Stoneware Studios manufacture, supply and promote an extensive range of quality materials and services for the repair of Historic Buildings.

Diathonite Thermactive.037

Insulating the building and maintaining the breathability of the wall/ceiling

The insulating action of air

Diathonite Thermactive.037 is formulated with highly porous materials. Air fills the empty gaps in the structure enhancing the thermal insulation. We make the most of the innate properties of nature.

Thermal Conductivity

λ = 0,037 W/mK

The extremely low lambda implies insulation from both cold and heat, therefore it solves problems related to thermal bridges and guarantees a healthy environment and high living comfort.


Thermal Diffusivity

α = 0,1 x 10⁻⁶ m²/s
The low diffusivity value (α) indicates a high degree of insulation from heat and therefore greater comfort and savings for summer cooling.


μ = 3

Thanks to the high value of permeability (μ), the humidity of the indoors is perfectly balanced, thus avoiding the formation of moulds and condensation.


Fire resistant


Classified in class A1 according to UNI EN ISO 13501-1. No flame generation and no smoke emission.


ρ = 250 ± 15% kg/m³

Its macroporous structure and the use of natural components allows the product to be lighter than a traditional plaster. Its performance in terms of insulation and absorption of excess moisture is guaranteed.



The macroporous structure is characterized by high air molecules content that guarantee excellent performance in terms of insulation and absorption of excess moisture.

Compressive strength

2,8 N/mm²

High compressive strength gives the wall greater consistency and stability.

Protects from cold in winter and overheating summer

Not only an excellent insulation system

  • The best thermal conductivity available in a plaster
  • Breathable and Capillary active
  • Easy thermal bridge solution
  • Euroclass A1 fire resistance, does not burn or smoke so improves fire safety of buildings.
  • Up to 10 times more elastic than traditional plasters reducing the risk of cracks
  • Antibacterial Properties
  • Creates a sympathetic restoration and insulation which maintains the unique characteristic of existing walls allowing them to breathe and balance room humidity
  • 50mm of Thermactive improves the thermal performance of a wall by approximately 4 times keeping walls warm in the winter and cool in summer