Rubberizeit Support

DUR-RUBBER FOR METAL

Overview

Applying Dura-Rubber over metal provides waterproofing and corrosion protection. By following the correct procedures, including applying fabric and product per the application chart on seams, penetrations, cracks, and wall intersections, you can extend the life of your metal roof by 5 to 10 years, depending on its condition.

Additionally, Dura-Rubber is effective for protecting mechanical equipment from rust and UV damage. See the related sections for HVAC Equipment Coatings and Swamp Coolers for further details.

Step-by-Step Instructions for Applying Dura-Rubber for Metal Applications 

Step 1: Prepare the Surface

• Clean Thoroughly: Remove all dirt, dust, grease, oil, loose material, mold, mildew, or anything that could affect adhesion. Use a 2,500 PSI pressure washer with detergent if needed (avoid over-washing to prevent driving water into concrete). For mildew, apply a 5% chlorine bleach solution, rinse well, and let dry fully.
• Special Prep for Fiberglass, Epoxy Paints, Glossy Surfaces and plastics:  surface should be scuff-sand with medium-grit sandpaper (e.g., 120-150 grit) to roughen the surface, then wipe with acetone to remove dust and oils. Let it dry fully before proceeding. These materials should be primed. 
• Ensure Dryness: The surface (e.g., concrete) must be completely dry (less than 7% moisture). Use a moisture meter to test multiple spots, especially low areas, as concrete retains moisture deep down. If damp, use fans to dry it out.
• Check the Dew Point condensation will form on metal  

.

Step 2: Mix the Product

Step 3: Test Adhesion

• After confirming dryness, perform an adhesion test: (Required for all applications)
  • Select a small, inconspicuous area (e.g., 1 sq ft) on your surface.
  • Clean and dry it as outlined above.
  • Apply a coat of primer (required for underwater applications; optional otherwise) and let it dry for 48 hours.
  • Check adhesion: Use a utility knife to make a small X-cut, press adhesive tape over it, and pull sharply. If the coating peels off easily, it’s not bonding well. Adjust prep (e.g., more cleaning or drying) and retest if needed.

Step 4: Inspect and Repair

Step 5: Apply Primer (typically 250 sq ft/gallon). 

Step 6: Apply Dura-Rubber Coats

• Application Method: Apply by brush, with a 3/4" nap roller, or using an airless sprayer with a .025 tip.
• Target Thickness: Aim for 20 mils dry (40 sq ft/gallon). Apply 3 coats at 10-12 mils wet each (since it’s 55% solids, this yields 18-22 mils dry). Don’t exceed 12 mils per coat to avoid cracking as water evaporates.
  • Rule of Thumb for 10-12 Mils Wet: Spread 1 gallon evenly over about 120-140 sq ft per coat (so 40 sq ft total across all 3 coats). Visually, it should feel like the thickness of a standard business card (about 10-12 mils)—smooth and even, fully covering the surface without pooling. For precision, use a wet mil gauge from a hardware store.
• Temperature Check: Apply when the surface temperature (of the material being coated) is between 45°F and rising and 80°F. Use a surface thermometer to confirm—below 45°F, it won’t cure properly; above 80°F, it may dry too fast and crack.
• Drying Between Coats: Wait at least 3-4 hours between coats for “deep drying” (all water must evaporate, or bubbles will form). Adjust based on temperature and humidity (40-50% RH is optimal; avoid applying above 70% RH). There’s no maximum recoat time—apply the next coat any time after the previous one is fully dry, even days later, as long as the surface remains clean and dry. Apply all 3 coats within 24 hours if aiming for a continuous process.
• Tips: Start early in the day when temps are rising, but beware of dew if applicable (e.g., for outdoor pools in humid climates—wait until it evaporates, and the surface is dry). Ensure all edges/terminations are above the water line and dry.

Step 7: Cure the Coating

• Curing Time: After the final coat, let it cure for 7-10 days (outdoor pools) or 14 days (indoor pools) before filling with water. Use fans for ventilation.
• Weather Impact: Add 1 extra day for each day of rain or high humidity during curing. At 70°F and 50% RH, 7 days is the minimum for outdoor pools.
• Why It Matters: The coating is dry to the touch in hours but needs curing to form a solid, waterproof membrane. Filling too early causes gas bubbles.

Step 8: Final Checks

• Avoid Chemicals/Water: Don’t expose the coating to chemicals or continuous water until fully cured.
• Control Sample (Underwater Use): Coat a concrete brick alongside your pool, let it cure, and keep it as a reference.

Key Notes

• Tools Needed: Moisture meter, pressure washer, 3/4" nap roller, brush, airless sprayer (.025 tip), reinforcement fabric, fans, utility knife, adhesive tape (for adhesion test), surface thermometer (for temp check), plastic sheet and duct tape (for moisture test if no meter), wet mil gauge (optional for thickness), medium-grit sandpaper (for glossy surfaces).
• Conditions: Best at 40-50% RH and surface temps of 45°F (rising) to 80°F. Avoid 70%+ RH or temps outside this range to prevent curing or cracking issues.
• Thinning (If needed): If Dura-Rubber needs to be thinned, it can be mixed with up to 10% by volume of propylene glycol.
• Support: Contact the company if unsure about your specific surface or conditions.

Disclaimer

These instructions are based on typical applications and may vary depending on conditions and surfaces you apply to. Please contact support for additional application help. Rubberizeit Dura-Rubber pool coating is a water- and airtight product that has been used for pools and ponds for over 10 years. We have no control over the application or conditions that could affect results. Virtually all problems in applications stem from the substrate not being dry or not being cleaned properly—following these instructions completely will help eliminate issues. For underwater applications, we require a control sample: coat a concrete brick with Dura-Rubber as you coat the substrate, let it dry and cure, and keep it as a reference.

Application Instructions for Metal PDF