Roca Bathrooms Duplo One Underwindow Cistern Tank, Concealed WC Flush Tank, Toilet Cistern Reservoir, Replacement Spares

Name: Roca Bathrooms Duplo One Underwindow Cistern Tank, Concealed WC Flush Tank, Toilet Cistern Reservoir, Replacement Spares
Brand: BHL
SKU: W-D41012
Price: 156.18 GBP
Availability: InStock

SKU W-D41012

Manufacturer part number: A8900722A0
EAN: 8445662060825

£156.18

inc VAT£130.15 ex VAT

Lead time: 1-5 working days

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Description

Product Overview

The Roca Bathrooms DUPLO ONE CISTERN TANK UNDERWINDOW (AG) is a concealed WC cistern tank designed for under-window installations where height is limited. Ideal for replacement or new installs, it helps deliver reliable flushing performance while keeping your bathroom looking clean and modern.

Key Features

Under-window design – suitable for low-height installations to maximise space and fit where standard cisterns will not.
Concealed cistern tank – keeps pipework and the flush reservoir hidden for a neater, minimalist bathroom finish.
Genuine matched part – designed for compatibility within the Duplo One system, helping reduce fitting issues during replacement.
Reliable flush water storage – provides consistent performance for everyday toilet use in busy household bathrooms.

Use Case / Application

Designed for use in domestic and commercial bathrooms where a concealed cistern is required, particularly in under-window WC layouts. Suitable for installation behind a wall, in boxing, or within a furniture/false-wall arrangement as part of a modern concealed toilet setup. Commonly used in:

Downstairs cloakrooms and compact en-suites
Main family bathrooms with limited wall height
Commercial washrooms using concealed WC systems
Replacement projects where an existing Duplo One cistern tank needs renewing

Problem → Solution

Perfect for under-window bathrooms where a standard-height concealed cistern will not fit, providing a space-saving solution without compromising on everyday flushing reliability.

Product Specifications

Manufacturer – Roca Bathrooms
Manufacturer Part Number (MPN) – A8900722A0
EAN / Barcode – 8445662060825
Manufacturer Range / Series – Duplo One
Product Type – Concealed cistern tank (underwindow)

Why Buy from BHL

Roca Bathrooms is a trusted name in modern bathroom solutions, known for quality engineering and dependable performance. Choose this Duplo One underwindow cistern tank for a like-for-like replacement and a tidy concealed finish. Buy online from BHL for competitive pricing, free* and fast UK delivery, and genuine parts delivered with care from UK warehouses. BHL is a specialist online merchant trusted by thousands of satisfied customers since 1998, with thousands of 5 star reviews. *see our terms

Reviews

Buying guide: Toilet Cisterns & Pans

This category covers the main parts of a toilet: close coupled, back to wall and wall-hung pans, close coupled and concealed cisterns, and the flush valves, fill valves, flush plates, pan connectors and fixing kits that go with them.

Pan and cistern styles

Close coupled: the cistern sits directly on the back of the pan to form one suite.
Back to wall: the pan sits tight against the wall, with the cistern concealed in furniture or a boxed-in duct.
Wall-hung: the pan is carried on a frame built into the wall, with a concealed cistern worked by a flush plate.
Raised height: taller pans, often chosen for accessible bathrooms.

Matching parts

Pans and cisterns are usually designed in pairs, so check that a replacement is listed as compatible with the other half. Note whether the cistern is fed from the bottom or the side, and whether the overflow is internal, into the pan, or external. Pan connectors join the pan outlet to the soil pipe and come straight, offset and angled to suit the pipe position. For replacement flush and fill valves, match the cistern's outlet size and flush type, single or dual.

Standards and regulations

In England and Wales, under the Water Supply (Water Fittings) Regulations 1999, a single WC flush must not exceed 6 litres, and every WC cistern inlet needs a servicing valve next to the cistern. Dual flush cisterns of 6/4 and 4/2.6 litres are common. Pans with an integral trap, and close coupled suites, are covered by BS EN 997, and separate flushing cisterns by BS EN 14055.

For toilet seats, see toilet seats, or browse complete toilets.

Shop all Toilet Cisterns & Pans