GIB Aqualine® – as a Substrate for Wet Area Tiling

GIB Aqualine® - as a Substrate for Wet Area Tiling
Published: 18 August 2020

GIB Aqualine® is part of a system that protects areas where there is intermittent water exposure and areas prone to water splashing within residential and non-residential buildings – in particular, areas covered by the New Zealand Building Code (NZBC), Clause E3 Internal Moisture.

Although able to cope with infrequent short-term exposure, standard gypsum plasterboard will have a shortened life expectancy when frequently exposed to water or moisture.

It is highly desirable to incorporate lining materials that will maintain their integrity longer when exposed more frequently to water, or steam, and particularly to one-off events such as a plumbing leak causing the flooding of a room. GIB Aqualine® is ideal in such situations because it features a water resistant core.

Unlike other commonly used substrates, the GIB Aqualine® core not only resists penetration of water through the lining into the framing behind, but also resists water “wicking” up the core, a common cause of long-term damage where a water resistant lining has not been used. GIB Aqualine® will maintain its integrity for extended periods, particularly where wicking over large areas can destroy the integrity of the interface between the lining and paint or wallpaper surfaces or between the lining and the tile adhesive.

Because GIB Aqualine® is dimensionally stable and resistant to water damage, it is an ideal substrate for tiling in residential wet areas. 10mm and 13mm GIB Aqualine® are suitable for tile weights up to 20kg/m² on timber framing, and 13mm GIB Aqualine® on steel framing and for tile weights between 20 and 32kg/m².

Liquid applied water proof membranes and tile adhesives readily adhere to the GIB Aqualine® face liner and GIB® jointing compounds. It is important, though, to use a water proof membrane that is compatible with the GIB Aqualine® and the tiles. The Wet Area Systems book and the GIB® Site Guide provide further information to help.

GIB Aqualine® Benefits

  • Dimensionally stable, will not buckle or warp, hence an excellent substrate for ceramic tiles.
  • Water resistant and durable to help protect against water damage.
  • Suitable for both residential and non-residential applications.
  • Conventional jointing methods.
  • Easy to cut and form openings.
  • Contains fibreglass and other additives for strength and fire resistance. May be used in GIB® Bracing, GIB® Fire Rated and GIB Noise Control® Systems (see Compliance with the NZBC, Clauses B1, C3 and G6). Consult the appropriate GIB® literature for installation details.
  • Green face paper for ease of recognition.


  • GIB Aqualine® must not be used for bracing purposes in shower cubicles or above baths.
  • Do not use GIB Aqualine® where it may be exposed for extended periods to humidities of 90 percent RH and above. Such areas include group shower or steam rooms as well as moisture and chlorine rich environments such as indoor swimming pools.
  • GIB Aqualine® must not be directly applied to solid plaster (gypsum or cement), wood based sheet linings or similar materials, masonry or concrete. GIB Aqualine® may only be applied to these materials where timber strapping or steel furring channels are installed.
  • GIB Aqualine® must not be installed over a vapour barrier or a wall acting as a vapour barrier.
  • Cracked or damaged sheets must never be used.
  • GIB Aqualine® must not be used in external applications.
  • GIB® plasterboard must not be exposed to temperatures in excess of 52°C for prolonged periods. Heat-generating devices may include halogen lighting, cooking elements, radiant heating, solid fuel exhausts and fire surrounds. Consult the appliance manufacturer for installation details.

For more information, see: