bathroom fitting

Understanding the nuances of first-fix and second-fix plumbing is crucial for anyone embarking on a plumbing project or planning to call MML Plumbing for a project. But what exactly sets these two stages apart? Let’s delve into the details.

Key Takeaways:

  • The first fix lays the groundwork for the entire plumbing before surfaces like walls and floors are finished, while the second fix involves fitting visible components.
  • The first fix includes planning and installing pipework, waste water drainage, heating systems, and essential fixtures.
  • Coordination with other trades, thorough testing, and adherence to building regulations are essential.
  • Costs and duration of first-fix plumbing vary depending on the project’s scope and complexity.
  • Hiring a professional company like ours ensures that the work is done correctly and to code, setting the stage for a successful second fix.

Learn more about hpw can you ad value to your home!

Get a Free Plumbing Quote Today in Minutes

Contact our plumbers in North London today for a complimentary plumbing estimate and take the first step toward resolving your plumbing needs. Don’t hesitate to reach out now to discover how we can assist you with top-notch plumbing services at competitive rates.


What’s the difference between the first fix and the second fix plumbing?

In essence, the first fix involves laying the groundwork for your system, focusing on installing pipes and essential fixtures before surfaces like walls and floors are finished.

In the first fix, we will fit the underground pipe work, waste pipe for the bathroom (and shower valves) and the kitchen. Then this is followed by installing the hot and cold water pipework for the kitchen and bathrooms, then the central heating flow and return for the radiators.

We will also fit the pipes for the boiler or hot water cylinder. 

The second fix, on the other hand, occurs after these surfaces’ internal walls and floor are complete and entails fitting the visible components such as taps, showers, and sinks.

In the second fix, we will install the boiler, hot water cylinder, toilet, sink, tap, and showers.

bathroom sanitaryware install

First fix plumbing

What are the stages?

Planning the pipework: at the heart of any successful project lies meticulous planning. We carefully strategize the layout of pipework, ensuring optimal functionality and efficiency. Factors such as water pressure, flow rates waste pipe used, and building regulations are taken into account to create a comprehensive plan that will guide all the work to follow.

For bigger projects, we also need to design the system with a heating system designer engineer.

Boilers and flues first fix

Central heating systems are a vital aspect of many home setups. MML plumbers install boilers and flues, positioning them strategically to keep hot water and provide efficient heating throughout the property. Attention to detail is paramount to guarantee safe and effective operation, especially when connecting the boiler to the house or existing system or installing a new one in a new build.

combi boiler installation

Wastewater installation

Effective bathroom wastewater management is essential for maintaining hygiene and sanitation standards. This stage involves installing drainage pipes and drainage systems to safely and efficiently remove wastewater from sinks, showers, toilets, and other bathroom fixtures. MML plumbers ensure that the waste pipes are properly connected and positioned to prevent backflow and facilitate easy access for maintenance and testing.

Installing Drainage Systems Along with the Water Supply Pipes

In addition to wastewater ground drainage systems, it includes the installation of water supply pipes. These pipes deliver clean, potable water to various fixtures throughout the property, such as taps and appliances. We use materials like push-fit pipes or solvent weld joints to ensure secure connections and prevent leaks. Attention to detail at this stage helps prevent issues such as leaks and pressure fluctuations, and all the work is done by building regulations.

Installing Heating Systems

In colder climates, heating systems play a vital role in maintaining comfort and warmth within a property. In this stage, we include the fitting of space heating systems, such as radiators or underfloor heating. Our heating engineer carefully fits pipes and connects radiators to the central heating system, ensuring proper insulation and preventing heat loss. For radiators and underfloor heating, they lay down the pipework or heating mats and connect them to the boiler or heat source on the second fix.

first fix installation by MML Plumbing

First-fix electrics

In addition to plumbing work, the first fix often involves coordinating with electricians to install electrical fixtures, appliances and wiring. MML PLumbings ensures that any pipework or fixtures do not interfere with the electrical installation and vice versa. This may include installing conduits for electrical wiring, fitting face plates for the light fixtures, switches and sockets, and positioning light fittings and fixtures.

Tightness Test

Once all the first-fix plumbing work is complete, plumbers conduct thorough testing to ensure that everything is functioning as it should. This may include pressure testing the pipework, checking for leaks in waste pipes, and verifying the proper operation of heating systems and appliances. Any issues are addressed immediately before proceeding to the second fix plumbing stage.

first fix installation by MML Plumbing

Mastering First Fix: Key Considerations and Best Practices for Success

  • Understanding the layout and requirements of your system during this stage is crucial for ensuring optimal functionality and efficiency.
  • Proper planning and coordination with other trades, such as electricians and contractors, help streamline the installation process and avoid costly delays.
  • Attention to detail in the positioning and connection of pipework, waste pipes, and fixtures prevents issues such as leaks, blockages, and backflow in the future.
  • Thorough testing of the system before proceeding to the second fix helps identify and address any issues early on, saving time and money down the line.
  • Incorporating energy-efficient solutions, such as underfloor heating and high-efficiency boilers, enhances comfort and reduces long-term energy costs.
  • Ensuring that all plumbing work is done in compliance with building regulations and standards is essential for safety and legal compliance.
  • Hiring experienced and reputable plumbers for the work not only ensures quality workmanship but also provides peace of mind knowing that your system is in capable hands.
  • Effective communication between homeowners and other stakeholders throughout this stage helps clarify expectations, address concerns, and ensure that the final work meets the homeowner’s needs and preferences.
  • Taking the time to plan the process and asking questions from the plumber or gas engineer can empower you as a homeowner to make informed decisions and actively participate in the project.
Reliable Engineers

Get Your Project Started Right

Ready to begin your plumbing project? Don’t leave anything to chance. Contact MML Plumbing’s experienced team today to ensure a smooth and successful first fix stage. Let us lay the groundwork for your system, setting the stage for ultimate comfort and functionality in your home. Reach out now to schedule your consultation!

Learn more about boiler installation steps and process!

Frequently Asked Questions