilise to site at the agreed time and carry out all structural plumbing work in coordination with the building team. We keep the site manager and project manager informed throughout and raise any issues promptly.

Step 5 — Second fix. Once the building is at the right stage, we return to connect and commission all fixtures and appliances, working neatly and to a high standard of finish.

Step 6 — Testing, commissioning, and handover. All systems are fully tested and commissioned. We provide documentation, walk through the systems with the relevant parties, and ensure everything is signed off correctly for building control and handover purposes.

Why Choose Catalyst Home Services for Your New Build?

Choosing the right plumbing contractor for a new build is one of the most important decisions on your project. Here’s why clients across London choose us.

We have genuine new build experience — our engineers understand construction programmes, working alongside other trades, and the regulatory requirements that govern new build plumbing. This isn’t domestic repair work scaled up; it’s a different discipline, and we’re equipped for it.

We’re properly qualified — all gas work is carried out by Gas Safe registered engineers, and all relevant Building Regulations notifications are handled as part of our service. See our licences and certifications for full details.

We communicate clearly — we know that delays in plumbing can hold up the entire build programme. We’re prompt, we keep you informed, and we raise issues before they become programme problems.

Our pricing is transparent — staged quotations for each phase of the work, with no surprises at handover.

We think long-term — the plumbing system we install today is one we’d be happy to maintain and service going forward. Our AMC pricing and packages mean we can be your maintenance partner after completion too.

Read what our clients say on our reviews and testimonials page, and find out more about our approach on our Why Choose Us page.

Related Services

New build plumbing often connects with other services we provide. Here are the most relevant ones for new build and development projects.

Frequently Asked Questions

What is first fix plumbing in a new build?

First fix plumbing refers to all the pipework and drainage that is installed within the fabric of the building before plastering and finishing takes place. This includes supply pipes, waste pipes, soil stacks, and drainage runs — essentially all the plumbing that will be hidden within walls, floors, and ceilings once the building is complete. It’s the most critical stage of the plumbing programme because errors are difficult and expensive to correct once the building is closed up.

What is second fix plumbing?

Second fix plumbing is the stage that follows decoration and finishing. It involves connecting and commissioning all the visible plumbing fixtures — sinks, baths, showers, toilets, taps, and the hot water and heating system. Second fix requires a high standard of workmanship because it’s what the end user sees and uses every day. It also involves the final testing and commissioning of the entire plumbing system.

Do I need building regulations approval for new build plumbing?

Yes. New build plumbing must comply with several parts of the Building Regulations, including Part G (sanitation and hot water), Part H (drainage), and Part L (energy efficiency). Some work also needs to be notified to the local water authority under the Water Supply (Water Fittings) Regulations 1999. All of this is managed by Catalyst Home Services as part of our new build plumbing service — you don’t need to navigate the regulatory requirements yourself.

How early should I bring in a plumber on a new build project?

As early as possible — ideally at the design stage. Involving a plumber during the design phase allows pipework routes, system sizing, and compliance requirements to be factored into the building design rather than retrofitted into it. It also gives your plumber the opportunity to raise any issues before they become programme problems. If you already have drawings, contact us to discuss the project before work starts on site.

How long does new build plumbing take?

This depends entirely on the size and complexity of the project. A single residential new build typically involves two or three visits — first fix, second fix, and commissioning — spread across the build programme. Larger developments are managed as an ongoing programme of works. We’ll provide a clear programme at the quotation stage so you know exactly what to expect and when.

Can you work alongside other trades on site?

Yes, and we’re experienced in doing so. New build plumbing requires close coordination with builders, electricians, heating engineers, and tilers. We understand construction site protocols, work within the site manager’s programme, and communicate proactively about access requirements and sequencing. We don’t create problems for the rest of your build team.

What documentation do you provide on completion?

On completion of a new build plumbing package, we provide pressure test certificates for supply pipework, commissioning records for the hot water and heating system, and any notifications or completion certificates required by building control or the water authority. This documentation is important for your building control sign-off, for the new occupant’s records, and for any sale or letting of the property.

Do you cover new build plumbing across London?

Yes. We work on new build and development projects across a wide range of London postcodes. Check our service areas page to confirm we cover your location, or call us to discuss your project directly.

Ready to Discuss Your New Build Plumbing in London?

A new build is a significant undertaking, and the plumbing system at its heart deserves to be done by people who know exactly what they’re doing. Catalyst Home Services brings the experience, qualifications, and professionalism to deliver new build plumbing that is compliant, well-built, and designed to last.

Call us on +44 7400 265421, submit your enquiry online, or check our service areas page to confirm we cover your site. We’re also happy for you to read what our clients say about us before making a decision.