Surface Treatment

Water Repellant Sealer

Monneli Idrosil A

Water Repellant Penetrating Water Based Sealer

IDROSIL A is used as a surface treatment designed to protect:
Masonry surfaces
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Technical Information
Product Description

IDROSIL A is a single component siliconate solution designed to impart water repellency and reduce water absorption to a wide variety of surfaces.

IDROSIL A penetrates deeply into new or existing concrete or masonry for maximum protection against different substances, water penetration, chloride ion attack and freeze-thaw cycles.

The water based sealer is characterized by an excellent ability to penetrate all porous materials used in masonry surfaces. It doesn’t create a film and therefore it allows the substrates to breath.

  • Excellent water repellant characteristics
  • Reduces water absorption into the substrate, thus reducing spalling due to freeze-thaw and efflorescence, thereby increasing the life of the substrate.
  • Long lasting protection
  • Transparent and non-staining/non-yellowing
  • Eco-friendly. Low Volatile Organic Content
  • Breathable. Allows interior moisture to escape without damaging the sealer
  • Non-flammable
Compiliance Standard
  • ASTM C 1202
Packaging, Coverage / Consumption


IDROSIL A is packed in 20 liters and 210 liters drums.



6-8m²/ liter depending on the porosity of the substrate

Shelf Life & Storage


Keep in original well closed drum, in dry and sheltered place, at the temperature between +5ºC and +35ºC. Shelf life is 6 months from date of manufacturing when stored properly.

Technical Properties



Transparent liquid

Density at 25°C

 1.03 kg/L


< 4 g/L

Drying time at 25°C

6 - 8 hours

pH at 25°C

8.0 - 9.0

Temperature of application

from +5°C to +35°C

Waiting time before top painting

Minimum 24 hours

Rapid chloride permeability

Very low

Harmfulness EEC 88/379

Harmful for contact

All values are subject to 5-10 % tolerance

Application Information
Instructions for use

Surface Preparation

All surfaces should be clean, sound and uncontaminated. This preparation should leave an exposed concrete, free from dust, loose particles, deleterious matter, oil, grease, chemical films and other contaminants.


IDROSIL A is a single component solution, applied at full strength.

Mix the material thoroughly before & during application. IDROSIL A should be applied with a brush, roller or low pressure non-atomizing spray uniformly onto the surface at a rate of 4-5 m2/ liter.

For vertical surfaces, flood the surface by applying from the bottom up applied to saturation with a controlled material rundown to ensure maximum penetration on the surface.

Extremely porous substrate may require two coats. Apply the second coat as soon as the initial surface drying of the first coat has been visible which around 2-4 hours is at ambient temperature. Cooler temperature or higher relative humidity may extend drying time.

Surfaces with salty efflorescence must be cleaned mechanically or washed with acid cleaner and subsequently rinsed with water. Wait for the surface to dry, before proceeding with the application of IDROSIL A.

All cement supports must be allowed to cure for at least 21 days before being impregnated with the product.


After application of IDROSIL A, allow the treated surface to dry for at least 24 hours to develop maximum water repellency.


Equipment and tools used should be cleaned promptly with water.


  • Do not apply if rain, dew or water exposure is expected with 24 hours of application. Avoid application in direct sunlight and during high winds
  • Do not use onto the gypsum supports
  • Do not apply in areas where negative hydrostatic pressure is possible
Additional Information
Health & Safety

Direct contact with the product may result in irritation of the skin and eyes. Product vapors may also cause irritation.

Wear gloves and masks during application. Remove any contaminated clothing and wash skin thoroughly with soap and water. Remove ignition sources prior to use.

In case of accidental eye contact, wash with plenty amount of water and seek immediate medical attention.

Important note

The information in this Technical Data Sheet is based on Colmef Monneli’s experience. Colmef Monneli does not accept any liability arising from the use of its products as it has no direct or continuous control over where or how its products are applied. All Colmef Monneli’s Data Sheets are updates on regular basis. It is the user’s responsibility to obtain the latest version.

additional materials
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Technical Properties Sheet
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