Reverse Osmosis System in Putney

⭐ Introduction

A reverse osmosis (RO) system is a water filtration device that removes impurities and contaminants from your tap water to deliver cleaner, better-tasting drinking water. It’s especially useful if you live in an area with hard water or notice unpleasant tastes or smells from your tap. RO systems are often installed under your kitchen sink and can be a healthier, more environmentally friendly alternative to bottled water.

Homeowners typically choose to get an RO system installed when they want improved water quality for drinking and cooking, when other filters haven’t worked well enough, or if they want to reduce minerals and chemicals such as chlorine, lead, or pesticides.

🔧 What the job involves

Installing a reverse osmosis system involves connecting the filtration unit to your cold-water supply and installing a dedicated tap for filtered water at your sink. The system uses a fine semipermeable membrane that filters out dissolved solids and impurities, sending clean water to the tap and flushing the rest away as wastewater down your drain.

The plumber will:

• Assess your existing plumbing and water pressure.
• Connect the system’s pre-filters, membrane, and post-filters as required.
• Fit a new tap (often a small, separate one beside your kitchen sink tap).
• Install a small pressurised storage tank if your system includes one.
• Connect the waste line to your sink’s drainage.
• Test the system for leaks and proper function.
• Explain how to change the filters and maintain the system.

RO systems also require proper disposal of wastewater, so the plumber ensures this meets UK plumbing regulations.

📝 Step-by-step from booking to completion

1. Initial enquiry: Contact a reputable plumber who has experience with water filtration installations. Discuss your water needs and system preferences.

2. Survey and quote: The plumber visits your home to check your plumbing setup, water pressure, space under the sink, and suitability for an RO system. They provide a written quote including parts, labour and any extras.

3. Scheduling the installation: Agree a date and time for the installation works. Confirm what preparations you may need to make (e.g. clearing under-sink cupboards).

4. Day of works: The plumber arrives, fits the system and dedicates tap, connects to your water supply and drain, tests it thoroughly, and explains operation.

5. Aftercare briefing: The plumber will outline filter replacement schedules, cleaning advice, and any warranty information.

6. Final paperwork: You receive any Fitting Certificate or guarantee documents applicable, plus a clear invoice.

💷 Main costs to expect

• Labour: Usually £100–£200 depending on installer and complexity.
• Materials/parts:
  • Basic RO unit: £150–£300
  • Dedicated tap: £40–£100
  • Storage tank (if needed): £50–£100
  • Filters & membranes (initial set): £50–£100
• Extras: Additional plumbing work (pipe rerouting, new valves) £50–£150
• Disposal: Minimal, may be included in labour
• Certification: Generally no formal certification needed but some companies provide a workmanship guarantee or installation report.

📊 What affects the price

• Plumbing accessibility (tight cupboard space or awkward pipework)
• Quality and size of RO system chosen (basic vs premium)
• Requirement for additional filtration stages (e.g. UV sterilisation)
• Presence of water softener or filters needing integration
• Extra installation steps (e.g. drilling new tap hole in sink)
• Regional labour rates and travel time
• Urgency or timescale for completion
• Any remedial work on existing plumbing or water pressure adjustments

⏱ How long does it take?

A straightforward installation typically takes between 2 to 4 hours. This includes removing any old fixtures, fitting the new system, and testing it.

More complex jobs—such as those requiring:

• multiple filtration stages,
• new pipework,
• integration with other water treatment devices,

can take up to a full day (6–8 hours).

🏠 Can you DIY it?

While some handy homeowners may manage to install simple under-sink filters, reverse osmosis systems are more complex because they:

• require connecting to cold water supply and waste pipes safely
• might need precise adjustments to water pressure
• involve drilling new tap holes if none exist

Improper installation can cause leaks, poor filtration, or water damage. There are no legal requirements like Gas Safe or Part P that apply directly to water filtration plumbing, but using a professional ensures compliance with good plumbing standards and local Building Regulations.

For peace of mind and to protect your home, hiring a qualified plumber experienced in RO systems is usually the best route.

💰 Typical UK price range

Expect to pay roughly between £300 and £600 for a complete reverse osmosis system installation, including parts and labour. This estimate includes VAT at the standard 20%.

Prices can vary depending on the factors above, but this range gives a reasonable expectation for most UK homes.

✅ Handy tips before you start

• Clear out the cupboard under the sink to give installers easy access.
• Check if your water pressure is within the recommended range (usually 2.5–6 bar).
• Ask the installer about filter replacement schedules—typical filters last 6–12 months.
• Register your system warranty and keep all paperwork safe.
• Plan for occasional servicing to maintain water quality and system longevity.
• Consider water quality testing before installation to target specific contaminants.
• If you’re renting, get permission from your landlord before installation.
• Keep the plumber’s contact details handy for future maintenance or issues.

Having clean, refreshing drinking water from your own tap is convenient and often cost-effective over time, especially if you drink a lot of bottled water now. Choosing a professional installation ensures the system works properly and protects your home.