1.6 mm Aquastop

Thin and high-performance
Its thin design makes SELITFLEX® 1.6 mm AquaStop an excellent choice for combination with underfloor heating. Despite its slim design, the underlay offers very good sound insulation values and reliably protects your floor from damage caused by falling objects. The integrated vapour barrier stops rising moisture. With pre-laminated silent laminate floors, SELITFLEX® 1.6 mm AquaStop is used as an additional underlay to level out small uneven areas.

Polystyrene foam with good compressive strength – ideal for underfloor heating

  • Protects against falling objects
  • Good impact and walking sound insulation
  • Suitable for underfloor heating systems
Order number70620
Thickness1.6 mm
Dimensions1 x 25 m
Package contents25 m²
Why 1.6 mm Aquastop

Easy to process

Easy to cut
due to printed grid

Protects the floor from damage

Protection against
loads and use

Protection against
falling objects

Protection against
rising moisture

Protection in
uneven areas

Increases living comfort

Suitability for
underfloor heating*

Reduction of
walking sound

Reduction of
impact sound

Installing 1.6 mm Aquastop –

a step-by-step guide

Before installation, please note: check the base in accordance with CEN/TS 14472 and ensure that the quality of the base is suitable for proper processing. In general, the base should be clean, level, dry, resistant to tension and compression and should not contain any substances such as plasticisers, solvents or other diffusing substances. It must be ensured that the base is in a state of equilibrium humidity and that the CM value is below 2.0 % (for cement screed) or below 0.5 % (for anhydrite screed and anhydrite flowing screed).

Cleaning the surface

Cleaning the surface

Step 1
Clean the surface thoroughly with a brush or vacuum cleaner. Remove any adhesive and paint residues completely.

Laying out the first panel

Laying out the first panel

Step 2
Lay the first panel of the underlay flush with the wall over the entire width of the room. Make sure that the aluminium side is at the top.

Masking joints

Masking joints

Step 3
To protect against moisture, seal possible joints with SELITstop® Aluminium-Foil Sealing Tape to make the joints vapour-tight.

Masking the wall connection area

Masking the wall connection area

Step 4
Tape the wall connection area with SELITstop® Moulding Protection Belt to protect against moisture.

Installing the flooring

Installing the flooring

Step 5
Lay the flooring in the same orientation as the underlay. Do not place any load on the underlay. If necessary, place the board under your knees/feet to distribute the load.

Finishing the installation

Finishing the installation

Step 6
Repeat steps 2 – 5 until the entire floor has been installed. Use the overlap and the adhesive strip to affix the individual panels of the underlay together. Cover any further joints with the Aluminium-Foil Sealing Tape to make them vapour-tight.

Technical data (according to EN 16354)
Punctual conformability (PC)up to 1 mm
Compressive strength (CS)≥ 60 kPa
Compressive creep (CC)≥ 5 kPa
Dynamic load (DL25)≥ 100,000 cycles
Resistance to large ball (RLB)≥ 90 cm
Water vapour diffusion resistance (SD)≥ 100 m
Thermal resistance (R)∼ 0.060 m²K/W
Impact sound reduction (IS)up to 20 dB
Reaction to fire (RTF)Efl
*Suitability for underfloor heatingYes, if flooring R ≤ 0,09 m²K/W (e.g. laminate up to approx. 12 mm, wood flooring up to approx. 14 mm)

Meets the minimum requirements of the EPLF and MMFA (Group 1)


SELITFLEX 1,6 mm AquaStop Produktinformationsblatt
Size: 2 MB
SELIT Catalogue 2021
Size: 7,8 MB
Excellent quality
Made in Germany.

Emissions-tested: A+

In accordance with the French VOC regulations, our underlays achieve the lowest emission values and therefore feature the A+ mark.
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Approved by the building authorities

Stay on the safe side with SELIT: all our underlays are approved by the building authorities.
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