Underlay Plus Wetroom Kit for Tiled Floors

A complete wetroom system for tiled floors, combining the Underlay Plus floor former, high-flow drain and paint-on tanking system in one kit.

Manufactured from durable high-density XPS with a tough, impact-resistant surface, Underlay Plus provides a lightweight wetroom solution for timber or solid floors and is available in a wide range of sizes and drain positions.

All components are also available separately.

From 22m Thick | 43 L/min Drain | 20 x 20mm Minimum Tile Size | Up to 10m² Tanking

Underlay Plus wetroom kit for tiled floors

Underlay Plus Key Features

High-strength XPS construction
Tough, impact-resistant surface
Suitable for timber floors with suitable support underneath
Suitable for solid floor installations
High compressive strength allows tiles from 20 × 20mm
Adjustable drain grid height
Factory-fitted gasket provides secondary waterproofing.
Built-in falls direct water towards the drain
Can be cut to size where required
Manufactured in the UK

What's Included in the Maxxus Kit?

Underlay Plus wetroom former
Underlay Plus drain kit
Choice of drain grid
9kg Innovations paint-on tanking system
Installation instructions

Sizes

800 x 800 x 22mm

DTK80

900 x 900 x 22mm

DTK90

1000 x 1000 x 22mm - Centre

DTK10-C

Underlay Plus Wetroom Tray 1000 x 1000mm Centre

1000 x 1000 x 22mm - Offset

DTK10-O

Underlay Plus Wetroom Tray 1000 x 1000mm Offset

1200 x 800 x 22mm

DTK128

1200 x 900 x 22mm - Centre

DTK129-C

Underlay Plus Wetroom Tray 1200 x 900mm Centre

1200 x 900 x 22mm - Offset

DTK129-O

Underlay Plus Wetroom Tray 1200 x 900mm Offset

1200 x 1000 x 22mm

DTK121

Underlay Plus Wetroom Tray 1200 x 1000mm

1200 x 1200 x 22mm - Centre

DTK12-C

Underlay Plus Wetroom Tray 1200 x 1200mm Centre

1200 x 1200 x 22mm - Offset

DTK12-O

Underlay Plus Wetroom Tray 1200 x 1200mm Offset

1500 x 800 x 27mm

DTK158

1500 x 900 x 27mm

DTK159

1500 x 1050 x 25mm

DTK1510

Underlay Plus Wetroom Tray 1500 x 1050mm

1600 x 900 x 27mm

DTK16

1800 x 900 x 27mm - Centre

DTK18-C

Underlay Plus Wetroom Tray 1800 x 900mm Centre

1800 x 900 x 27mm - Offset

DTK18-O

Underlay Plus Wetroom Tray 1800 x 900mm Offset

2000 x 1000 x 32mm

DTK20

1500 x 1500 x 27mm

DTK1515

Underlay Plus Wetroom Tray 1500 x 1500mm

Why Choose an Underlay Plus Wetroom Former?

Underlay Plus is a lightweight, non-structural wetroom former designed to create the correct falls towards the drain while providing a strong, tile-ready surface.

Unlike a structural former such as Maxxus, Underlay Plus must be fully supported underneath. Its XPS construction makes it easy to handle and cut on site, while the wide range of sizes and drain positions makes it suitable for many different wetroom layouts.

Suitable for Timber & Solid Floors

Underlay Plus can be installed on timber or solid floor constructions. On timber floors, the former must be fully supported underneath in accordance with the installation instructions. For solid floors, the former can be recessed to help create a level-access tiled shower area.

Underlay Plus Wetroom Drain

The kit includes the Underlay Plus wetroom drain with an adjustable grid height to accommodate the finished tiled floor.

Flow Rate: 34 Litres/minute

Connection: 40mm solvent weld

Water Seal: 50mm

Grid Height: Adjustable

Includes: Standard grid & drain fitting aid

Underlay Plus Drain Installation Drawing

Tile Insert Grid Options

Upgrade to a tile insert grid for a more discreet drain finish that coordinates with the surrounding tiled floor.

Stainless Steel

Code - GUTI

Underlay Plus Stainless Tile Insert Grid GUTI

Brushed Brass

Code - GUBB

Underlay Plus Tile Insert Brass Grid GUBB

Bronze

Code - GUBZ

Black

Code - GUMB

Complete Wetroom Tanking System Included

Every Underlay Plus tiled-floor kit includes our Innovations paint-on tanking system, providing a continuous waterproof membrane across the wetroom floor and surrounding wet area before tiling.

innovations 9kg paint-on wetroom tanking system

Included:

9kg tanking liquid
10m joint tape
2 internal corners
2 pipe collars
1 litre primer
Application brush

Up to 10m² Coverage | No Mixing Required | Flexible Membrane | Suitable with Underfloor Heating

Underlay Plus Installation Instructions

Always read the installation instructions before beginning work and check that the former, drain and floor construction are suitable for the intended installation.

Underlay Plus Installation Instructions

Need Help? Contact Technical Support

Underlay Plus Wetroom Kit FAQs

Is Underlay Plus a structural wetroom former?

No. Underlay Plus is an XPS wetroom former and must be fully supported underneath. If you require a self-supporting structural former, consider our Maxxus wetroom system.

Can Underlay Plus be installed on timber floors?

Yes. Underlay Plus is suitable for timber floor installations, but the former must be correctly supported underneath in accordance with the installation instructions.

Can Underlay Plus be installed on concrete floors?

Yes. Underlay Plus can be installed into suitable solid floor constructions and recessed where required to create a level-access tiled shower area.

What is the minimum tile size for Underlay Plus?

The high-compressive-strength surface allows tiles and mosaics from 20 × 20mm to be installed, using a suitable tile adhesive.

Can the Underlay Plus former be cut to size?

Yes. The former can be cut where required to suit the available space, taking care to maintain the necessary falls towards the drain.

Does Underlay Plus need tanking before tiling?

Yes. The wetroom must be correctly waterproofed before tiling. The kit includes our paint-on tanking system for waterproofing the former and surrounding wet area.