Mapei Ultralite Rapid Flex S1 15kg


From: £33.44 inc. VAT
£27.87 ex. VAT

Checkout
  • Suitable For: installing anti-fracture membrane and all types of ceramic tiles
  • Area of use: INT & EXT
  • Application Method: trowel
  • Volume: 15KG
  • Container Type: bag
  • Type: adhesive
  • Colour: 2 colours
  • Brand: Mapei
  • Manufactuer: Mapei
  • Box Size: 1

 

Ultralite Rapid Flex S1 is a rapid-setting, flexible, low-dust adhesive with non-slip properties, ideal for installing ceramic, porcelain, and natural stone tiles on walls and floors, especially thin porcelain tiles. Developed with Mapei’s advanced Low Dust technology and more than 30% recycled materials, it offers up to 60% greater coverage than traditional adhesives, making it a sustainable, easy-to-handle option for both indoor and outdoor applications. Its lightweight, thixotropic formula ensures excellent grab on vertical surfaces, is compatible with various substrates, and maintains strength under thermal changes and moisture, ideal for high-traffic, wet areas.

 

Key points:

  • Contains over 30% recycled material and reduces dust emissions, contributing to better air quality and sustainability.
  • Lightweight, with 60% higher yield than conventional adhesives, enhancing ease of handling and transport.
  • Flexible, durable adhesive bed suitable for use with underfloor heating, swimming pools, and waterproofing systems.
  • Strong bond across standard wall and floor substrates, excellent non-slip properties, and easy application for vertical and large-format tiles.

 

 

 

For more information about Mapei and their products, please visit their website here.

For our full Mapei range, click here. For more in our range of adhesives, click here.

 

 

Ultralite Rapid Flex S1 is suitable for installing MAPEI Mapetex anti-fracture membrane and all types of ceramic tiles and mosaics, including double-fired, single-fired, porcelain, clinker, and terracotta, on both even and uneven interior or exterior surfaces, up to 15 mm thickness. It can be used for installing natural stone tiles and mosaics on indoor and outdoor surfaces, provided the stone is not moisture-sensitive or prone to discoloration. Ideal for thin, non-mesh-backed porcelain tiles on interior and exterior walls and floors, following tile manufacturer guidelines.

Application examples:

  • Fixing ceramic, natural stone, terracotta, and thin porcelain tiles on prepared substrates like cement-based screeds, concrete walls, heated screeds, cement and lime renders, gypsum plaster (with primer), and waterproof membranes (e.g., Mapelastic systems).
  • Suitable for installations over existing ceramic, terrazzo, or stone floors, or floors overlaid with 15 mm exterior-grade plywood.
  • Effective for balconies, terraces, and areas with restricted ventilation or limited dust tolerance, withstanding weathering, sunlight, and temperature fluctuations.

 

 

Preparation of the Substrate
Substrates for Rapid Set must be dry, stable, and free from contaminants such as grease, dust, and loose materials that could hinder adhesion. Concrete substrates should be at least 6 weeks old, and cement screeds should cure for a minimum of 3 weeks before tiling begins. Rapid drying and setting screeds made with MAPEI binders, including Topcem and Mapecem, are suitable for this product, as are pre-blended options like Topcem Pronto and Mapecem Pronto. Abraded calcium sulphate screeds should be vacuumed and primed with Eco Prim T Plus (diluted 1:2 with water) and must have a moisture content of 0.5% or lower. For flooring-grade asphalt, ensure it has sufficient strength and prime with Eco Prim Grip Plus. Alternatives to plywood for timber base overlays include a minimum of 10 mm moisture-stable cement-based tilebacker boards, while P5-grade chipboard should be securely fixed, movement-free, and primed with Eco Prim Grip Plus. Other substrates, like plaster and construction boards, must be fully dry and, if porous, primed with Primer G to control suction and prevent adhesive skinning. In damp or shower areas, protect the substrate with a MAPEI waterproofing coating, avoiding bitumen-based options. When using underfloor heating systems, level cables with Ultraplan Renovation Screed3240. Hot water piped underfloor systems should be commissioned before tiling.

 

Preparation of the Mix
Add 5.7-6.3 liters of water per 15 kg of Ultralite Rapid Flex S1 (grey) or 5.1-5.6 liters per 15 kg (white) to a clean mixing vessel. Mechanically mix until smooth and lump-free, then allow to stand for 3 minutes before remixing briefly. The mix has a pot life of approximately 45 minutes. Do not add extra water once the product begins to set.

 

Applying the Product
Apply Ultralite Rapid Flex S1 using a notched trowel to ensure full coverage of the tile backs. Begin with a thin layer on the substrate, then add the required thickness, selecting a trowel suited to the tile size. For floors and wet areas, also spread adhesive on the tile backs to ensure complete coverage. When laying thin porcelain tiles, back-buttering is recommended to prevent gaps and minimize fracture risk.

 

Installing the Tiles
Install tiles dry, wiping any dust from their backs with a damp sponge. Use firm pressure and a slight sliding action when fixing to ensure contact. The open time for Ultralite Rapid Flex S1 is about 15-20 minutes under normal conditions, though it may be shorter in high heat or on absorbent substrates. Continuously check for adhesive skinning, removing any affected layers before reapplying fresh material. Do not add water or new adhesive over a skinned layer. Final tile adjustments should be made within 15 minutes, and installations should be protected from rain for 3 hours and freezing conditions for 24 hours.

 

Reviews

There are no reviews yet.

Be the first to review “Mapei Ultralite Rapid Flex S1 15kg”

Elementlength
up to
1,5 m
up to
2,5 m
up to
3,5 m
up to
4,5 m
up to
2,5 m
up to
3,5 m
up to
4,5 m
Type of window frame material Minimum witdth of joints
for a butled mounting b in mm
Minimum witdth of joints
for a inner mounting b in mm
Hard PVC (white) 10 15 20 25 10 10 15
Hard PVC and PMMA (dark)
(colour extruded)
15 20 25 30 10 15 20
Hard PUR integral foam 10 10 15 20 10 10 15
Wood-aluminium-window 10 10 15 20 10 10 15
Aluminium-plastic sandwich
frame (bright)
10 10 15 20 10 10 15
Aluminium-plastic sandwich
frame (dark)
10 15 20 25 10 10 15
Wooden window frame 10 10 10 10 10 10 10

From: £3.11 inc. VAT
£2.59 ex. VAT

From: £3.11 inc. VAT
£2.59 ex. VAT
Select options This product has multiple variants. The options may be chosen on the product page

From: £8.03 inc. VAT
£6.69 ex. VAT

From: £8.03 inc. VAT
£6.69 ex. VAT
Select options This product has multiple variants. The options may be chosen on the product page

From: £10.07 inc. VAT
£8.39 ex. VAT

From: £10.07 inc. VAT
£8.39 ex. VAT
Select options This product has multiple variants. The options may be chosen on the product page

From: £3.11 inc. VAT
£2.59 ex. VAT

From: £3.11 inc. VAT
£2.59 ex. VAT
Select options This product has multiple variants. The options may be chosen on the product page

From: £6.59 inc. VAT
£5.49 ex. VAT

From: £6.59 inc. VAT
£5.49 ex. VAT
Select options This product has multiple variants. The options may be chosen on the product page

From: £3.11 inc. VAT
£2.59 ex. VAT

From: £3.11 inc. VAT
£2.59 ex. VAT
Select options This product has multiple variants. The options may be chosen on the product page

From: £2.86 inc. VAT
£2.38 ex. VAT

From: £2.86 inc. VAT
£2.38 ex. VAT
Select options This product has multiple variants. The options may be chosen on the product page

From: £2.69 inc. VAT
£2.24 ex. VAT

From: £2.69 inc. VAT
£2.24 ex. VAT
Select options This product has multiple variants. The options may be chosen on the product page

  • £3.19 inc. VAT
    £2.66 ex. VAT

    £3.19 inc. VAT
    £2.66 ex. VAT
      Bond-It De-Bond Mate is A non-drip gel formula for the complete removal of cured silicone sealant, particularly when silicone has been accidentally smeared over glass, ceramics or countertops. Removes all types of silicone sealant, leaving surfaces ready for re-sealing.     For all other Bond-it products on our website, please click here. For any further information, you may need on Bond-it, please visit their website here.

  • £2.94 inc. VAT
    £2.45 ex. VAT

    £2.94 inc. VAT
    £2.45 ex. VAT
      Bond-it Flash Mate Lead Silicone is a low modulus neutral cure fast-skinning, roof sealant  It is a high-performance neutral cure silicone sealant, specifically designed for use with roofing products both modern and traditional.     For all other Bond-it products on our website, please click here. For an alternative silicone for lead, click here. For any further information you may need on Bond-it, please visit their website here.

  • £9.06 inc. VAT
    £7.55 ex. VAT

    £9.06 inc. VAT
    £7.55 ex. VAT
      Everbuild 565 Clean Room Silicone is a neutral cure, low modulus, odourless sealant that adheres to a wide range of surfaces. Advantages - Mould Resistant for up to 10 years. - Bacterial resistance. - Excellent tooling and slow skinning properties. - Excellent adhesion properties to most surfaces. - Non-slump formula. - Excellent weathering properties.     For application guns click here. For application tools click here. For all other Everbuild products on our website, please click here. For any further information on Everbuild products, please visit

  • £6.78 inc. VAT
    £5.65 ex. VAT

    £6.78 inc. VAT
    £5.65 ex. VAT
      Everbuild Aqua Mate Sealant is a high modulus, reactive curing silicone sealant specially designed for aquariums. It remains permanently flexible & forms a watertight seal. Advantages - Everbuild Aqua Mate is free from fungicide and solvent - will not harm fish. - Fast cure - gives quick early strengths. - Extremely low dirt pick up. - Will withstand continuous water immersion.   For application guns for this product, please click here. For all other Everbuild products on our site, please view here. For any further information on any Everbuild products, ple