What is the difference between first fix and second fix plumbing?

First fix is the pipework installed before walls are plastered and floors are laid. Second fix is fitting and connecting the visible items afterwards, such as basins, toilets, taps, showers and radiators.

Do you install bathrooms from start to finish?

Yes. We handle strip-out, plumbing, electrics, tiling, fitting and making good, so a bathroom is delivered by one contractor rather than several separate trades.

Can you fit a new boiler?

Boiler installation and any work on gas appliances is carried out only by Gas Safe registered engineers, with the installation notified and certificates issued.

Build & Refurbish

Plumbing works

Clean, pressure-tested installations with neat pipe runs you would be happy to leave exposed. From a single leak to a whole-house first fix.

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Plumber cutting new copper pipework beneath a bathroom vanity

In short

What plumbing work does MJ Site Solution carry out?

MJ Site Solution carries out domestic and light commercial plumbing across London and the South East: first and second fix, bathroom and kitchen installations, radiators and heating circuits, leak repairs and pressure testing. Installations meet the Water Supply (Water Fittings) Regulations, and gas work is completed by Gas Safe registered engineers.

Last reviewed 21 September 2026

Scope: First fix, second fix, bathrooms, kitchens, heating
Regulations: Water Supply (Water Fittings) Regulations 1999
Gas work: Gas Safe registered engineers only
Testing: Pressure tested and commissioned

Scope

What is included.

First and second fix plumbing
Bathroom and wet-room installations
Kitchen plumbing and appliance connection
Radiators, heating circuits and controls
Leak detection and repairs
Pressure testing and commissioning

First and second fix plumbingBathroom and wet-room installationsKitchen plumbing and appliance connectionRadiators, heating circuits and controlsLeak detection and repairsPressure testing and commissioning

Delivery

How we deliver it.

New navy shaker kitchen beneath a rooflight in a renovated period home

Step 01 / 03

Assess

Existing services surveyed and isolation points confirmed before anything is cut.

33%

Step 02 / 03

Install

Copper and multilayer pipework run neatly, clipped and labelled.

67%

Refurbished Victorian ground floor opened into a new navy kitchen, with oak flooring and restored cornicing

Step 03 / 03

Test

Pressure tested, flushed and commissioned, with results recorded.

100%

Standards & compliance

Installations to Water Supply (Water Fittings) Regulations 1999. Gas and boiler work only by Gas Safe registered engineers.

Questions

Plumbing works: common questions.

First fix is the pipework installed before walls are plastered and floors are laid. Second fix is fitting and connecting the visible items afterwards, such as basins, toilets, taps, showers and radiators.
Yes. We handle strip-out, plumbing, electrics, tiling, fitting and making good, so a bathroom is delivered by one contractor rather than several separate trades.
Boiler installation and any work on gas appliances is carried out only by Gas Safe registered engineers, with the installation notified and certificates issued.

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