Sikagard® M 338

Water based, rigid epoxy coating for waterproofing and protection of concrete elements

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Sikagard® M 338 is a two component, water borne rigid epoxy coating for waterproofing and protection of concrete elements.

  • Water-based
  • Excellent adhesion to concrete even when damp
  • Does not require an extra primer
  • Once hardened it is impermeable to water and carbon dioxide
  • Good water vapour permeability – low risk of blistering
  • Resistant to water, weather and freezing conditions
  • Good chemical resistance
  • High abrasion resistance
  • Easy to apply by roller, brush, or with airless gun
  • Easy to clean and maintain
Product Data Sheet Show all documents

Overview

Usage

  • For both inside and outside use.
  • For use on horizontal and vertical surfaces.
  • For use on concrete and cementitious mortars.
  • Protection of pipes, channels, tanks, sinks etc.
  • For use on retaining walls, bridge facings and building structures.
  • For early protective coating of fresh precast concrete elements
  • For protection of tunnels.
Contact your local Sika representative regarding any application required not mentioned here.

Advantages

  • Water-based
  • Excellent adhesion to concrete even when damp
  • Does not require an extra primer
  • Once hardened it is impermeable to water and carbon dioxide
  • Good water vapour permeability – low risk of blistering
  • Resistant to water, weather and freezing conditions
  • Good chemical resistance
  • High abrasion resistance
  • Easy to apply by roller, brush, or with airless gun
  • Easy to clean and maintain

Packaging

Sikagard® M 338 is available in 25 kg kits consisting of 20.6 kg Part A + 4.4 kg Part in metal pails.

Colour

Part A: grey viscous liquid.

Part B: colourless liquid.

Product Details

APPROVALS / STANDARDS

Test report EN 12873-2:2005 for compliance with RD 140/2003

Shelf Life

12 months after date of production in unopened original packaging, if stored at below mentioned storage condition.

Storage Conditions

Store Sikagard® M 338 in cool and dry warehouse conditions; protect from freezing. No permanent storage over +30 °C.

Density

Approx. 1.35 kg/l (mixed material)

Shore A Hardness

Approx. 94

(EN ISO 868)

Abrasion Resistance

weight loss H22 wheel

and 1 kg load

1090 mg

Resistance to Impact

Class II: ≥ 10 Nm

(EN ISO 6272-1)

Tensile Adhesion Strength

Adhesion to concrete

> 3.0 N/mm²

Reaction to Fire

Class Bfl-s1

Chemical Resistance

Chemicals

Resistance to severe chemical attack:

Group 1: Gasoline

Group 3: heating oil, Diesel fuel, unused motor and gear oils

Group 5: Mono- & poly alcohols, glycol ethers

Group 10: Mineral acids (non oxidizing) ≤ 20% and inorganic salts in aqueous solution (pH<6)

Group 11: Inorganic bases and their hydrolysing salts in aqueous solution (pH>8)

Group 12: solutions of inorganic non-oxidizing salts with a pH value between 6 and 8

Group 14: Aqueous solutions of organic surfactants

Class II (28d without pressure)

For more information on chemical resistance, please contact our technical service.

Thermal Resistance

-30 °C to +80 °C

Resistance to Weathering

Adhesion strength after freeze-thaw with de-icing salts (50 cycles) and thunder shower (10 cycles)

> 2.5 N/mm² no blisters, scaling or cracking

Behaviour After Artificial Weathering

No defects observed

(EN 1062-11)

Permeability to Water Vapour

SD = 7 m

(EN 1062-3)

Capillary Absorption

0.02 kg/m2·h0.5

Diffusion Resistance to Carbon Dioxide

SD > 750 m

Application

Layer Thickness

Application thickness (wet film)

1st coat (200 g/m²)

150 µm

2nd coat (250 g/m²)

185 µm

Minimum total thickness, 2 coats (dry film)

200 µm

Product Temperature

+10 °C to +30 °C 

Ambient Air Temperature

+10 °C to +30 °C 

Relative Air Humidity

≤ 80 %

Substrate Temperature

+10 °C to +30 °C 

Substrate Moisture Content

Substrate can be damp, but not wet.

Pot Life

At +30 °C

approx. 40 – 60 minutes

At +20 °C

approx. 70 – 90 minutes

At +10 °C

approx. 120 – 150 minutes

Waiting Time / Overcoating

approx. 12 - 18 hours*

Applied Product Ready for Use

Walkable after

approx. 24 hours*

Fully cured after

7 days*

* At 21±2 °C and 60±10% relative humidity. Higher temperatures or lower R.H. will shorten these times, and vice versa.

Consumption

A minimum of two coats is required.

First layer consumption is approx. 0.2 kg/m².

Second and subsequent coats require approx. 0.25 to 0.3 kg/m² each.

These consumptions are theoretical and can vary according to the absorption and roughness of the substrate. It is essential to carry out representative trials on site to evaluate the exact consumption.

SUBSTRATE PREPARATION

All substrates (new and old) must be structurally sound, dry, free of laitance and loose particles and clean of oil, grease, rubber skid marks, paint stains and other adhesion impairing contaminants.

The surface should be prepared by shot blasting, high-pressure water jetting or other suitable mechanical method.

After surface preparation the tensile strength of the substrate should exceed 1.5 N/mm² (check with an approved pull-off tester).

The temperature of the substrate must be at least 3 °C above the current dew point temperature.

Try to keep the temperature uniform during application and hardening.

 

MIXING

Sikagard® M 338 is supplied in two separate components in the correct quantities, ready for mixing.

Pour Part B into Part A, ensuring to completely empty the pack of Part B, and mix with a slow speed drill and paddle (maximum 400 rpm) until a homogeneous mixture is obtained.

Avoid the inclusion of air. Part mixes are strictly forbidden.

APPLICATION

Sikagard® M 338 has to be applied in two coats, if required in three coats. The consumption per coat depends on the roughness of the substrate and the type of application.

Dilute the material with 10% clean tap water for the first coat. Subsequent layers need to be applied undiluted, when the first one is touch dry.

Sikagard® M 338 can be applied using a brush, a short hair roller or an air-less spray gun.

Parameters for spraying:

  • Pressure: approx. 220 bar

  • Flow rate: min. 5 l/min

  • Nozzle size: min: 0.83 mm.

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