Dadex Pipes & Fittings — Nikasi uPVC Systems
Pakistan’s most trusted soil, waste and vent piping system. Arfa Trading supplies genuine Dadex Nikasi uPVC pipes and fittings for residential, commercial, and industrial construction across Pakistan.
What is Dadex Nikasi?
Dadex Nikasi Pipes and Fittings are an unplasticized PVC (uPVC) building pipe system manufactured by Dadex Eternit Limited — Pakistan’s oldest and most established pipe systems manufacturer, incorporated in 1959. Nikasi is specifically engineered as a Soil, Waste and Vent (SWV) system, designed to carry solids present in both foul and surface water effluents with minimum risk of blockade. The system is available in six diameters — 40 mm, 50 mm, 75 mm, 110 mm, 160 mm and 200 mm — in standard pipe lengths of 3 meters and 4 meters, with a comprehensive fittings range in both solvent cement and rubber ring joint types. All Nikasi pipes and fittings conform to international standard ISO 3633:2002(E) / EN 1329:1999 and Pakistan Standard PS 3214:1992. Arfa Trading is your authorized Karachi-based supplier for the complete Dadex Nikasi range, with competitive pricing and delivery across Pakistan.
Who is Dadex Eternit Limited — and why does it matter?
When a builder in Karachi specifies a drainage system, the name they reach for most often is Dadex. That trust was not built overnight. Dadex Eternit Limited was incorporated as a public limited company in Pakistan on 13 April 1959 — making it one of the country’s oldest continuously operating building materials manufacturers. Founded by Mr. Kassim Dada, the company started producing fiber cement roofing systems in Hyderabad before expanding into pipe systems in Karachi in 1966.
The company today operates manufacturing facilities in Hyderabad and Lahore, maintains sales offices in Karachi, Lahore, Multan, Faisalabad, Islamabad and beyond, and holds a wide dealer and distributor network across Pakistan. It is listed on the Pakistan Stock Exchange (PSX) under ticker DADX, which means its financial records, quality standards and governance are publicly audited and transparent — a significant trust indicator for builders and procurement managers.
Dadex’s principal business is the manufacture and sale of construction materials, which primarily includes thermoplastic pipe systems (uPVC, PPR, HDPE), chrysotile cement pipe systems, roofing products, and architectural cladding systems. The company also merchandises imported pipe fittings and accessories. Its products serve construction, housing, architecture, telecommunications and infrastructure segments — for public, private, industrial and commercial clients, as well as export markets.
In terms of certifications and quality recognition, Dadex holds ISO 9001 (Quality Management), ISO 14001 (Environmental Management) and ISO 45001 (Occupational Health & Safety) certifications. Its products carry accreditation from the Pakistan Standards and Quality Control Authority (PSQCA). The company also received certification from the American Petroleum Institute (API) to use its official monogram on PE gas pipes, and was recognized as an Investor in People (IIP) company. Dadex has also acquired the Chamber Trust Seal — a testament to its ethical business practices.
Critically for building contractors, Dadex entered into a technical know-how agreement with Wavin Overseas B.V. of the Netherlands for the production of thermoplastic pipe systems. This Dutch collaboration underpins the engineering rigour behind the Nikasi system — Wavin is one of the world’s foremost plastic pipe manufacturers, and that partnership brought global production standards to Pakistani manufacturing.
Dadex Nikasi uPVC Pipes & Fittings — a complete system
The word Nikasi — drawn from Urdu — means drainage or outflow, and it is an apt name for Pakistan’s most widely used building drainage pipe system. Dadex Nikasi is a complete unplasticized polyvinyl chloride (uPVC) soil, waste and vent (SWV) building pipe system, engineered specifically to carry both the liquid and solid matter present in domestic and commercial waste water and sewage, with minimum risk of pipe blockage.
What sets Nikasi apart from generic uPVC drainage products is that it is a system — not just a pipe. Dadex supplies a fully coordinated range of pipes and fittings in matched sizes and specifications, manufactured to the same standard, using the same material formulation and quality process. This means every joint, bend, trap and tee you install alongside a Nikasi pipe has been designed to work with it — ensuring consistent hydraulic performance, chemical compatibility and long-term durability across the entire drainage network of a building.
The material — unplasticized PVC — is fundamentally different from plasticized PVC (flexible PVC used in cables or hoses). Unplasticized PVC is rigid, dimensionally stable, extremely smooth on the interior bore, and resistant to a broad range of chemicals encountered in domestic and industrial wastewater. It does not soften at normal soil and waste water temperatures, and it does not react with the acids, alkalis or biological matter present in sewage.
Material properties and technical advantages
Low Flow Loss
The smooth uPVC bore offers very low hydraulic resistance. Waste water and solids flow freely with minimal friction loss, reducing the risk of blockade in drainage stacks and horizontal runs.
Non-Corrosiveness and Chemical Resistance
uPVC does not corrode, rust or oxidise. It resists a wide range of household and industrial chemicals — including bleach, detergents, organic acids and dilute alkalis — without degradation over the service life of the building.
Lightweight and Easy to Handle
Nikasi pipes are significantly lighter than cast iron, galvanised steel or concrete drainage pipes. This reduces handling labour, simplifies installation in high-rise buildings, and lowers transport costs across Pakistan.
Self-Extinguishing
The uPVC formulation used in Nikasi is self-extinguishing — it will not sustain a flame once the ignition source is removed. This is a critical fire safety property for internal drainage stacks in residential and commercial buildings.
Non-Conductivity of Electricity
uPVC is an electrical insulator. Unlike metallic pipe systems, Nikasi pipes do not create earth fault paths or require electrical bonding — simplifying compliance with building electrical regulations.
Resistant to Organic Growth
Dadex Nikasi is resistant to the growth of algae, bacteria and fungi on its pipe walls. The smooth bore and anti-microbial surface properties maintain drainage performance and hygiene over decades of service.
Important for specifiers: Nikasi’s grey colour is a standard identifying feature of this SWV system. It visually distinguishes drainage pipes from Dadex Ecoplast (white, for cold potable water supply) and from Dadex Polydex PPR (green, for hot and cold pressure water). Always verify colour coding on site to prevent system cross-connection.
Nikasi pipes — sizes, lengths and specifications
Dadex Nikasi pipes are available in six nominals outside diameter sizes, covering fixture waste connections from washbasins right through to main building drains. Both 3-metre and 4-metre standard lengths are available in most sizes.
| Nominal OD | Primary Application | Std Lengths | Joint Type | Standard Conforms To |
|---|---|---|---|---|
| 40 mm | Washbasin, bath, shower waste connections | 3 m / 4 m | Solvent cement | ISO 3633 / EN 1329 / PS 3214 |
| 50 mm | Kitchen sink, floor trap and gully waste | 3 m / 4 m | Solvent cement | ISO 3633 / EN 1329 / PS 3214 |
| 75 mm | Branch drain, vent stack, bath waste collector | 3 m / 4 m | Solvent / Rubber ring | ISO 3633 / EN 1329 / PS 3214 |
| 110 mm | WC soil connection, main soil and vent stack | 3 m / 4 m | Solvent / Rubber ring | ISO 3633 / EN 1329 / PS 3214 |
| 160 mm | Horizontal drain collector, building sewer connection | 3 m / 4 m | Rubber ring | ISO 3633 / EN 1329 / PS 3214 |
| 200 mm | Main building drain, large commercial drainage | 3 m / 4 m | Rubber ring | ISO 3633 / EN 1329 / PS 3214 |
Nikasi fittings — a comprehensive range
The strength of the Nikasi system lies in its fittings range. Every drainage layout — no matter how complex — can be built using Dadex Nikasi fittings without resorting to site-fabricated connections or incompatible components from other manufacturers. Arfa Trading stocks the complete Dadex Nikasi fittings portfolio.
- P-Traps (solvent cement and rubber ring)
- Multi-traps for combined fixture connections
- Bottle traps (40 mm and 50 mm)
- Floor trap / gully trap units
- 90° bends (short and long radius)
- 45° bends (short and long radius)
- Equal tee branches
- Unequal (reducing) tee branches
- Access pipes with screw-on access cap
- Sockets and couplings (plain)
- Expansion (slip) sockets
- Reducers (concentric and eccentric)
- End caps and pipe stoppers
- Vent cowls and roof flanges
- Boss pipe adaptors (in-situ branch connection)
- Collar / pipe clips and brackets
Fittings are available in both solvent cement joint and rubber ring push-fit joint configurations. Solvent cement fittings (conforming to BS 4346 Part 3 for the adhesive) are typically used for smaller diameter connections (40 mm–75 mm) and locations where a permanent, rigid joint is required. Rubber ring fittings are preferred for larger diameters (75 mm and above) and for horizontal runs where thermal expansion must be accommodated.
International standards compliance — every Nikasi product is certified
Dadex Nikasi pipes and fittings are manufactured and independently tested against internationally recognized standards. Pipes conform to ISO 3633:2002(E) / EN 1329:1999 and PS 3214:1992. Fittings with solvent cement joints and fittings with rubber ring joints both conform to ISO 3633:2002(E) / EN 1329:1999. The solvent cement itself conforms to BS 4346 Part 3. Dadex Eternit as a company holds ISO 9001, ISO 14001 and ISO 45001 management system certifications, and all products carry PSQCA accreditation.
Where Dadex Nikasi pipes are specified and used
Dadex Nikasi is Pakistan’s most widely specified uPVC drainage system precisely because it covers every drainage requirement in a single, standards-compliant system. From the smallest washbasin waste in a domestic bathroom to the main building drain of a 30-storey commercial tower, the Nikasi range provides the correct pipe diameter, fitting type and joint system for every situation.
- Residential houses, bungalows and townhouses (internal SWV stacks)
- Multi-storey apartment buildings (vertical soil and waste stacks)
- Commercial offices, retail centres and shopping malls
- Hotels, serviced apartments and hospitality developments
- Hospitals, clinics, laboratories and healthcare facilities
- Schools, colleges, universities and educational campuses
- Industrial factories, warehouses and manufacturing plants
- Government buildings, public infrastructure and housing schemes
- Rainwater downpipes and surface water collection systems
- Building sewer connections to municipal drainage mains
- Plumbing retrofits and renovation projects on existing buildings
- High-rise construction in DHA, Bahria Town and other schemes
Nikasi is equally at home in single-pipe systems — where one stack serves both soil and waste — and in two-pipe systems, where separate stacks handle soil from WC connections and waste from basins, sinks and baths. The full fittings range supports both configurations without any hybrid products required.
For rainwater applications, Nikasi’s grey uPVC is UV-stabilized, making it suitable for exposed external downpipes in Pakistan’s sun-intense climate. Sizes 75 mm and 110 mm are the most commonly specified for residential rainwater downpipes, while 160 mm and 200 mm pipes are used for large-area roof drainage collectors and surface water gullies.
Understanding the complete Dadex pipe system portfolio
Arfa Trading specializes in the Dadex Nikasi drainage system, and our team can also advise on other Dadex pipe systems for different applications within the same project. Understanding where Nikasi sits within the full Dadex portfolio helps ensure the right product is specified for every stage of your building’s plumbing and drainage design.
| Dadex Brand | Material | Colour | Primary Use | Key Standard |
|---|---|---|---|---|
| Nikasi | uPVC | Grey | Soil, waste, vent and rainwater drainage | ISO 3633 / EN 1329 |
| Ecoplast | uPVC | White | Cold potable water supply and distribution | ISO 1452 / BS EN 1452 |
| Flowline | uPVC | Orange/Grey | Underground sewer pipe system (push-fit) | EN 1401 |
| Polydex | PPR (Polypropylene Random) | Green | Hot and cold water supply; air conditioning | DIN 8077/8078 |
| T-Flex | HDPE/PE | Black (blue stripe for water) | Water supply, gas distribution, cable ducts | ISO 4427 / EN 12201 |
| CC Pipes | Chrysotile Cement | Grey | Water distribution, sewer, agriculture | ISO 160 |
Never mix drainage and pressure systems. Nikasi (grey uPVC) is a drainage pipe rated for gravity flow only. Do not use it for pressurised water supply applications. Conversely, Ecoplast white uPVC water supply pipes are pressure-rated and not suitable for carrying foul water or sewage. Using the wrong pipe system for an application voids all standards certifications and creates a safety hazard.
Installing Dadex Nikasi — jointing methods explained
Solvent cement joints
Solvent cement jointing is the standard method for Nikasi pipes up to 75 mm diameter, and is also used on larger sizes where a permanently rigid connection is specified. The solvent cement — conforming to BS 4346 Part 3 — chemically welds the pipe and fitting together by partially dissolving the uPVC surfaces, creating a molecular bond as the solvent evaporates. When correctly made, a solvent cement joint is stronger than the pipe wall itself.
The process requires:
- Cutting the pipe square and removing burrs from the cut end.
- Dry-fitting to confirm alignment before cementing.
- Applying solvent cement evenly to both the pipe spigot end and the fitting socket, using the correct brush size.
- Pushing the pipe firmly into the socket with a quarter-turn twist to distribute the cement.
- Holding the joint firmly for 20–30 seconds.
- Allowing a minimum 15–30 minutes before disturbing, and 24 hours before flow or pressure testing. Work in ventilated conditions — solvent cement vapor is flammable and should not be inhaled.
Rubber ring push-fit joints
Rubber ring (elastomeric ring) joints are standard for Nikasi fittings in 75 mm diameter and above, and are preferred for long horizontal drain runs in all sizes. The rubber ring seal is factory-fitted inside the fitting socket. Installation requires only lubricating the pipe spigot end and pushing it firmly home into the socket until it reaches the internal stop.
The rubber ring joint is not permanently rigid — it permits a small degree of angular deflection and longitudinal movement. This is an important advantage in horizontal buried drains and building slabs were ground movement, thermal expansion or building settlement could otherwise stress rigid joints to failure. Rubber ring joints also make future maintenance easier, as individual pipe sections can be removed and replaced without solvent cement cutting.
Support and fixing
Nikasi pipes should be supported at regular intervals using Dadex pipe clips or approved equivalent brackets. For vertical stacks, provide a support clip within 150 mm of each socket. For horizontal runs, support spacing depends on pipe diameter — typically 500 mm for 40–50 mm pipes and up to 1,000 mm for 110 mm and larger. Always provide a support directly beneath each fitting. Do not overtighten clips on uPVC pipe — moderate firm contact is sufficient; crushing the pipe will distort the bore and impair flow.
Karachi’s trusted Dadex supplier — six reasons to choose Arfa Trading
Arfa Trading has been supplying Dadex products to contractors, developers and building owners across Karachi and Pakistan for years. Our reputation rests on one non-negotiable principle: genuine products, honest pricing, reliable service. Here is why builders and procurement managers choose Arfa Trading for their Dadex Nikasi requirements.
100% genuine Dadex products
Every pipe, fitting and accessory we supply is sourced directly from Dadex Eternit Limited’s authorized distribution network. You receive genuine, certified Dadex Nikasi products — not copies, substitutes or unverified alternatives. Each product carries the Dadex brand marking and standard code.
Full range in ready stock
We maintain comprehensive stock of the Nikasi pipe and fittings range in all six diameters (40 mm–200 mm). Both solvent cement and rubber ring fitting types are stocked. No long lead times — most orders are available for same-day or next-day collection or delivery in Karachi.
Competitive, transparent pricing
Our prices for Dadex Nikasi pipes and fittings are highly competitive across the Karachi market. We provide clear, itemized quotations with no hidden charges. Volume discounts are available for large project orders, and our pricing is consistent — no end-of-month surprises.
Technical product guidance
Our team understands the Dadex Nikasi system thoroughly. We can help you select the correct pipe size for each application, choose between solvent cement and rubber ring joint types, and identify the correct fittings for your specific drainage layout. Ask us before you buy — it prevents costly specification errors on site.
Delivery across Pakistan
We supply construction sites across Karachi and can arrange freight delivery to Lahore, Islamabad, Hyderabad, Multan, Faisalabad and other cities. Bulk project orders are prioritized and coordinated with your site schedule to ensure materials arrive when needed.
Contractor and trade accounts
Registered contractors and construction companies can apply for a dedicated trade account with Arfa Trading. Trade account holders benefit from volume pricing, reserved stock allocation for ongoing projects, and flexible payment terms. Contact us to discuss your requirements.
Everything you need to know about Dadex Nikasi — FAQ
What is Dadex Nikasi and what is it designed to do?
Dadex Nikasi is a complete unplasticized PVC (uPVC) soil, waste and vent (SWV) building pipe system manufactured by Dadex Eternit Limited. It is specifically engineered to carry the solids present in both foul water (from toilets, urinals and bidets) and surface water effluents (from sinks, baths, showers and floor drains), with minimum risk of pipe blockade. The word ‘Nikasi’ is derived from Urdu meaning drainage or outflow. Dadex Nikasi was the first complete uPVC SWV system launched in Pakistan, and it remains the country’s most widely specified drainage pipe product for building construction.
What sizes does Dadex Nikasi come in?
Dadex Nikasi pipes are available in six nominals outside diameters: 40 mm, 50 mm, 75 mm, 110 mm, 160 mm and 200 mm. Standard pipe lengths are 3 meters and 4 meters. The 40 mm and 50 mm sizes are typically used for fixture waste connections. The 75 mm size serves branch drains and vent stacks. The 110 mm size is standard for WC soil connections and main soil stacks. Sizes 160 mm and 200 mm are used for building drain collectors and connections to the municipal sewer main.
What international standard does Dadex Nikasi conform to?
Dadex Nikasi pipes conform to ISO 3633:2002(E) / EN 1329:1999 and PS 3214:1992 (Pakistan Standard). Nikasi fittings with solvent cement joints and fittings with rubber ring joints both conform to ISO 3633:2002(E) / EN 1329:1999. The solvent cement used for jointing conforms to BS 4346 Part 3. Dadex Eternit Limited as a company holds ISO 9001, ISO 14001 and ISO 45001 management system certifications, and products carry PSQCA accreditation.
What is the difference between solvent cement and rubber ring joints?
Solvent cement joints use a chemical bonding agent (BS 4346 Part 3) to permanently fuse the pipe spigot into the fitting socket — creating a rigid, waterproof joint that becomes as strong as the pipe wall. This method is standard for 40–75 mm sizes and internal applications. Rubber ring push-fit joints use a pre-fitted EPDM rubber ring inside the fitting socket to create a quick, flexible, watertight seal. Rubber ring joints are preferred for 75 mm and above, for long horizontal runs, and anywhere slight pipe movement due to thermal expansion or building settlement must be accommodated. Both joint types comply with ISO 3633:2002(E) / EN 1329:1999.
Does Dadex Nikasi resist corrosion and bacterial growth?
Yes resistance to corrosion and biological growth is one of Nikasi’s core advantages. uPVC does not corrode, rust or oxidize, unlike cast iron, mild steel or galvanized pipes which suffer progressive degradation in contact with sewage and soil chemicals. Nikasi is also resistant to organic growth — algae, bacteria and fungi do not colonies uPVC surfaces readily, which maintains the smooth bore and prevents biofilm build-up that can reduce flow capacity over time.
Is Dadex Nikasi suitable for rainwater downpipes and external drainage?
Yes. Dadex Nikasi is fully suitable for rainwater downpipes and external surface water drainage. The grey uPVC material is UV-stabilized for outdoor exposure. Sizes 75 mm and 110 mm are most commonly used for residential rainwater downpipes, while 160 mm and 200 mm pipes serve commercial roof drainage collectors and surface water gullies.
What is the difference between Dadex Nikasi and Dadex Flowline?
Nikasi is the above-ground (internal and external building) soil, waste and vent system — it handles drainage from fixtures within and around the building structure. Dadex Flowline is the underground sewer pipe system — designed for buried applications, carrying the combined drainage from a building to the municipal sewer main or a septic tank. The two systems are designed to be used together: Nikasi brings waste to ground level, Flowline takes it away underground.
What is the difference between Dadex Nikasi and Dadex Ecoplast?
Dadex Nikasi is a grey uPVC drainage pipe — designed for carrying waste water and sewage under gravity flow only. It is not pressure-rated. Dadex Ecoplast is a white uPVC pressure pipe for cold potable water supply and distribution, pressure-rated to meet ISO 1452 / BS EN 1452 requirements. Never use Nikasi for water supply — it will not withstand supply pressure. Never use Ecoplast for drainage — it lacks the fittings geometry and chemical resistance profile required for sewage applications.
How do I calculate how much Dadex Nikasi pipe I need?
Start with your plumbing engineer’s drainage layout drawing, which should specify pipe sizes for each run. For each size, measure the total linear length of pipe runs (in meters), add approximately 10% for cutting wastage. Count all fittings — bends, tees, traps, access points — and list them by size and type. For projects without a formal layout, Arfa Trading’s team can assist with an indicative pipe and fittings schedule based on your building type, number of floors and fixture count.
Where can I buy Dadex Nikasi pipes and fittings in Karachi?
Arfa Trading is a Karachi-based supplier carrying the complete Dadex Nikasi pipes and fittings range. We stock all six diameters (40 mm to 200 mm), both pipe lengths (3 m and 4 m), and the full fittings portfolio in both solvent cement and rubber ring joint types — including P-traps, bends, tees, access pipes, boss adaptors, vent cowls and all standard components. Contact us directly for current pricing, availability and delivery arrangements within Karachi or to any city in Pakistan.
Order Dadex Nikasi pipes & fittings today
Genuine Dadex products, competitive prices, all sizes in stock. Arfa Trading delivers to construction sites across Pakistan. Contact us today for a fast, itemized quotation tailored to your project requirements.
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