Dekguard E2000: Elastomeric Protective Coating for Concrete and Masonry

Product Overview

Dekguard E2000 is an elastomeric, pigmented acrylic protective and decorative coating system designed specifically for protecting atmospherically exposed reinforced concrete structures from environmental attack. The system comprises two complementary components: a penetrating silane-siloxane primer (Nitoprime DG) and a single-component elastomeric pigmented coating, both water-based and ready for immediate site use.

Primary Uses and Applications

Dekguard E2000 is engineered to protect atmospherically exposed, non-trafficked reinforced concrete structures from attack by:

• Acid gases in the atmosphere
• Chloride ions from salt-laden environments
• Oxygen penetration
• Water ingress and moisture penetration

The coating is particularly suitable for use on all types of structures, including those in coastal environments where chloride ion exposure is a significant concern. It is equally effective for protecting new and existing structures, and serves as a component of Fosroc's Renderoc system of concrete reinstatement. Dekguard E2000 can also be applied to other cementitious substrates and masonry in addition to reinforced concrete.

Key Advantages

Dekguard E2000 offers several distinctive performance characteristics:

• Substrate cracking accommodation: The coating can accommodate substrate cracking, providing flexibility to handle structural movement
• Elastomeric properties: True elastomeric coating with excellent elongation and recovery properties
• Multi-functional barrier: Provides an excellent barrier to carbon dioxide, chloride ions, oxygen, and water
• Dirt resistance: Special acrylic polymer formulation minimizes dirt retention on the coating surface
• Vapor transmission: Allows water vapor to escape from the protected structure while blocking liquid water
• UV resistance: UV-resistant with high resistance to the effects of long-term weathering
• Water-based formulation: Environmentally friendly and easy to handle

Technical Specifications and Properties

The following properties are typical values obtained for the Dekguard E2000 system applied at the minimum recommended application rate:

Physical Properties:

• Volume solids: Approximately 50%
• Elongation at Break: Greater than 300% (ASTM D412)
• Fire testing - Spread of flame: Class 1 (BS 476, Part 7: 1987)

Diffusion Resistance and Protection Characteristics:

• Carbon dioxide diffusion resistance:

  • Equivalent thickness of air (R): Greater than 96 metres
  • Equivalent thickness of 30 MPa concrete cover: Greater than 240 mm
  • CO₂ Diffusion Coefficient: 3.7 × 10⁻⁰⁷ cm²/sec

• Chloride ion diffusion coefficient: 2.3 × 10⁻¹⁴ m²/sec at 147 days (AS/NZS 4548.5-1999)

• Water vapour transmission resistance (AS/NZS 4548.5-1999):

  • Vapour Transmission Rate: 55.7 g/m²/24 hour
  • Equivalent thickness of Air (Sd): Less than 1 m
  • Vapour Diffusion Coefficient: 1.1 × 10⁻⁰⁴ cm²/sec

• Water Transmission Resistance: 14 g/24h/m²/KPa (AS/NZS 4548.5-1999)

System Composition

The Dekguard E2000 system comprises:

1. Nitoprime DG (Primer Component)

• Film-forming, stabilising primer supplied as a clear liquid
• Based on acrylic resin and silane-siloxane dissolved in penetrating organic carrier
• Reactive formulation capable of producing a chemically-bound hydrophobic barrier
• Inhibits the passage of water and water-borne contaminants
• Consolidates and stabilises porous substrates with a thin surface film

2. Dekguard E2000 (Elastomeric Coating)

• Single-component, water-based protective coating
• Based on special acrylic polymer
• Provides excellent elongation and recovery
• Exhibits low dirt pick-up characteristics
• Demonstrates resistance to aggressive elements, UV light, and rain

Design Criteria and Application Requirements

The coating should generally be applied in two coats to achieve a total dry film thickness of not less than 200 microns in order to accommodate substrate cracking. However, it is possible to achieve the total dry film thickness in one coat, depending on the substrate type and finish required. Trials are recommended prior to full application to ensure the finish meets client requirements.

Application Parameters:

Parameter	Nitoprime DG	Dekguard E2000 (One Coat)	Dekguard E2000 (Two Coats)
Number of coats	Flood coat	1	2
Theoretical application rate per coat	0.4 litres/m²	0.4 L/m²	0.2 L/m²
Theoretical wet film thickness	N/A	400 microns per coat	200 microns per coat
Overcoating time	2 hours @ 20°C	N/A	8 hours @ 20°C

Surface Preparation Requirements

All surfaces must be thoroughly prepared before application:

• Surfaces must be dry and free from contamination including:
  • Oil and grease
  • Loose particles
  • Decayed matter
  • Moss and algal growth
  • Laitance
  • All traces of mould release oils and curing compounds

Recommended preparation method: Light grit-blasting of the surface is the best technique to achieve proper substrate preparation. Where moss, algae, or similar growths have occurred, treatment with a proprietary biocide should be carried out after the grit-blasting process.

Surface defects: Surfaces containing blowholes or similar areas of pitting should first be filled using Renderoc FC or Renderoc ST 06 (cementitious fairing coats). These fairing coats should be allowed to cure for approximately 48 hours, depending on ambient conditions, before application of Dekguard E2000.

Existing coatings: Where application over existing sound coatings or paints is required, trials should be conducted to ensure compatibility and retention of bond between the underlying coating and the substrate.

Application Instructions

Primer Application (Nitoprime DG)

Nitoprime DG should be applied first as a flood coat. It should be applied in one or more coats until the recommended application rate of 0.4 litre per square metre has been achieved. This is best accomplished using portable spray equipment of the knapsack-type. A uniform surface appearance (sheen) should be achieved; if any matt porous patches remain, a further application of primer should be made.

The primer must be allowed to dry for a minimum of two hours at 20°C before overcoating with Dekguard E2000. The primer surface must be properly dry before application of the topcoat.

Topcoat Application (Dekguard E2000)

Dekguard E2000 may be applied by suitable brushes, rollers, or spray equipment. All primed substrates should be treated with one or two coats of Dekguard E2000 as specified. It is important that no gaps or 'raw edges' appear in the finished coating, with special care taken at external corners and similar exposed protrusions.

Single Coat Application: When being applied to well-prepared surfaces without blow holes, it is possible to spray apply Dekguard E2000 in a single coat to achieve the 400 micron wet film thickness (200 micron dry film thickness). Suitable equipment includes Graco 795 or Graco 1095 airless spray running at 3000 psi with 19 or 21 thou spray tips.

Environmental and Temperature Constraints

• Minimum substrate temperature: Application should not commence if the substrate temperature is below 5°C
• Frost protection: Dekguard E2000 should not be applied where there is a likelihood of exposure to frost within 48 hours of application
• Humidity limitation: Should not be applied when prevailing relative humidity exceeds 90%
• Rain protection: Product should not be applied where rain is likely within:
  • 2 hours at 20°C, or
  • 20 hours at 5°C (up to 80% RH)
• Windy conditions: Should not be applied in windy conditions where early-age dust adhesion may occur

Product Limitations

The Dekguard E2000 system has several important limitations:

• Formulation: Formulated specifically for clean, sound concrete or masonry substrates
• Ponded water exposure: Should not be considered for areas subjected to exposure to ponded water; Dekguard S should be used where occasional ponded water is anticipated
• Traffic: Dekguard coatings are not designed nor suitable for use on trafficable surfaces
• Coating compatibility: When applied over existing coatings or paints, the performance characteristics of Dekguard E2000 may be impaired and its fire rating may be invalidated

Coverage and Supply Information

Coverage rates:

• Dekguard E2000: 2.5 m² per litre (total)
• Nitoprime DG: 2.5 m² per litre (total)

Note: Coverage figures given are theoretical. Due to wastage factors and the variety and nature of possible substrates, practical coverage figures will be reduced.

Supply formats (made to order, subject to minimum order quantities):

• Dekguard E2000 White 15L: FC860625-15L
• Dekguard E2000 Special Colour 15L: FC860626-15L
• Dekguard E2000 In Can Tint 15L: FC860628-15L
• Nitoprime DG 20 litres: FC862600-20L
• Fosroc Solvent 10 4 litre: FC600800-4L
• Fosroc Solvent 10 20 litre: FC600800-20L

Storage and Handling

Store Dekguard E2000 in cool, dry conditions. The product should be protected from frost during storage to maintain its properties.

Equipment Cleaning

Dekguard E2000 should be removed from tools and equipment with clean water immediately after use. Nitoprime DG should be removed from tools and equipment using Fosroc Solvent 10 immediately after use.

Safety Information

A Safety Data Sheet (SDS) is available from the Fosroc website and must be read carefully prior to use, as application or performance data may change from time to time. In emergencies, contact a Poisons Information Centre or doctor for advice.

References

• [1] Fosroc_Dekguard_E2000_TDS.pdf
• [2] Fosroc_Nitoprime_DG_TDS.pdf
• [3] Fosroc_Dekguard_Primer_TDS.pdf