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Ardex X78 Microtec Standard Tile Adhesive Grey 20kg
Ardex X78 Microtec Standard Tile Adhesive Grey 20kg

Ardex X78 Microtec Standard Tile Adhesive Grey 20kg

Non-Stock 5-7 Working Days

Product Options:

Description

ARDEX X 78 Semi-Pourable Floor Tile Adhesive

ARDEX X 78 has been specifically engineered to suit modern large-format tiles, offering a semi-pourable consistency that provides a solid bed fix without the need for back-buttering. Its high yield, extended open time, and easy workability make it ideal for commercial and residential floor applications — both internal and external, including swimming pools and areas with underfloor heating.

Key Features

  • MICROTEC® fibre-reinforced for superior strength and flexibility
  • Ideal for large format floor tiles and solid bed fixing
  • Extended open time – up to 60 minutes
  • Long pot life – up to 3 hours
  • High yield – covers up to 5.6 m² at 3 mm thickness per 20 kg bag
  • Suitable for internal and external use, including swimming pools
  • Compatible with underfloor heating systems
  • Low embodied carbon: 0.49 kg CO₂ eq/kg (A1–A3 production stage)

Technical Data

Property ARDEX X 78 Specification
Product Type MICROTEC® Fibre-Reinforced Semi-Pourable Floor Tile Adhesive
Colour Grey
Unit Size 20 kg
Classification BS EN 12004 C2 E – Improved Cementitious Adhesive with Extended Open Time
Bed Thickness 1 – 6 mm
Pot Life ≈ 3 hours @ 20 °C
Open Time Up to 60 minutes
Adjustment Time Up to 30 minutes
Groutable After 24 hours @ 20 °C
Coverage ≈ 5.6 m² per 20 kg bag @ 3 mm thickness
Yield ≈ 16.65 L of mortar per 20 kg bag
Fresh Mortar Density ≈ 1.6 kg/L
Tensile Adhesion Strength (28 days dry) ≥ 1.0 – 2.0 N/mm²
Tensile Adhesion Strength (after water immersion) ≥ 1.0 N/mm²
Tensile Adhesion Strength (after freeze/thaw) ≥ 1.0 N/mm²
Underfloor Heating Compatibility Yes – suitable for heated floors
External Use Yes – including swimming pools and wet areas
Embodied Carbon 0.49 kg CO₂ eq/kg (A1–A3 stage)

Surface Preparation & Application

Ensure the substrate is clean, firm, and free from contaminants. ARDEX X 78 can be applied to dry or slightly damp substrates but must not be used on moisture-sensitive materials unless they are completely dry. For waterproofing, use the ARDEX WPC Waterproof Protection System prior to tiling.

Mix approximately 7.2 litres of clean water per 20 kg bag using a paddle mixer until a smooth, pourable consistency is achieved. Apply with a notched trowel and fix tiles within the adhesive’s open time. Tiles can be adjusted for up to 30 minutes.

Grouting & Finishing

Grouting can commence after 24 hours using ARDEX-FLEX Tile Grout or ARDEX EG8 Epoxy Hybrid Grout for hygienic or chemical-resistant applications.

Common FAQs

Can ARDEX X 78 be used outdoors?
Yes, it is suitable for internal and external applications including wet areas and swimming pools.
Is ARDEX X 78 suitable for underfloor heating?
Yes, it can be used with most heated screeds and underfloor heating systems.
Do I need to back-butter large tiles?
The semi-pourable consistency usually provides full coverage without back-buttering, except for very uneven or textured tiles.
How soon can I grout after fixing?
Normally after 24 hours at 20 °C, depending on the tile and substrate porosity.
What primer should I use before applying ARDEX X 78?
Use ARDEX P 51 for absorbent backgrounds or ARDEX P 4 for smooth, non-absorbent surfaces.

Delivery & Returns

Delivery Information

Delivery Costs:

Delivery fees are calculated based on the weight of your order and your delivery location. You can use the delivery fee calculator in your basket or on the checkout page to find the exact cost.

Delivery Area:

We currently only deliver to UK Mainland and the Highlands. We do not deliver to the Islands, Ireland, or Northern Ireland.

Next Working Day Delivery (Subject to Stock Availability):

Orders placed before 12:00 pm (noon) will be delivered the next working day, excluding weekends and holidays. This service starts from £6.50 (including VAT) and the final cost is based on the weight of your order and your delivery location. You can check the exact cost in your shopping cart or on the checkout page by entering your postcode.

Cut-off Time for Genesis Products (Non-Stocked): 11:00 am

NO Next Day Service - Scotland:

We are unable to offer next-day service to the following postcode regions in Scotland.

Postcode: AB, IV, KW, PA .

Economy Service (2-3 Working Days):

This service is only available for orders over 50kg. There is no additional charge for this service.

Sample Orders:

All sample orders are shipped for free via Royal Mail Tracked 48 or 24 service. Delivery typically takes 1-3 working days.

Delivery Methods:

Non-sample orders under 50kg will be dispatched via DPD or APC Overnight. Non-sample orders over 50kg (quarter, half, and full pallets) will be dispatched via Palletways or Kandrmason (Kerbside delivery only).

Order Online & Collect In-Store!

Simply place your order online and choose the Click & Collect option at checkout.

We'll email you once your order is ready for pickup at your chosen store.

Collection hours: Monday - Friday: 8:30 am to 4:30 pm

For more information, please visit our Delivery Information page.

Returns Information
  • Please inspect your order upon receipt and contact us immediately (within 48 hours of receipt) if the item is defective, damaged, or if you receive the wrong item, so that we may evaluate the issue and make it right.
  • We will replace any items that are damaged during transit within 30 days of delivery.
  • We accept returns within 30 days of delivery.
  • Please note that customers are responsible for the cost of returning items where the return is due to a change of mind, including ordering the wrong item, ordering more than required, or any other non-fault reason
  • We will process returns and refunds promptly once the items are received at our warehouse.

Returning Trims

Schluter Trims:

  • Returning trims - 35% restocking fee applied.
  • Returning trim with replacement - 15% restocking fee applied.
  • Customers are responsible for arranging the return.
  • If we arrange a return collection, a £35 return item collection fee will be applied.

Mapei-Profilpas Trims:

  • A 20% restocking fee will be applied (item must be in re-sellable condition).
  • The customer is responsible for returning the item.

For more information, please visit our Return & Exchange page.

Delivery Costs:

Delivery fees are calculated based on the weight of your order and your delivery location. You can use the delivery fee calculator in your basket or on the checkout page to find the exact cost.


Delivery Area:

We currently only deliver to UK Mainland and the Highlands. We do not deliver to the Islands, Ireland, or Northern Ireland.


Next Working Day Delivery (Subject to Stock Availability):

Orders placed before 12:00 pm (noon) will be delivered the next working day, excluding weekends and holidays. This service starts from £6.50 (including VAT) and the final cost is based on the weight of your order and your delivery location. You can check the exact cost in your shopping cart or on the checkout page by entering your postcode.


Cut-off Time for Genesis Products (Non-Stocked): 11:00am


Economy Service (2-3 Working Days):

This service is only available for orders over 50kg. There is no additional charge for this service.


Sample Orders:

All sample orders are shipped for free via Royal Mail Tracked 48 or 24 service. Delivery typically takes 1-3 working days.


Delivery Methods:

Non-sample orders under 50kg will be dispatched via DPD or APC Overnight. Non-sample orders over 50kg (quarter, half, and full pallets) will be dispatched via Palletways or Kandrmason (curbside delivery only).


ORDER ONLINE & COLLECT IN-STORE!

Simply place your order online and choose the Click & Collect option at checkout.
We'll email you once your order is ready for pickup at your chosen store.
Collection hours: Monday - Friday: 8:30 am to 4:30 pm


For more information, please visit our Delivery Information page.

- Please inspect your order for any damages upon delivery and notify us immediately if you find any.

- We will replace any items that are damaged during transit.

- We accept returns within 30 days of delivery.

- Please note that customers are responsible for the cost of returning items.

- We will process returns and refunds promptly once the items are received at our warehouse.


Returning Trims
Schluter Trime
Returning trims - 35% restocking fees applied.
Returnign trim with replacement - 15% restocking fees applied
Customers are responsible to arrange returning the item.
If we arrange a return colleciton, a £35 return item collection feed will be applied.


Mapei-Profilpas Trims
A 20% restocking fee will be applied. (Item must be in re-sellable condition)
The customer is responsible for returning the item.


For more information, please visit our Return & Exchange page.

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