Service
Reverse Osmosis Drinking Water Systems & Installation
Reverse osmosis is a treatment process that pushes water through a semi-permeable membrane under pressure, separating out substances too large to pass through it. In homes, it's typically installed under the kitchen sink with a dedicated faucet, producing water for drinking and cooking.
Point of use, not whole house RO treats the water at one tap — not the water going to your shower, your laundry or your water heater. It complements whole-house treatment rather than replacing it.
The Mechanism
How the Process Works
Water arrives at the system under household pressure and passes first through pre-filtration — stages designed to capture sediment and reduce chlorine, both of which would otherwise shorten the life of the membrane.
It then reaches the membrane itself. Pressure forces water through an extremely fine semi-permeable material; substances too large to pass through are carried away to a drain line. The treated water collects in a small storage tank so there's a usable volume ready when you turn the tap on.
On the way out, it passes a post-filter for final polishing before reaching the dedicated faucet at your sink.
Because pre-filtration protects the membrane, the condition of your feed water has a direct effect on how long the membrane lasts. That's why hardness and sediment upstream are part of the conversation.
Be Clear About This
Two Things Worth Understanding Before You Buy
Both of these get glossed over regularly, and both change what you should expect from the system.
RO is point-of-use
- Installed at a single tap, usually the kitchen sink
- Produces a limited volume into a storage tank
- Does not soften water throughout the home — see water softeners
- Does not treat shower, laundry or appliance water
- Frequently installed downstream of other treatment
Performance is system-specific
- What a given system reduces depends on that specific unit
- Membrane type and stage configuration matter
- Feed-water conditions affect real-world results
- Reduction claims should come from the manufacturer's verified, current specifications
- We won't claim a system removes "everything" — no system does
If a company tells you their RO system removes everything, ask to see the manufacturer's documented performance data for that model. A legitimate answer exists for every real system; a vague one is a signal.
Installation
Where It Goes
The system lives inside the sink cabinet. The faucet mounts on the sink or countertop — sometimes in an existing hole from a soap dispenser or sprayer, sometimes in a new one we drill. A drain connection handles the water the membrane rejects, and the storage tank sits alongside the filter stages.
In a typical suburban kitchen this is straightforward. In a Philadelphia rowhome with a shallow cabinet or unusual plumbing, the practical question is often whether everything fits and still leaves the cabinet usable — which is something we look at rather than assume.
Running a line to a refrigerator or ice maker is a common addition. Whether it's practical depends on distance and routing.
Specification
What Determines the Right System
Your actual concern
Taste, a specific substance identified by testing, or general drinking-water quality — each points somewhere slightly different.
Feed-water conditions
Hardness and sediment shorten membrane life. Testing tells us whether pretreatment is worth it.
Household drinking demand
How much drinking and cooking water you actually use determines the output and tank size you need.
Under-sink space
Cabinet depth, plumbing position and disposal units all constrain what physically fits.
Faucet hole availability
An existing hole, or drilling a new one — and what your countertop material allows.
Water pressure
RO relies on pressure. Low incoming pressure affects output and may change the specification.
Drain connection
The reject line needs a proper connection, done to code.
Refrigerator tie-in
Worth deciding upfront — it affects routing and the output you need.
Verified specifications
Performance expectations come from the manufacturer's documented data for that model, not from a general claim about RO.
Living With It
What Ownership Involves
An RO system is low-effort but not no-effort.
- Pre- and post-filters. Changed on a schedule. These protect the membrane, so letting them go costs you the expensive part.
- The membrane. Replaced at a longer interval than the filters. How long depends heavily on feed-water conditions.
- Sanitisation. Done at service, particularly when the system has been opened up.
- Watch for changes. Reduced flow at the faucet or a change in taste usually means a filter or the membrane is due.
We'll tell you the intervals for your specific system at installation, and we stay available to handle them. More in our guide to maintenance intervals.
Related Reading
FAQ
Reverse Osmosis Questions
No. Residential RO is point-of-use treatment, typically under the kitchen sink with its own faucet. It produces water for drinking and cooking. It doesn't soften your home's water and doesn't treat the water going to your shower, laundry or water heater.
What a given system reduces depends on that specific unit, its membrane, its stage configuration, the condition of the feed water and the manufacturer's verified performance specifications. No RO system removes everything, and any claim that one does should be treated with caution.
RO systems send some water to the drain as part of the separation process. How much depends on the system design, feed pressure and water conditions. It's a genuine trade-off, and we'll explain what to expect for the system we're recommending rather than skip past it.
They do different jobs. RO treats drinking water at one tap; a softener addresses hardness throughout the home. Hardness and sediment also shorten membrane life, so where hardness is high, softening ahead of the RO often protects it and extends its working life.
Often yes, depending on the distance, the routing and the system's output. It's a common request, and it's something we assess during the consultation rather than assume.
Drinking water systems across Greater PhiladelphiaInstalled to fit the space you actually have.
Next Step
Better Drinking Water at the Kitchen Tap.
Tell us what's bothering you about the water you drink. We'll work out whether RO is the answer, and whether anything needs to happen upstream of it first.