Cold water distribution

What a cold-water distribution covers

Cold water enters the apartment through the riser from the building main. Right at the entry there is an apartment shut-off (sometimes several — a main one and an extra for garden/balcony use), a meter, and then distribution to the fixtures:

• Toilet — cistern (and a hygiene shower, if present).
• Basins — bathroom, kitchen.
• Bathtub/shower — mixer.
• Cold feed to the boiler — this is also the "supply" for the entire DHW system.
• Washing machine and dishwasher — usually cold only.
• Balcony/yard — a tap for watering or hose-down (if present).
• Filters — mechanical at the inlet, sometimes a softener for hard water.

Distribution layouts

Tee

A trunk line runs across the apartment with tees branching to each fixture. The most common layout for small apartments. Quick to install, inexpensive.

• Pressure drops when two points are used at once.
• Repairing one point requires shutting down the whole line.

Manifold

From the apartment inlet, a trunk leads to a distribution manifold, and from it a dedicated pipe runs to each fixture. More expensive, but more convenient in use.

• Stable pressure at every point.
• Individual isolation valves on each outlet.
• Any point can be serviced without shutting off the others.

Hybrid

Manifold for "complex" points (shower, kitchen, boiler), tees for "simple" ones (toilet, washer). A cost/convenience compromise.

Materials

PEX (cross-linked polyethylene)

The primary material in new builds. Blue for cold water. Flexible, installed in screed or along walls without welding.

• Service life 50+ years.
• Handles up to 16 bar.
• Doesn't corrode, doesn't scale from the inside.

Multilayer (PEX-AL-PEX)

A PEX alternative with similar specs. Threaded joints need occasional retightening.

Copper

Reliable, long-lasting, expensive. More common in high-end builds or where high heat resistance is needed (less relevant for cold water).

Polypropylene (PP-R)

Rigid lengths joined by heat fusion. A cheaper alternative, but less flexible than PEX.

Galvanized steel

Found in older apartments. Over 30–40 years it scales up from hard-water salts and pressure drops. Replaced during renovation.

Inlet assembly — what goes in at the apartment entry

1. Ball shut-off valve — the main one, for killing the whole apartment.
2. Coarse filter — mesh strainer, catches sand and scale from the riser. Mandatory for protecting mixers and appliances.
3. Water meter — some management companies install it before the apartment, others inside.
4. Pressure reducer — if inlet pressure is above 4 bar (typical for Israel). Protects mixers and appliances.
5. Fine filter — optional, before a softener or a drinking-water point.
6. Water softener — optional, but recommended in Israel given hardness of 250–400 ppm.

What the plumber does during distribution

1. Plan the routes and draw-off points.
2. Chase walls or lay in screed (screed is more common).
3. Install the inlet assembly and manifold (for manifold layouts).
4. Run the pipes from the manifold/trunk to each point.
5. Fit isolation valves at each point (to allow mixer swaps without killing everything).
6. Pressure test the system at 10 bar for 24 hours — a mandatory step before sealing up.
7. Final fixture connection.

Pricing in Israel

• Cold-water distribution in a 2-room apartment (tee, PEX) — 2,000–4,000 ILS
• Manifold distribution in a 3–4 room apartment — 4,500–8,000 ILS
• Replacing galvanized with PEX (incl. demolition) — 3,000–6,000 ILS
• Turnkey inlet assembly (valve + filter + meter + reducer) — 700–1,500 ILS labor + 600–1,400 ILS parts
• New cold-water point (for a washer/dishwasher) — 400–900 ILS
• Water softener — 2,500–7,000 ILS equipment + 500–1,000 ILS installation

Cold water is usually cheaper than hot — no insulation, slightly fewer materials (blue PEX is cheaper than red).

Common mistakes

• No inlet filter. Sand and scale from the riser reach mixer cartridges — they clog in 1–2 years and the mixer drips.
• No isolation valves at fixtures. To swap a mixer you shut down the whole apartment — annoying.
• Joints buried in screed. Any leak = floor demolition. Joints must sit behind inspection hatches.
• Same color for cold and hot pipes. Five years later, nobody remembers what's what. Use blue for cold, red for hot — that's the standard.
• Ignoring pressure. Inlet is 5–6 bar, the mixer is rated for 3 bar — seals weep and lifespan drops.

Timeline

• Full distribution in a 3-room apartment — 3–4 working days (incl. chasing).
• Replacing old distribution with PEX while keeping points — 1–2 days.
• Connecting a new cold-water point — 1–3 hours.
• Installing the inlet assembly — 2–4 hours.