Kerakoll H40 Extreme hybrid two-component gel tile adhesive

In pools, chlorinated water eventually dissolves traditional adhesive bonds. On metal and aluminum, cement adhesive barely sticks — tiles detach. Where water, chemicals, and thermal movement combine, reactive bonding is needed. H40 Extreme is a two-component, hybrid adhesive — holds underwater, on metal, and under chemical exposure. This is Kerakoll H40 Extreme.

Made in Italy. Kerakoll, Sassuolo — building material innovation since 1968. H40 Extreme is the renewed H40 tile adhesive line’s hybrid, two-component member — the line’s only reactive adhesive.

• Swimming pool and chlorinated water: does not dissolve the bond — after immersion in chlorinated water still ≥ 3 N/mm² shear strength, durable underwater
• Metal, aluminum, deformable substrate: hybrid gel bond moves with it, does not detach — on aluminum heat-conductive film without primer, on metal and wood after Active Prime Grip preparation
• Industrial floor, plant, chemical exposure: the two-component hybrid formula holds — reactive bonding where traditional cement adhesive fails
• Thermal shock and temperature fluctuations: withstands between −40 °C and +90 °C — after thermal shock still ≥ 5.5 N/mm², endures heating cycles and facade temperature changes
• Large tile (up to 160x320 cm): full bedding, no hollow spots — extra fluid gel, full back wetting
• Vertical surface: tile does not slip — slip-resistant (≤ 0.5 mm), can be applied on walls and facades from top to bottom
• Adjusting large tiles, your hand stops: no rushing, no premature setting — ≈ 180 minutes open time and ≥ 120 minutes correction time for double application and precise adjustment
• Two-component but no mixing errors: no need to weigh — the monopack 10 kg packaging contains A and B parts pre-measured precisely (8.6 : 1.4)
• Working indoors, living there too: no strong vapor, no risk — A+ indoor air class, low volatile organic compound emissions, EPD certified

What is it suitable for?

Tiling materials: Gres tiles in all sizes — from 30x30 cm tiles to 160x320 cm large slabs. Thin, laminated, and resin-backed gres tiles. Ceramic, marble, natural stone, glass and glass mosaic, terracotta, clinker, metal sheet, thermal and sound insulating panels.

Substrates: Cement screed, concrete, lime and cement plaster, drywall, fiber-reinforced cement board, brick, aerated concrete. Existing, fixed, intact coverings. Underfloor heating, including screed-free, aluminum heat-conductive film preformed panels. Cracked screed. Thick-layer epoxy and polyurethane coatings. Rubber and PVC flooring (after cleaning with Keragrip Eco Pulep). Gypsum and anhydrite indoors, after EP21 dust binding.

Wood, metal, metal sheet: After preparation with Active Prime Grip — the hybrid bond holds even on deforming substrates.

Spaces: Interior and exterior, floor and wall, terrace and balcony, facade, swimming pool and fountain, sauna and wellness. Residential, commercial, industrial projects and street furniture.

Not suitable for:

• Direct contact with polystyrene (polystyrene, EPS, XPS) — the hybrid formula attacks it
• On Aquastop Nanoflex waterproof gel membrane
• For substrates that are not perfectly dry and prone to moisture penetration
• For filling substrate unevenness greater than 15 mm — first self-leveling (Planogel Ultra)

Different task? Standard tiling, large format, underfloor heating: H40 Gel. Fast handover or cold season: H40 Advanced. Facade, moving cement substrate, fabric-reinforced large format: H40 Tech.

Frequently asked questions

Why does chlorinated water dissolve tile adhesive in pools?
In a chlorinated pool continuously exposed to water, the bond of traditional cement adhesive weakens over time. The H40 Extreme hybrid tile adhesive maintains a shear strength of ≥ 3 N/mm² even after immersion in chlorinated water — tested for pools and fountains.

What is a hybrid, two-component tile adhesive?
A reactive adhesive that must be mixed from two parts — A and B — before use. The setting is not triggered by water but by the reaction of the two components. That’s why it adheres where ordinary cement adhesive fails: underwater, on metal, under chemical exposure.

Which tile adhesive is needed for metal or aluminum substrates?
A reactive, hybrid tile adhesive is required for metal and aluminum substrates — H40 Extreme. The hybrid gel bond moves with the metal’s thermal expansion and does not delaminate. It adheres to aluminum heat-conductive film without primer, and to metal and wood after Active Prime Grip preparation.

What does the R2 T class and GT-3 rating mean?
R2 T is the EN 12004 classification: R = reactive adhesive, 2 = improved performance, T = reduced slip. GT is Kerakoll’s own system test for torsion and bending — GT-3 is the highest flexibility rating.

When is H40 Extreme needed and when is a simpler tile adhesive enough?
H40 Extreme is for when water, chemicals, or metal substrates are all involved: pools, industrial floors, aluminum panels. For standard tiling on smooth cement substrates, H40 Gel is simpler and more economical — it is one-component, only water needs to be added.

Why is the hybrid tile adhesive more expensive than the traditional one?
Because it is a two-component, reactive formula — it adheres even where cement adhesive fails: underwater, on metal, under chemical exposure. Repairing a delaminated pool lining or industrial floor costs many times more than the adhesive itself. Where there is no such exposure, H40 Gel is cheaper and sufficient.

When should I not choose H40 Extreme?
It cannot be applied directly on polystyrene (EPS, XPS) insulation and does not fill substrate defects larger than 15 mm — for these, a self-leveling compound is needed first (Planogel Ultra). On smooth cement substrates without water or chemical exposure, H40 Gel is more economical.

How many m² does a 10 kg monopack cover?
Material requirement ≈ 1.45 kg/m²/mm layer thickness. A 10 kg package covers approximately 1.4-1.7 m² on small tiles (4-5 mm bedding) and 0.7-0.85 m² on large slabs (8-10 mm, two coats).

When can you walk on it and fill the pool?
At +23 °C, the surface is walkable and grouting is possible after ≈ 4 hours. Pools can be filled after ≈ 3 days. The substrate must first have Kerakoll waterproofing — H40 Extreme bonds to that.

How to mix the two-component adhesive?
The monopack contains both parts pre-measured — in an 8.6 : 1.4 ratio. Part B must be poured from the B bucket into part A, then mixed until the color is uniform. Before use, keep the packaging at ≈ +20 °C for 2-3 days.

Can I apply it myself?
You can apply it, but the two-component mixing and hybrid application must be done precisely — especially in pools, on metal substrates, with large tiles. For underfloor heating and critical substrates, rely on our Kerakoll-certified tiling master; we also offer installation services.

H40 System

H40 is the Kerakoll structural gel adhesive line — every member tested with the GT method, suitable for porcelain, ceramic, and natural stone. All are suitable for indoor and outdoor use, underfloor heating, terraces, and swimming pools. Extreme is the only hybrid, two-component reactive member of the line.

H40 tile adhesive line — which one do you need?

See the entire H40 family in the tile adhesives category. The system is completed with Color Fill decorative grouts.

Primers: on gypsum and anhydrite substrates, EP21 dust binding is required before bonding (indoor use only). On wood, metal, and PVC substrates, Active Prime Grip preparation is necessary. H40 Extreme can be applied without primer on aluminum heat-conductive film.

Waterproofing: in wet areas and pools, H40 Extreme provides a monolithic, waterproof system with the Kerakoll waterproofing product line.