Yes and no—while TC Ceramic remains an effective insulation solution when applied to the interior of a roof, it functions differently than when applied to an external surface.

How TC Ceramic Works on an Exterior vs. Interior Roof Application

  1. Exterior Roof Application (Best for Solar Heat Reflection)
    • When applied to the external surface of a roof, TC Ceramic acts as a solar heat reflector, reducing the amount of heat absorbed by the building.
    • This results in lower indoor temperatures and reduced air conditioning costs.
    • Recommended thickness: 15 mils (0.4mm) for optimal heat reflection.
  2. Interior Roof Application (Best for Heat Blocking)
    • If applied to the interior of a roof, TC Ceramic will not reflect solar heat, but it will still work as an insulating barrier to reduce heat transfer.
    • Since heat has already entered the roof material, a thicker application (30 to 40 mils or 0.8mm to 1.0mm) is required to effectively block the heat from radiating into the interior space.
    • This helps maintain stable indoor temperatures and reduces the heat load within the building.

Does an Interior Application Still Work?

Yes, TC Ceramic still provides insulation benefits, but it requires a thicker layer to achieve the same level of performance compared to an exterior application. The key difference is that rather than reflecting heat away before it enters the building, the coating works from the inside to prevent stored heat from radiating downward into the occupied space.

Best Use Cases for Interior Roof Applications:

  • Buildings where exterior application isn’t possible (e.g., restrictions on roof modifications).
  • Warehouses, factories, and commercial spaces where excessive internal heat buildup needs to be controlled.
  • Retrofitting older buildings that lack external insulation but require improved energy efficiency.

Final Recommendation:

For maximum efficiency, applying TC Ceramic externally is the preferred method for reducing heat buildup. However, when external application isn’t an option, applying 30-40 mils (0.8mm-1.0mm) on the interior is an effective alternative for blocking heat from radiating inside.

If you’re unsure which application method is best for your specific project, our team can help determine the ideal thickness and placement for maximum thermal performance.