Drainage & Sewer Pipe Materials
uPVC, ABS, Cast Iron & Clay Compared (2026)

What a drainage system does

A home's drainage is a drain-waste-vent system: pipes from each sink, shower, floor trap and toilet join a soil stack or underground drain that runs to the public sewer or a septic tank. Each fixture has a water-filled trap that keeps sewer gas out, and vent pipes let air in so the water flows freely and the traps are not sucked dry. Unlike the pressurised water supply, drains rely on gravity, so a steady downward fall along every pipe is essential. Supply pipes are a different subject, covered in our water pipe material guide.

Drainage pipe materials compared

uPVC: the everyday choice

uPVC (unplasticised PVC) has the longest track record of the plastic pipes, and Wikipedia's plastic pipework article notes it is the pipe most often used for sanitary sewers and is allowed for waste lines in homes. It is light, easy to cut and join with solvent cement, and does not rust. It is not suited to hot water supply, and exposed runs should be clipped at close intervals and protected from direct sun and knocks. In drainage, the details that matter are the right fittings (long, smooth bends rather than sharp corners), access points for rodding, and a consistent fall.

ABS pipe

ABS (acrylonitrile butadiene styrene) is a rigid, impact-resistant plastic that the same article lists as most commonly used for drain-waste-vent applications and non-pressure soil and waste piping. In Malaysia it appears less often than uPVC but shows up in some fittings and imported systems. ABS and uPVC use different solvent cements, so a joint between the two needs a proper transition fitting rather than whatever glue is to hand.

Cast iron soil stacks in older buildings

Cast iron was the traditional material for soil stacks and drains. It is heavy and quiet, but it corrodes: Wikipedia's cast iron pipe article describes corrosion on both inner and outer surfaces, and notes that in sewer systems acidic gases produced by microbes attack the inside of the pipe. ClickBina's old-house waterproofing guide describes original galvanised and cast-iron pipework corroding from the inside in older homes. Signs of a failing cast iron stack are rust streaks, damp around joints, a smell near the stack, and slow drains on the lower floors.

In a condo or flat, the main soil stack is usually common property, so repairs are arranged through the JMB or MC, not by the owner alone.

Vitrified clay under older houses

Vitrified clay pipe is a hard, inert ceramic that has been used for sewers for a very long time. The Wikipedia article credits it with long life and resistance to almost all domestic sewage, but notes it is heavier than plastic, has more joints over a given length and is more brittle, which can lead to cracking and leaks. In older Klang Valley houses, clay lines under the yard are where tree roots and settling ground break joints, giving repeated blockages and smells.

Fall, vents and traps: what makes any drain work

• Fall: every drain needs a steady slope towards the sewer; flat or sagging runs collect grease and solids.
• Vents: a vented stack lets air in so water flows freely and traps are not siphoned dry, which is what lets sewer smells in.
• Traps: each fixture needs a trap that holds water; a dried-out floor trap in a spare bathroom is a common smell source.
• Access: rodding eyes and inspection chambers at bends and junctions make clearing a blockage quick.

Our drain smell guide covers the smell side, and the clogged drain guide covers blockages.

When to replace old drainage pipe

Repeated blockages in the same run, cracked or offset joints seen on a camera, root intrusion, corroded cast iron and leaks into a ceiling or slab are the usual reasons to replace a section. A drain camera inspection shows the condition before anything is hacked. During a renovation, while walls and floors are open, it is sensible to check the waste pipes and replace brittle or corroded sections at the same time; our re-piping cost guide makes the same point.

Drainage in a renovation: what to ask for

• Material and fittings named in the quote, with long-radius bends and access points.
• The fall checked along every new run before the floor is screeded.
• A water test of new drains before tiling and ceiling work.
• Joints between old and new pipes (for example cast iron to uPVC) made with proper adaptors.
• Management approval before touching a shared stack in a strata building.

What drain inspection and clearing cost

These are the published lines on ClickBina guides (market estimate 2026, Klang Valley). Pipe replacement is quoted after the line has been inspected.

A camera inspection before a repair usually saves money, because it shows whether a pipe needs clearing, a section replaced, or a full re-route.

How ClickBina can help

Drainage work is quoted case by case. WhatsApp us your job details for a quote: the symptom (blockage, smell, leak), where it is, the age of the house and whether it is landed or strata. ClickBina is an experienced KL & Selangor contractor that handles whole-house refurbishment and trade coordination. We reply within the hour, the price we agree is a flat price with no hidden charges, and a site visit is RM150, waived if you go ahead. Leak detection is a separate paid visit at RM300 – RM800.

Sources & methodology

• Wikipedia: Plastic pipework — uPVC and ABS uses in soil, waste and drain-waste-vent piping.
• Wikipedia: Vitrified clay pipe — long life, sewage resistance, weight, joints and brittleness.
• Wikipedia: Cast iron pipe — internal and external corrosion in sewer systems.
• Wikipedia: Drain-waste-vent system — traps, vents, soil stack and the need for fall.
• ClickBina old-house waterproofing, clogged drain, hydro-jetting, plumbing services and porch seepage guides — cast-iron corrosion and prices; convenience store fit-out guide — site visit wording.

How we estimated prices: every RM figure on this page is quoted unchanged from the ClickBina guides named above. They are indicative Klang Valley ranges for 2026, not fixed rates.