The application of SANAT aerogel coating on building walls requires strict procedural discipline, with the core principle following a systematic coating system: primer + intermediate coat + topcoat. The standard application procedure is as follows:
Pre‑Construction Preparation
Several preparatory tasks are critical before starting the work:
- Inspect the Substrate (Wall Surface) – This is the foundation of a successful application. Ensure the wall is solid, flat, clean, and dry.
- Solid: Remove any loose, hollow, or peeling old coatings.
- Flat: Check flatness with a 2‑metre straightedge; the deviation should be less than 2 mm. Fill cracks and holes with mortar and smooth them out.
- Clean: Remove all oil stains, dust, moss, and other contaminants from the wall.
- Dry: The moisture content of the wall must be below 10%, and the pH value should be less than 10.
- Prepare Materials and Tools – Have the following ready:
- Core materials: SNTZ‑100 SANAT aerogel thermal‑insulating intermediate coating, matching alkali‑resistant primer, and SNTZ‑101 SANAT reflective thermal‑insulating topcoat.
- Essential tools: Electric mixer, high‑pressure airless sprayer (or rollers, trowels), wet‑film thickness gauge, etc.
- Check Environmental Conditions – The application environment must meet these requirements:
- Temperature: Between 5 °C and 40 °C.
- Humidity: Relative air humidity should not exceed 85%.
- Weather: Avoid construction during foggy, excessively humid, or rainy periods (both before and after rain).
Four‑Step Application Process
Step 1 – Apply the Primer
- Purpose: Seal the substrate and improve adhesion for subsequent coats.
- Method: Use rolling or spraying; for complex areas (corners, window sills), apply first with a brush, then cover larger surfaces.
- Drying time: At 25 °C, allow at least 6 hours for drying – the surface should be dry to the touch.
Step 2 – Spray or Trowel the SNTZ‑100 SANAT Aerogel Thermal‑Insulating Intermediate Coat (Core Step)
- Purpose: This is the functional layer that provides the thermal insulation performance.
- Method: Spraying or trowelling is recommended. If using a trowel, each pass should not exceed 1 mm in thickness.
- Critical points – Thickness and Intervals:
- Apply in multiple passes – do not attempt to achieve the full thickness in a single coat to ensure quality and performance.
- Standard total dry film thickness: 2–3 mm. The usual practice is to apply two passes, each about 1 mm thick.
- Mandatory waiting time between passes: Allow at least 6 hours between coats. This allows proper solvent evaporation, prevents cracking, and ensures the insulation effect.
- Mixing the coating: Before application, mix the material with an electric mixer for at least 3 minutes until uniform. If dilution is necessary, add no more than 5% water (unless otherwise specified by the manufacturer).
Step 3 – Apply the Reflective Thermal‑Insulating Topcoat on Exterior Walls; for Interior Walls, Apply Putty Leveling Followed by Emulsion Paint or Other Decorative Finishes
- Purpose: Provides a decorative finish and reflects part of the solar heat, acting as a “sunshield”.
- Method: Can be applied by rolling, brushing, or spraying, usually in one to two coats.
Post‑Application Inspection and Maintenance
- Quality inspection: Check each coat after it has dried. After completion, use a non‑destructive dry‑film thickness gauge to verify that the total thickness meets the design requirements.
- Maintenance: It is recommended to carry out an annual inspection after project delivery. Surface dirt can be rinsed with clean water, and localized damage can be repaired by patching.
Three Key Pitfalls to Avoid
- Ensure thorough mixing before use – SNTZ‑100 SANAT aerogel coating may experience separation during long‑distance transport and storage. Stir it thoroughly before opening and using to avoid compromising its thermal insulation performance.
- Thickness is non‑negotiable – A dry film thickness of at least 2 mm is the minimum to achieve effective insulation. Use a thickness gauge during application to check compliance.
- Hire experienced contractors – Aerogel coatings require specific spray equipment and operating techniques. Choosing a team with relevant project experience is crucial to ensure that final thermal performance targets are met.
Final Summary
In summary, the application of SANAT aerogel coating on building walls is not overly complicated, but success depends on rigorous substrate preparation, thin‑layer multi‑pass application, and strict adherence to drying intervals. When these guidelines are followed, the coating delivers outstanding thermal insulation performance.
